FT232BL/BQ Datasheet by FTDI, Future Technology Devices International Ltd

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Copyright © 2011 Future Technology Devices International Limited 1
Document No.: FT_000329
FT232BL/BQ USB UART IC Datasheet Version 2.2
Clearance No.: FTDI# 171
Future Technology
Devices International Ltd.
FT232BL/BQ USB UART IC
The FT232B is a USB to serial UART
interface with the following advanced
features:
Single Chip USB to Asynchronous Serial
Data Transfer
Full Handshaking & Modem Interface
Signals
UART I/F Supports 7 / 8 Bit Data, 1 / 2
Stop Bits and Odd/Even/Mark/Space/No
Parity
Data rate 300 => 3M Baud (TTL)
Data rate 300 => 1M Baud (RS232)
Data rate 300 => 3M Baud
(RS422/RS485)
384 Byte Receive Buffer / 128 Byte
Transmit Buffer for high data throughput
Adjustable RX buffer timeout
Fully Assisted Hardware or X-On / X-Off
Handshaking In-built support for event
characters and line break condition
Auto Transmit Buffer control for RS485
Support for USB Suspend / Resume
through SLEEP# and RI# pins
4.35V to 5.25V single supply operation
Support for high power USB Bus powered
devices through PWREN# pin
Integrated level converter on UART and
control signals for interfacing to 5V and
3.3V logic
Integrated 3.3V regulator for USB IO
Integrated Power-On-Reset circuit
Integrated 6MHz 48Mhz clock multiplier
PLL
UHCI / OHCI / EHCI host controller
compatible
USB 1.1 and USB 2.0 compatible
USB VID, PID, Serial Number and Product
Description strings in external EEPROM
EEPROM programmable on-board via USB
Available as a compact lead free RoHS
compliant 32-LD LQFP package (FT232BL) or
32-LD QFN package (FT232BQ).
Neither the whole nor any part of the information contained in, or the product described in this manual, may be adapted or reproduced
in any material or electronic form without the prior written consent of the copyright holder. This product and its documentation are
supplied on an as-is basis and no warranty as to their suitability for any particular purpose is either made or implied. Future Technology
Devices International Ltd will not accept any claim for damages howsoever arising as a result of use or failure of this product. Your
statutory rights are not affected. This product or any variant of it is not intended for use in any medical appliance, device or system in
which the failure of the product might reasonably be expected to result in personal injury. This document provides preliminary
information that may be subject to change without notice. No freedom to use patents or other intellectual property rights is implied by
the publication of this document. Future Technology Devices International Ltd, Unit 1, 2 Seaward Place, Centurion Business Park,
Glasgow G41 1HH United Kingdom. Scotland Registered Company Number: SC136640
Linux 2‘4 and greater http: www.ftd \chip.com Documents InstaIIGuides. htm
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FT232BL/BQ USB UART IC Datasheet Version 2.2
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1 Typical Applications
USB to RS232/RS422/RS485 Converters
Upgrading Legacy Peripherals to USB
Cellular and Cordless Phone USB data transfer
cables and interfaces
Interfacing MCU/PLD/FPGA based designs to
USB
USB Audio and Low Bandwidth Video data
transfer
PDA to USB data transfer
USB Industrial Control
USB MP3 Player Interface
Set Top Box PC - USB interface
USB Hardware Modems
USB Wireless Modems
USB Bar Code Readers
USB Smart Card Readers
USB Instrumentation
1.1 Driver Support
Royalty free VIRTUAL COM PORT
(VCP) DRIVERS for...
Windows 98, 98SE, ME, 2000, Server 2003, XP
and Server 2008
Windows 7 32, 64-bit
Windows XP and XP 64-bit
Windows Vista and Vista 64-bit
Windows XP Embedded
Windows CE 4.2, 5.0 and 6.0
Mac OS 8/9, OS-X
Linux 2.4 and greater
Royalty free D2XX Direct Drivers
(USB Drivers + DLL S/W Interface)
Windows 98, 98SE, ME, 2000, Server 2003, XP
and Server 2008
Windows 7 32, 64-bit
Windows XP and XP 64-bit
Windows Vista and Vista 64-bit
Windows XP Embedded
Windows CE 4.2, 5.0 and 6.0
Linux 2.4 and greater
The drivers listed above are all available to download for free from FTDI website (www.ftdichip.com).
Various 3rd party drivers are also available for other operating systems - see FTDI website
(www.ftdichip.com) for details.
For driver installation, please refer to http://www.ftdichip.com/Documents/InstallGuides.htm
1.2 Part Numbers
Table 1.1 Part Numbers
Note: Packing codes for xxxx is:
- Reel: Taped and Reel, (LQFP is 1,000pcs per reel, QFN is 2,500pcs per reel).
- Tray: Tray packing, 250pcs per tray (LQFP only)
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2 FT232B Block Diagram
Figure 2.1 FT232B Block Diagram
For a description of each function please refer to Section 4.
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Table of Contents
1 Typical Applications ...................................................................... 2
1.1 Driver Support .................................................................................... 2
1.2 Part Numbers...................................................................................... 2
2 FT232B Block Diagram ................................................................. 3
3 Device Pin Out and Signal Description .......................................... 6
3.1 32 Pin LQFP Package .......................................................................... 6
3.2 32 Pin QFN Package ............................................................................ 7
3.3 LQFP and QFN Package Pin Out Description ........................................ 8
4 Function Description................................................................... 10
4.1 Key Features and Enhancements from FT8U232AM .......................... 10
4.2 Functional Block Descriptions ........................................................... 12
5 Devices Characteristics and Ratings ........................................... 14
5.1 Absolute Maximum Ratings............................................................... 14
5.2 DC Characteristics............................................................................. 15
6 USB Power Configurations .......................................................... 17
6.1 USB Bus Powered Configuration ...................................................... 17
6.2 Self Powered Configuration .............................................................. 18
6.3 Interfacing to 3.3V Logic .................................................................. 19
6.3.1 Bus Powered Circuit with 3.3V logic drive / supply voltage .............................................. 19
6.3.2 Self Powered Circuit with 3.3V logic drive / supply ......................................................... 20
6.4 Bus Powered Circuit (<=100mA) with Power Control ....................... 21
7 Device Configuration Examples .................................................. 22
7.1 Oscillator Configurations .................................................................. 22
7.2 EEPROM Configuration ...................................................................... 23
8 UART Interface Configurations ................................................... 24
8.1 USB <=> RS232 Converter Configuration ......................................... 24
8.2 USB <=> RS422 Converter Configuration ......................................... 25
8.3 USB <=> RS485 Converter Configuration ......................................... 26
9 LED Interface Configuration ....................................................... 27
10 Package Parameters ................................................................... 28
10.1 LQFP Package Dimension ............................................................... 28
10.2 QFN Package Dimension ................................................................ 29
11 Contact Information ................................................................... 30
Appendix A References ........................................................................... 31
Appendix B List of Figures and Tables .................................................... 32
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Appendix C Revision History ................................................................... 33
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3 Device Pin Out and Signal Description
3.1 32 Pin LQFP Package
Figure 3.1 QFN-32 Package Pin Out and schematic symbol
The part number FT232BM version is also a LQFP-32 package. Please note that this datasheet is not for
the FT232BM. Refer to FTDI website for the FT232BM datasheet.
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3.2 32 Pin QFN Package
Figure 3.2 QFN-32 Package Pin Out and schematic symbol
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3.3 LQFP and QFN Package Pin Out Description
Pin No.
Name
Type
Description
7
USBDP
I/O
USB Data Signal Plus ( Requires 1.5k pull-up to 3V3OUT or RSTOUT# )
8
USBDM
I/O
USB Data Signal Minus
Table 3.1 USB Interface Group
Pin No.
Name
Type
Description
13
VCCIO
PWR
+3.0 volt to +5.25 volt VCC to the UART interface pins 10...12, 14...16 and
18...25. When interfacing with 3.3V external logic in a bus powered design connect
VCCIO to a 3.3V supply generated from the USB bus. When interfacing with 3.3V
external logic in a self powered design connect VCCIO to the 3.3V supply of the
external logic. Otherwise connect to VCC to drive out at 5V CMOS level.
9,17
GND
PWR
Device ground supply pins
6
3V3OUT
Output
3.3 volt Output from the integrated LDO regulator This pin should be decoupled to
GND using a 33nF ceramic capacitor in close proximity to the device pin. Its prime
purpose is to provide the internal 3.3V supply to the USB transceiver cell and the
RSTOUT# pin. A small amount of current (<= 5mA) can be drawn from this pin to
power external 3.3v logic if required.
3,26
VCC
PWR
+4.35 volt to +5.25 volt VCC to the device core, LDO and non-UART interface pins
30
AVCC
PWR
Device analogue power supply for internal x8 clock multiplier
29
AGND
PWR
Device analogue ground supply for internal x8 clock multiplier
Table 3.2 Power and Ground Group
Pin No.
Name
Type
Description
4
RESET#
Input
Active low reset pin. This can be used by an external device to reset the FT232B.
If not required can be left unconnected, or pulled up to VCC.
5
RSTOUT#
Output
Output of the internal Reset Generator. Stays high impedance for ~ 5ms after
VCC > 3.5V and the internal clock starts up, and then clamps its output to the
3.3v output of the internal regulator. Taking RESET# low will also force RSTOUT#
to drive low. RSTOUT# is NOT affected by a USB Bus Reset
12
TXLED#
O.C
LED Drive Pulses Low when Transmitting Data via USB
11
RXLED#
O.C
LED Drive Pulses Low when Receiving Data via USB
27
XTIN
Input
Input to 6MHz Crystal Oscillator Cell. This pin can also be driven by an external
6MHz clock if required. Note: Switching threshold of this pin is VCC/2, so if driving
from an external source, the source must be driving at 5V CMOS level or AC-
coupled to centre around VCC/2.
28
XTOUT
Output
Output from 6MHz Crystal Oscillator Cell. XTOUT stops oscillating during USB
suspend, so take care if using this signal to clock external logic.
31
TEST
Input
Puts the device into IC test mode. Must be tied to GND for normal operation,
otherwise the device will appear to fail.
Table 3.3 Miscellaneous Signal Group
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Pin No.
Name
Type
Description
25
TXD
Output
Transmit Asynchronous Data Output.
24
RXD
Input
Receiving Asynchronous Data Input
23
RTS#
Output
Request to Send Control Output / Handshake Signal.
22
CTS#
Input
Data Terminal Ready Control Output / Handshake Signal.
21
DTR#
Output
Clear To Send Control Input / Handshake Signal.
20
DSR#
Input
Data Set Ready Control Input / Handshake Signal.
19
DCD#
Input
Data Carrier Detect Control Input.
18
RI#
Input
Ring Indicator Control Input. When remote wake up is enabled in the internal
EEPROM taking RI# low (20ms active low pulse) can be used to resume the PC
USB host controller from suspend.
16
TXDEN
Output
Enable Transmit Data for RS485.
Table 3.4 UART Interface Group
Pin No.
Name
Type
Description
32
EECS
I/O
EEPROM Chip Select. For 48MHz operation pull EECS to GND using a 10K resistor.
For 6MHz operation no resistor is required. Tri-State during device reset. **Note 1
1
EESK
Output
Clock signal to EEPROM. Tri-State during device reset, else drives out. Adding a
10K pull down resistor onto EESK will cause the FT232B to use USB Product ID
6004 (hex) instead of 6001 (hex). All of the other USB device descriptors are
unchanged.**Note 1
2
EEDATA
I/O
EEPROM Data I/O Connect directly to Data-In of the EEPROM and to Data-Out of
the EEPROM via a 2.2K resistor. Also, pull Data-Out of the EEPROM to VCC via a
10K resistor for correct operation. Tri-State during device reset. **Note 1
Table 3.5 EEPROM Interface Group
Pin No.
Name
Type
Description
10
SLEEP#
Output
Goes Low during USB Suspend Mode. Typically used to power-down an external
TTL to RS232 level converter IC in USB RS232 converter designs
15
PWREN#
Output
Goes Low after the device is configured via USB, then high during USB suspend.
Can be used to control power to external logic using a P-Channel Logic Level
MOSFET switch. Enable the Interface Pull-Down Option in EEPROM when using the
PWREN# pin in this way.
14
PWRCTL
Input
Bus Powered Tie Low / Self Powered Tie High (to VCCIO)
Table 3.6 Power Control Group
**Note 1 During device reset, these pins are tri-state but pulled up to VCC via internal 200K resistors.
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4 Function Description
The FT232B is a lead free version of the 2nd generation of FTDI’s USB to serial UART interface device
which simplifies USB to serial designs. This device not only adds extra functionality to its FT8U232AM
predecessor and reduces external component count, but also maintains a high degree of pin compatibility
with the original, making it easy to upgrade or cost reduce existing designs as well as increasing the
potential for using the device in new application areas. This section summarises the enhancements of
the 2nd generation device compared to its FT8U232AM predecessor.
4.1 Key Features and Enhancements from FT8U232AM
Integrated Power-On-Reset (POR) Circuit. The device now incorporates an internal POR
function. The existing RESET# pin is maintained in order to allow external logic to reset the
device where required, however for many applications this pin can now simply be hard wired to
VCC. In addition, a new reset output pin (RSTOUT#) is provided in order to allow the new POR
circuit to provide a stable reset to external MCU and other devices. RSTOUT# was the TEST pin
on the previous generation of devices.
Integrated RCCLK Circuit. In the previous devices, an external RC circuit was required to ensure
that the oscillator and clock multiplier PLL frequency was stable prior to enabling the clock
internal to the device. This circuit is now embedded on-chip the pin assigned to this function
is now designated as the TEST pin and should be tied to GND for normal operation
Integrated Level Converter on UART interface and control signals. The previous FTDI devices drive
the UART and control signals at 5V CMOS logic levels. The FT232B has a separate VCCIO pin allowing the
device to directly interface to 3.3V and other logic families without the need for external level converter
Ics
Improved Power Management control for USB Bus Powered, high current devices. The previous
devices had a USBEN pin, which became active when the device was enumerated by USB. To provide
power control, this signal had to be externally gated with SLEEP# and RESET#.
This gating is now done on-chip USBEN has now been replaced with the new PWREN# signal which can
be used to directly drive a transistor or P-Channel MOSFET in applications where power switching of
external circuitry is required. A new EEPROM based option makes the device pull gently down its UART
interface lines when the power is shut off (PWREN# is High). In this mode, any residual voltage on
external circuitry is bled to GND when power is removed thus ensuring that external circuitry controlled
by PWREN# resets reliably when power is restored
Lower Suspend Current. Integration of RCCLK within the device and internal design improvements
reduce the suspend current of the FT232B to under 200uA (excluding the 1.5k pull-up on USBDP) in USB
suspend mode. This allows greater margin for peripherals to meet the USB Suspend current limit of
500uA.
Programmable Receive Buffer Timeout. In the previous device, the receive buffer timeout flushed
remaining data from the receive buffer at a fixed 16ms timeout. This timeout is now programmable over
USB in 1ms increments from 1ms to 255ms, thus allowing the device to be better 10ptimized for
protocols requiring faster response times from short data packets.
TXDEN Timing fix. TXDEN timing has now been fixed to remove the external delay that was previously
required for RS485 applications at high baud rates. TXDEN now works correctly during a transmit send-
break condition.
Relaxed VCC Decoupling. The FT232B devices now incorporate a level of on-chip VCC decoupling.
Though this does not eliminate the need for external decoupling capacitors, it significantly improves the
ease of PCB design requirements to meet FCC, CE and other EMI related specifications.
Improved PreScaler Granularity. The previous version of the Prescaler supported division by (n + 0),
(n+0.125), (n + 0.25) and (n + 0.5) where n is an integer between 2 and 16,384 (214). To this FTDI
have added (n + 0.375), (n + 0.625), (n + 0.75) and (n+ 0.875) which can be used to improve the
accuracy of some baud rates and generate new baud rates which were previously impossible (especially
with higher baud rates).
Bit Bang Mode. The 2nd generation device has a new option referred to as “Bit Bang” mode. In Bit Bang
mode, the eight UART interface control lines can be switched between UART interface mode and an 8-bit
Parallel IO port. Data packets can be sent to the device and they will be sequentially sent to the interface
at a rate controlled by the prescaler setting. As well as allowing the device to be used stand-alone as a
general purpose IO controller for example controlling lights, relays and switches, some other interesting
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possibilities exist. For instance, it may be possible to connect the device to an SRAM configurable FPGA as
supplied by vendors such as Altera and Xilinx. The FPGA device would normally be un-configured (i.e.
have no defined function) at power-up. Application software on the PC could use Bit Bang Mode to
download configuration data to the FPGA which would define its hardware function, then after the FPGA
device is configured the FT232B can switch back into UART interface mode to allow the programmed
FPGA device to communicate with the PC over USB. This approach allows a customer to create a
“generic” USB peripheral whose hardware function can be defined under control of the application
software. The FPGA based hardware can be easily upgraded or totally changed simply by changing the
FPGA configuration data file. Application notes, software and development modules for this application
area will be available from FTDI and other 3rd parties.
PreScaler Divide By 1 Fix. The previous device had a problem when the integer part of the divisor was
set to 1. In the 2nd generation device setting the prescaler value to 1 gives a baud rate of 2 million baud
and setting it to zero gives a baud rate of 3 million baud. Non-integer division is not supported with
divisor values of 0 and 1.
Less External Support Components. As well as eliminating the RCCLK RC network, and for most
applications the need for an external reset circuit, we have also eliminated the requirement for a 100K
pull-up on EECS to select 6MHz operation. When the FT232B is being used without the configuration
EEPROM, EECS, EESK and EEDATA can now be left n/c. For circuits requiring a long reset time (where the
device is reset externally using a reset generator I.C., or reset is controlled by the IO port of a MCU,
FPGA or ASIC device) an external transistor circuit is no longer required as the 1.5k pull-up resistor on
USBDP can be wired to the RSTOUT# pin instead of to 3.3V. Note : RSTOUT# drives out at 3.3V level,
not at 5V VCC level. This is the preferred configuration for new designs.
Extended EEPROM Support. The previous generation of devices only supported EEPROM of type 93C46
(64 x 16 bit). The new devices will also work with EEPROM type 93C56 (128 x 16 bit) and 93C66 (256 x
16 bit). The extra space is not used by the device, however it is available for use by other external MCU /
logic whilst the FT232B is being held in reset.
USB 2.0 (full speed option). A new EEPROM based option allows the FT232B to return a USB 2.0
device descriptor as opposed to USB 1.1. Note : The device would be a USB 2.0 Full Speed device
(12Mb/s) as opposed to a USB 2.0 High Speed device (480Mb/s).
Multiple Device Support without EEPROM. When no EEPROM (or a blank or invalid EEPROM) is
attached to the device, the FT232B no longer gives a serial number as part of its USB descriptor. This
allows multiple devices to be simultaneously connected to the same PC. However, we still highly
recommend that EEPROM is used, as without serial numbers a device can only be identified by which hub
port in the USB tree it is connected to which can change if the end user re-plugs the device into a
different port
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4.2 Functional Block Descriptions
The following paragraphs detail each function within the FT232B. Please refer to the block diagram shown
in Figure 2.1 .
The 3.3V LDO Regulator generates the 3.3 volt reference voltage for driving the USB transceiver cell
output buffers. It requires an external decoupling capacitor to be attached to the 3V3OUT regulator
output pin. It also provides 3.3V power to the RSTOUT# pin. The main function of this block is to power
the USB Transceiver and the Reset Generator Cells rather than to power external logic. However,
external circuitry requiring 3.3V nominal at a current of not greater than 5mA could also draw its power
from the 3V3OUT pin if required.
USB Transceiver. The USB Transceiver Cell provides the USB 1.1 / USB 2.0 full-speed physical interface
to the USB cable. The output drivers provide 3.3 volt level slew rate control signalling, whilst a differential
receiver and two single ended receivers provide USB data in, SEO and USB Reset condition detection.
USB DPLL. The USB DPLL cell locks on to the incoming NRZI USB data and generates recovered clock
and data signals for the Serial Interface Engine (SIE) block.
6MHz Oscillator. The 6MHz Oscillator cell generates a 6MHz reference clock input to the x8 Clock
multiplier from an external 6MHz crystal or ceramic resonator
X8 Clock Multiplier. The x8 Clock Multiplier takes the 6MHz input from the Oscillator cell and generates
a 12MHz reference clock for the SIE, USB Protocol Engine and UART FIFO controller blocks. It also
generates a 48MHz reference clock for the USB DPPL and the Baud Rate Generator blocks.
Serial Interface Engine (SIE). The Serial Interface Engine (SIE) block performs the parallel to serial
and serial to parallel conversion of the USB data. In accordance with the USB 2.0 specification, it
performs bit stuffing/un-stuffing and CRC5/CRC16 generation. It also checks the CRC on the USB data
stream.
USB Protocol Engine. The USB Protocol Engine manages the data stream from the device USB control
endpoint. It handles the low level USB protocol (Chapter 9) requests generated by the USB host
controller and the commands for controlling the functional parameters of the UART.
Dual Port TX Buffer (128 bytes). Data from the USB data out endpoint is stored in the Dual Port TX
buffer and removed from the buffer to the UART transmit register under control of the UART FIFO
controller.
Dual Port RX Buffer (384 bytes). Data from the UART receive register is stored in the Dual Port RX
buffer prior to being removed by the SIE on a USB request for data from the device data in endpoint.
UART FIFO Controller. The UART FIFO controller handles the transfer of data between the Dual FIFO RX
and TX buffers and the UART transmit and receive registers.
UART. The UART performs asynchronous 7/8 bit Parallel to Serial and Serial to Parallel conversion of the
data on the RS232 (RS422 and RS485) interface. Control signals supported by the UART include RTS,
CTS, DTR, DSR, DCD and RI. The UART provides a transmitter enable control signal (TXDEN) to assist
with interfacing to RS485 transceivers. The UART supports RTS/CTS, DTR/DSR and X-On/X-Off
handshaking options. Handshaking, where required, is handled in hardware to ensure fast response
times. The UART also supports the RS232 BREAK setting and detection conditions.
Baud Rate Generator. The Baud Rate Generator provides a x16 clock input to the UART from the
48MHz reference clock and consists of a 14 bit prescaler and 3 register bits which provide fine tuning of
the baud rate (used to divide by a whole number plus a fraction). This determines the Baud Rate of the
UART which is programmable from 183 baud to 3M baud.
RESET Generator. The Reset Generator Cell provides a reliable power-on reset to the device internal
circuitry on power up. RESET# input and RSTOUT# output are provided to allow other devices to reset
the FT232B to reset other devices respectively. During reset, RSTOUT# is driven low, otherwise it drives
out at the 3.3V provided by the onboard regulator. RSTOUT# can be used to control the 1.5k pull-up on
USBDP directly where delayed USB enumeration is required. It can also be used to reset other devices.
RSTOUT# will stay high-impedance for approximately 5ms after VCC has risen above 3.5V AND the
device oscillator is running AND RESET# is high. RESET# should be tied to VCC unless it is a requirement
to reset the device from external logic or an external reset generator IC.
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EEPROM interface. Though the FT232B will work without the optional EEPROM, an external 93C46
(93C56 or 93C66) EEPROM can be used to customise the USB VID, PID, Serial Number, Product
Description Strings and Power Descriptor value of the FT232B for OEM applications. Other parameters
controlled by the EEPROM include Remote Wake Up, Soft Pull Down on Power-Off and USB 2.0 descriptor
modes. The EEPROM should be a 16 bit wide configuration such as a MicroChip 93LC46B or equivalent
capable of a 1Mb/s clock rate at VCC = 4.35V to 5.25V. The EEPROM is programmable-on board over
USB using a utility available from FTDI’s web site (http://www.ftdichip.com). This allows a blank part to be
soldered onto the PCB and programmed as part of the manufacturing and test process. If no EEPROM is
connected (or the EEPROM is blank), the FT232B will use its built-in default VID, PID Product Description
and Power Descriptor Value. In this case, the device will not have a serial number as part of the USB
descriptor.
.-" FTDI 5.. Chip
Copyright © 2011 Future Technology Devices International Limited 14
Document No.: FT_000329
FT232BL/BQ USB UART IC Datasheet Version 2.2
Clearance No.: FTDI# 171
5 Devices Characteristics and Ratings
5.1 Absolute Maximum Ratings
The absolute maximum ratings for the FT232B devices are as follows. These are in accordance with the
Absolute Maximum Rating System (IEC 60134). Exceeding these may cause permanent damage to the
device.
Parameter
Value
Unit
Storage Temperature
-65 to +150
˚C
Floor Life (Out of Bag) At Factory Ambient
(30°C / 60% Relative Humidity)
192
(MSL 3 Compliant)
**Note 2
Hours
Ambient Temperature (Power Applied)
0 to +70
˚C
M.T.B.F. (at 35°C)
247484
≈ 28
Hours
Years
VCC Supply Voltage
-0.5 to +6.00
V
DC Input Voltage USBDP and USBDM
-0.5 to +3.8
V
DC Input Voltage High Impedance Bidirectional
-0.5 to + (VCC +0.5)
V
DC Input Voltage All Other Inputs
-0.5 to + (VCC +0.5)
V
DC Output Current Outputs
24
mA
DC Output Current Low Impedance
Bidirectional
24
mA
Power Dissipation
(VCC = 5.25V)
500
mW
Electrostatic Discharge Voltage
(Human Body Model) (I<1uA)
±3000
V
Latch Up Current
(Vi = +/- 10V maximum, for 10ms)
±200
mA
Table 5.1 Absolute Maximum Ratings
**Note 2 If devices are stored out of the packaging beyond this time limit the devices should be baked
before use. Refer to JEDEC 033b for baking details.
-'" FTDI 3“. Chip
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FT232BL/BQ USB UART IC Datasheet Version 2.2
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5.2 DC Characteristics
DC Characteristics (Ambient Temperature = 0˚C to 70˚C)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
VCC1
VCC Operating Supply
Voltage
4.35
5
5.25
V
VCC2
VCCIO Operating Supply
Voltage
3.0
---
5.25
V
Icc1
Operating Supply
Current
---
25
---
mA
Normal Operation
Icc2
Operating Supply
Current
---
180
200
μA
USB Suspend
**Note 3
Table 5.2 Operating Voltage and Current
**Note 3 Supply current excludes the 200uA nominal drawn by the external pull-up resistor on
USBDP.
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
3.2
4.1
4.9
V
I source = 2mA
Vol
Output Voltage Low
0.3
0.4
0.6
V
I sink = 2mA
Vin
Input Switching
Threshold
1.0
1.2
1.5
V
**Note 4
Vhys
Input Switching
Hysteresis
50
55
60
mV
Table 5.3 UART IO Pin Characteristics (VCCIO = +5.0V)
**Note 4 Inputs have an internal 200K pull-up resistor to VCCIO.
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
2.2
2.7
3.2
V
I source = 1mA
Vol
Output Voltage Low
0.3
0.4
0.5
V
I sink = 2mA
Vin
Input Switching
Threshold
1.0
1.2
1.5
V
**Note 4
Vhys
Input Switching
Hysteresis
20
25
30
mV
Table 5.4 UART IO Pin Characteristics (VCCIO = +3.0 to +3.6V)
**Note 4 Inputs or IO pin in input mode have an internal 200K pull-up resistor to VCCIO.
-'" FTDI 3“. Chip
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Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
4.0
-
5.0
V
Fosch = 6MHZ
Vol
Output Voltage Low
0.1
-
1.0
V
Fosch = 6MHZ
Vin
Input Switching
Threshold
1.8
2.5
3.2
V
Table 5.5 XTIN / XTOUT Pin Characteristics
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
3.2
4.1
4.9
V
I source = 2mA
Vol
Output Voltage Low
0.3
0.4
0.6
V
I sink = 2mA
Vin
Input Switching
Threshold
1.3
1.6
1.9
V
Vhys
Input Switching
Hysteresis
50
55
60
mV
**Note 5
Table 5.6 RESET#, TEST, EECS, EESK, EEDATA Pin Characteristics
**Note 5 EECS, EESK and EEDATA pins have an internal 200K pull-up resistor to VCC
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
3.0
-
3.6
V
I source = 2mA
Vol
Output Voltage Low
0.3
-
0.6
V
I sink = 2mA
Table 5.7 RSTOUT Pin Characteristics (VCCIO = +1.8V, Standard Drive Level)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Uvoh
IO Pins Static Output (
High)
2.8
-
3.6
V
RI = 1.5K to 3V3Out ( D+)
I = 15K to GND ( D-)
Uvol
IO Pins Static Output (
Low)
0
-
0.3
V
RI = 1.5K to 3V3Out ( D+)
I = 15K to GND ( D-)
Uvse
Single Ended Rx
Threshold
0.8
-
2.0
V
Ucom
Differential Common
Mode
0.8
-
2.5
V
UVDif
Differential Input
Sensitivity
0.2
-
V
UdrvZ
Driver Output Impedance
29
-
44
Ohms
**Note 6
Table 5.8 USB I/O Pin Characteristics
**Note 6 Driver Output Impedance includes the external 27R series resistors on USBDP and USBDM
pins.
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FT232BL/BQ USB UART IC Datasheet Version 2.2
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6 USB Power Configurations
The following sections illustrate possible USB power configurations for the FT232B.
6.1 USB Bus Powered Configuration
Figure 6.1 Bus Powered Configuration
Figure 6.1 illustrates a typical USB bus powered configuration. A USB Bus Powered device gets its power
from the USB bus. Basic rules for USB Bus power devices are as follows:
a) On plug-in, the device must draw no more than 100mA
b) On USB Suspend the device must draw no more than 500uA (2.5mA for devices configured to
support remote wake-up).
c) A Bus Powered High Power Device (one that draws more than 100mA) should use the PWREN#
pin to keep the current below 100mA on plug-in and 500uA(2.5mA) on USB suspend.
d) A device that consumes more than 100mA cannot be plugged into a USB Bus Powered Hub
e) No device can draw more that 500mA from the USB Bus.
The power descriptor in the EEPROM should be programmed to match the current draw of the device.
PWRCTL (pin 14) is pulled low to configure the device with a USB Bus Power descriptor. A Ferrite Bead is
connected in series with USB power to prevent noise from the device and associated circuitry (EMI) being
radiated down the USB cable to the Host. The value of the Ferrite Bead depends on the total current
required by the circuit a suitable range of Ferrite Beads is available from Steward (www.steward.com)
for example Steward Part # MI0805K400R-00, also available as DigiKey Part # 240-1035-1.
usa B 410R " " vcc 2 3 13 o.1uF 3 v v v A 4 c c c v c c c c I swam o c 4r: USBDM USE DP FT232B‘ 10k RSTOUT# 4 vcc RESEW A vcc—C 14 G c G POWERCTL N N N , D u u 0.1m= n.1uF 1|7uF 9 11 29 Decoupling Capacitors
Copyright © 2011 Future Technology Devices International Limited 18
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FT232BL/BQ USB UART IC Datasheet Version 2.2
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6.2 Self Powered Configuration
Figure 6.2 Self Powered Configuration
Figure 6.2 illustrates a typical USB self powered configuration. A USB Self Powered device gets its power
from its own POWER SUPPLY and does not draw current from the USB bus. The basic rules for USB Self
power devices are as follows:
a) A Self-Powered device should not force current down the USB bus when the USB Host or Hub
Controller is powered down.
b) A Self Powered Device can take as much current as it requires during normal operation and USB
suspend as it has its own POWER SUPPLY.
c) A Self Powered Device can be used with any USB Host and both Bus and Self Powered USB Hubs
PWRCTL (pin 14) is pulled high to configure the device with a USB Bus Power descriptor. The power
descriptor in the EEPROM should be programmed to a value of zero. The USB power descriptor option in
the EEPROM should be programmed to a value of zero (self powered).
To meet requirement, the 1.5 K pull-up resistors on USBDP is connected to RSTOUT# as per the bus-
power circuit. However, the USB Bus Power is used to control the RESET# Pin of the FT232B device.
When the USB Host or Hub is powered up RSTOUT# will pull the 1.5K resistor on USBDP to 3.3V, thus
identifying the device as a full speed device to USB. When the USB Host or Hub power is off, RESET# will
go low and the device will be held in reset. As RESET# is low, RSTOUT# will also be low, so no current
will be forced down USBDP via the 1.5K pull-up resistor when the host or hub is powered down. Failure to
do this may cause some USB host or hub controllers to power up erratically.
Note: When the FT232B is in reset, the UART interface pins all go tri-state. These pins have internal 200K
pull-up resistors to VCCIO, so they will gently pull high unless driven by some external logic.
USB "8' FTDI Chip Conn-cm I 'L DluF 3 Jv L00 Rte-ulna 3.3V Pow" m Emmi Logic In W . 0nd $ I 0.1uF Fenih Bcld ‘70R 3 l 2‘ ‘3 30 v v v A c c c v I c c c c w s 5 mom ' c I n r o I FT23ZB ° us: on 7 USE DP
Copyright © 2011 Future Technology Devices International Limited 19
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FT232BL/BQ USB UART IC Datasheet Version 2.2
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6.3 Interfacing to 3.3V Logic
6.3.1 Bus Powered Circuit with 3.3V logic drive / supply voltage
Figure 6.3 Bus Powered Circuit with 3.3V logic drive / supply voltage
Figure 6.3 shows how to configure the FT232B to interface with a 3.3V logic device. In this example, a
discrete 3.3V regulator is used to supply the 3.3V logic from the USB supply. VCCIO is connected to the
output of the 3.3V regulator, which in turn will cause the UART interface IO pins to drive out at 3.3V
level. For USB bus powered circuits some considerations have to be taken into account when selecting
the regulator:
a) The regulator must be capable of sustaining its output voltage with an input voltage of 4.35 volts.
A Low Drop Out (LDO) regulator must be selected.
b) The quiescent current of the regulator must be low in order to meet the USB suspend total
current requirement of <= 500uA during USB suspend.
An example of a regulator family that meets these requirements is the MicroChip MCP1700 Series. These
devices can supply up to 250mA current and have a quiescent current of under 1uA.
In some cases, where only a small amount of current is required (< 5mA) , it may be possible to use the
in-built regulator of the FT232B to supply the 3.3v without any other components being required. In this
case, connect VCCIO to the 3v3OUT pin of the FT232B.
Note: It should be emphasized that the 3.3V supply for VCCIO in a bus powered design with a 3.3V logic
interface should come from an LDO which is supplied by the USB bus, or from the 3V3OUT pin of the
FT232B, and not from any other source.
USE ”B" Conmclof Ma; r 4K7 10K 0.1 MP _ .10uF mcoupnng Capacilovs VCCSV —. 470R VCCSV —. 3|) 26 13 A v v v v c c c c c c c c I :5va ° FT2323 USBDM usanp vac“ ll PWRC'I'L RSTOUTI RESET! A e G e u N u n n o S 17 29
Copyright © 2011 Future Technology Devices International Limited 20
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FT232BL/BQ USB UART IC Datasheet Version 2.2
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6.3.2 Self Powered Circuit with 3.3V logic drive / supply
Figure 6.4 Self Powered Circuit with 3.3V logic drive / supply
Figure 6.4 is an example of a USB self powered design with 3.3V interface. In this case VCCIO is supplied
by an external 3.3V supply in order to make the device IO pins drive out at 3.3V logic level, thus allowing
it to be connected to a 3.3V MCU or other external logic. A USB self powered design uses its own power
supplies, and does not draw any of its power from the USB bus. In such cases, no special care need be
taken to meet the USB suspend current (0.5 mA) as the device does not get its power from the USB port.
As with bus powered 3.3V interface designs, in some cases, where only a small amount of current is
required (<5mA), it may be possible to use the in-built regulator of the FT232B to supply the 3.3V without
any other components being required. In this case, connect VCCIO to the 3v3OUT pin of the FT232B.
Note that in this case PWRCTL is pulled up to VCCIO, not VCC.
FTDI Chip P-Chanml PW" Switch-d 5v PM to Emmal Logic I I ur our San sun m Circull USB '1!" Conmclol www.micrel .com
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6.4 Bus Powered Circuit (<=100mA) with Power Control
Figure 6.5 Bus Powered with Power Switching Configuration
USB Bus powered circuits need to be able to power down in USB suspend mode in order to meet the <=
500uA total suspend current requirement (including external logic). This limit is 2.5mA for devices that
support remote wake-up. Some external logic can power itself down into a low current state by
monitoring the PWREN# pin. For external logic that cannot power itself down in that way, the FT232B
provides a simple but effective way of turning off power to external circuitry during USB suspend.
Figure 8.3 shows how to use a discrete P-Channel Logic Level MOSFET to control the power to external
logic circuits. A suitable device could be a Fairchild NDT456P, or International Rectifier IRLML6402, or
equivalent. It is recommended that a “soft start” circuit consisting of a 1K series resistor and a 0.1 uF
capacitor are used to limit the current surge when the MOSFET turns on. Without the soft start circuit
there is a danger that the transient power surge of the MOSFET turning on will reset the FT232B, or the
USB host / hub controller. The values used here allow attached circuitry to power up with a slew rate of
~12.5 V per millisecond, in other words the output voltage will transition from GND to 5V in
approximately 400 microseconds.
Alternatively, a dedicated power switch i.c. with inbuilt “soft-start” can be used instead of a MOSFET. A
suitable power switch I.C. for such an application would be a Micrel (www.micrel.com) MIC2025-2BM or
equivalent.
Please note the following points in connection with power controlled designs
a) The logic to be controlled must have its own reset circuitry so that it will automatically reset itself
when power is re-applied on coming out of suspend.
b) Set the Pull-down on Suspend option in the FT232B’s EEPROM.
c) For USB high-power bus powered device (one that consumes greater than 100 mA, and up to 500
mA of current from the USB bus), the power consumption of the device should be set in the max
power field in the EEPROM. A high-power bus powered device must use this descriptor in the
EEPROM to inform the system of its power requirements.
d) For 3.3V power controlled circuits VCCIO must not be powered down with the external circuitry
(PWREN# gets its VCC supply from VCCIO). Either connect the power switch between the output
of the 3.3V regulator and the external 3.3V logic OR if appropriate power VCCIO from the
3V3OUT pin of the FT232B.
27 3-Pln Rtlonalcv SMHX F2... 18 FT23ZB XTIN XTOUT 27p: $— 2 - Pin Rolonalol —— M Cryiul mu: zvpr J,— [22:22:] XTOUT
Copyright © 2011 Future Technology Devices International Limited 22
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7 Device Configuration Examples
The following sections illustrate device configurations for the FT245BM.
7.1 Oscillator Configurations
Figure 7.1 3 Pin Ceramic Resonator Configuration Figure 7.2 Crystal or 2 Pin
Ceramic Resonator Configuration
Figure 7.1 illustrates how to use the FT232B with a 3-Pin Ceramic Resonator. A suitable part would be a
ceramic resonator from Murata’s CERALOCK range or equivalent. 3-Pin ceramic resonators have the load
capacitors built into the resonator so no external loading capacitors are required. This makes for an
economical configuration. The accuracy of this Murata ceramic resonator is +/- 0.1% and it is specifically
designed for USB full speed applications. A 1 MegaOhm loading resistor across XTIN and XTOUT is
recommended in order to guarantee this level of accuracy.
Figure 7.2 illustrates how to use the FT232B with a 6MHz Crystal or 2-Pin Ceramic Resonator. These
devices do not have in-built loading capacitors. They must be added between XTIN, XTOUT and GND as
shown. A value of 27pF is shown as the capacitor in the example this will be good for many crystals and
some resonators but do select the value based on the manufacturer’s recommendations wherever
possible. If using a crystal, use a parallel cut type. If using a resonator, see the previous note on
frequency accuracy.
FTDI Chip FT23ZB vcc EEDKM-owwut“ cg vcc z u no 2n: 3 on NC 4 not" 6'”
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7.2 EEPROM Configuration
Figure 7.3 EEPROM Configuration
Figure 7.3 illustrates how to connect the FT232B to the 93C46 (93C56 or 93C66) EEPROM. EECS (pin 32)
is directly connected to the chip select (CS) pin of the EEPROM. EESK (pin 1) is directly connected to the
clock (SK) pin of the EEPROM. EEDATA (pin 2) is directly connected to the Data In (Din) pin of the
EEPROM. There is a potential condition whereby both the Data Output (Dout) of the EEPROM can drive out
at the same time as the EEDATA pin of the FT232B. To prevent potential data clash in this situation, the
Dout of the EEPROM is connected to EEDATA of the FT232B via a 2.2K resistor.
Following a power-on reset or a USB reset, the FT232B will scan the EEPROM to find out (a) if an EEPROM
is attached to the Device and (b) if the data in the device is valid. If both conditions are true, then the
FT232B will use the data in the EEPROM, otherwise it will use its built-in default values. When a valid
command is issued to the EEPROM from the FT232B, the EEPROM will acknowledge the command by
pulling its Dout pin low. In order to check for this condition, it is necessary to pull Dout high using a 10K
resistor. If the command acknowledge doesn’t happen then EEDATA will be pulled high by the 10K resistor
during this part of the cycle and the device will detect an invalid command or no EEPROM present.
There are two varieties of these EEPROM’s from many sources such as Microchip, STMicro, ISSI etc. – one
is configured as being 16 bits wide, the other is configured as being 8 bits wide. The FT232B requires
EEPROMs with a 16-bit wide configuration such as the Microchip 93LC46B device. The EEPROM must be
capable of reading data at a 1Mb clock rate at a supply voltage of 4.35V to 5.25V. Most
available parts are capable of this.
Check the manufacturers’ data sheet to find out how to connect pins 6 and 7 of the EEPROM. Some
devices specify these as no-connect, others use them for selecting 8 / 16 bit mode or for test functions.
Some other parts have their pin out rotated by 90˚ . It is recommended to select the required part and its
options carefully.
It is possible to “sharethe EEPROM between the FT232B and another external device such as an MCU.
However, this can only be done when the FT232B is held in the reset condition as it tri-states its EEPROM
interface at that time. A typical configuration would use four bit’s of an MCU IO Port. One bit would be
used to hold the FT232B reset (using RESET#) on power-up, the other three would connect to the EECS,
EESK and EEDATA pins of the FT232B in order to read / write data to the EEPROM at this time. Once the
MCU has read / written the EEPROM, it would take RESET# high to allow the FT232B to configure itself and
enumerate over USB.
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Copyright © 2011 Future Technology Devices International Limited 24
Document No.: FT_000329
FT232BL/BQ USB UART IC Datasheet Version 2.2
Clearance No.: FTDI# 171
8 UART Interface Configurations
The following sections illustrate possible UART configurations for the FT232B.
8.1 USB RS232 Converter Configuration
Figure 8.1 USB-RS232 Converter Configuration
Figure 7.1 illustrates how to connect the UART interface of the FT232B to a TTL RS232 Level Converter
I.C. to make a USB RS232 converter using the popular “213” series of TTL to RS232 level converters.
These devices have 4 transmitters and 5 receivers in a 28-pin SSOP package and feature an in-built
voltage converter to convert the 5v (nominal) VCC to the ±9 volts required by RS232. An important
feature of these devices is the SHDN# pin which can power down the device to a low quiescent current
during USB suspend mode.
The device used in the example is a Exar/Sipex SP213EHCA which is capable of RS232 communication at
up to 500K baud. If a lower baud rate is acceptable, then several pin compatible alternatives are
available such as Sipex SP213ECA , Maxim MAX213CAI and Analog Devices ADM213E which are good for
communication at up to 115,200 baud. If a higher baud rate is desired, use a Maxim MAX3245CAI part
which is capable of RS232 communication at rates of up to 1M baud. The MAX3245 is not pin compatible
with the 213 series devices, also its SHDN pin is active high so connect this to PWREN# instead of
SLEEP#.
FTDI Chip vcc FT23ZB 1t spm DBS-M mam ‘5 [— W m SLEEP. 1° n3 9 mp W TXD 25 9/] 11 R 12 non m 24—1 ID. mu 7 ms: 23 6% 47 22 —T— vcc CT“ 14 SP‘S‘ 6““ 21 um — m mm ”5'“ L D ’ msr crsr L 11 Dc" mm 15 R 12 R“ — 1e 5 1 cm men
Copyright © 2011 Future Technology Devices International Limited 25
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8.2 USB RS422 Converter Configuration
Figure 8.2 USB-RS422 Converter Configuration
Figure 8.2 illustrates how to connect the UART interface of the FT232B to a TTL RS422 Level Converter
I.C. to make a USB RS422 converter. There are many such level converter devices available this
example uses Exar/Sipex SP491 devices which have enables on both the transmitter and receiver.
Because the transmitter enable is active high, it is connected to the SLEEP# pin. The receiver enable is
active low and is connected to the PWREN# pin. This ensures that both the transmitters and receivers are
enabled when the device is active, and disabled when the device is in USB suspend mode. If the design is
USB BUS powered, it may be necessary to use a P-Channel logic level MOSFET (controlled by PWREN#) in
the VCC line of the SP491 devices to ensure that the USB standby current of 500uA is met.
The SP491 is good for sending and receiving data at a rate of up to 5M Baud in this case the maximum
rate is limited to 3M Baud by the FT232B
FTDI Chip FT232B DBQ-M PWRENI! 15 VCC 8 spam SLEEPII 1° 3 _._ ma TXD 25 ‘ D 2 S RXD 2‘ DP 23 R GND RTSk 22 5 c150 $ 120R DTRU N a “ E Z S I—éo DSR‘ L Dcnu ‘9 RH 18 16 TXDEN
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8.3 USB RS485 Converter Configuration
Figure 8.3 USB-RS485 Converter Configuration
Figure 7.3 illustrates how to connect the UART interface of the FT232B to a TTL RS485 Level Converter
I.C. to make a USB => RS485 converter. This example uses the Exar/Sipex SP481 device but there are
similar parts available from Maxim and Analog Devices amongst others. The SP481 is a RS485 device in a
compact 8 pin SOP package. It has separate enables on both the transmitter and receiver. With RS485,
the transmitter is only enabled when a character is being transmitted from the UART. The TXDEN pin on
the FT232B is provided for exactly that purpose and so the transmitter enable is wired to TXDEN. The
receiver enable is active low, so it is wired to the PWREN# pin to disable the receiver when in USB
suspend mode.
RS485 is a multi-drop network i.e. many devices can communicate with each other over a single two
wire cable connection. The RS485 cable requires to be terminated at each end of the cable. A link is
provided to allow the cable to be terminated if the device is physically positioned at either end of the
cable.
In this example the data transmitted by the FT232B is also received by the device that is transmitting.
This is a common feature of RS485 and requires the application software to remove the transmitted data
from the received data stream. With the FT232B it is possible to do this entirely in hardware simply
modify the schematic so that RXD of the FT232B is the logical OR of the SP481 receiver output with
TXDEN using an HC32 or similar logic gate.
»_ Chip —.— VCCIO LEDSZ 220R FT23ZB FT23ZB mam TXLEM '2 RXLEN RXLEDI ”
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9 LED Interface Configuration
Figure 9.1 Dual LED Configuration Figure 9.2 Single LED
Configuration
The FT232B has two IO pins dedicated to controlling LED status indicators, one for transmitted data the
other for received data. When data is being transmitted / received the respective pins drive from tri-state
to low in order to provide indication on the LEDs of data transfer. A digital one-shot timer is used so that
even a small percentage of data transfer is visible to the end user.
Figure 9.1 shows a configuration using two individual LED’s – one for transmitted data the other for
received data.
In figure 9.2, transmit and receive LED indicators are wire-OR’ed together to give a single LED indicator
which indicates any transmit or receive data activity.
Another possibility (not shown here) is to use a 3 pin common anode tri-color LED based on the circuit in
Figure 9.2 to have a single LED that can display activity in a variety of colors depending on the ratio of
transmit activity compared to receive activity.
Note that the LED’s are connected to VCCIO.
"i: FTDI 1.60 MAX Fln81: O HHHHHHH finnn’nnnn E FTDI FT23ZBL XXYY HHHHHHHH J25 —f ‘ 0.6 u. 0.15 r” 0.37 N- 0.07 I --I' "l wfijELfix 0.35 01- 0.05
Copyright © 2011 Future Technology Devices International Limited 28
Document No.: FT_000329
FT232BL/BQ USB UART IC Datasheet Version 2.2
Clearance No.: FTDI# 171
10 Package Parameters
10.1 LQFP Package Dimension
The FT232BL is supplied in a 32 pin LQFP package as standard.
Figure 10.1 32 LQFP Package Dimensions
This package has a 7mm x 7mm body (9mm x 9mm including leads) with leads on a 0.8mm pitch. The
above drawing shows the LQFP-32 package all dimensions are in millimeters. Note that there are two
date code formats used XXYY = Date Code where XX = 2 digit year number, YY = 2 digit week number;
or XYY-N where X = 1 digit year. Number, YY = 2 digit week number, and N is an integer.
The FT232BL is fully compliant with the European Union RoHS directive.
".-" FTDI ‘- Chip EFF-DI 5"" FT23ZBQ _'ILILH_|L|LILI|'_ E E ”“1: C :1 C um :I I: :I I: E E om: _.'Immflnnn|._ om? nnnnnnnn 02mm
Copyright © 2011 Future Technology Devices International Limited 29
Document No.: FT_000329
FT232BL/BQ USB UART IC Datasheet Version 2.2
Clearance No.: FTDI# 171
10.2 QFN Package Dimension
The FT232BQ is supplied in a 32 pin QFN package as standard.
Figure 10.2 32 LQFP Package Dimensions
The FT232BQ is supplied in lead (Pb) free, leadless QFN32 package. This package has a 5 mm x 5 mm
body with no protruding pins, and is ideal for for projects where package area is critical. In the above
drawing all dimensions are in millimetres. Note that two date code formats are used XXYY = Date Code
where XX = 2 digit year number, YY = 2 digit week number; or XYY-1 where X = 1 digit year. Number,
YY = 2 digit week number. The FT232BQ is fully compliant with the European Union RoHS directive.
E-maii (Sales) salesl@ftdichip.com supportletdichigtcom E-maii (General Enquiries) adminl @ftdichip.com Web Site URL ntt : wwwtftdicni .com Web Shop URL ntt : wwwtftdicni .com E-maii (Sales) tw.salesl@ftdichip.com E-maii (Support) tw.sugport1@ftdichigtcom E-maii (General Enquiries) tw.admin1@ftdichig.com Web Site URL ntt : wwwtftdicni .com E-Mail (Saies) us.sa|es @ftdichip.c0m E-Mail (Support) us.supgort@ftdichip.com E-Mail (General Enquiries) us.admin@ftdicnip.com Web Site URL ntt : wwwtftdichi .com E-maii (Sales) cn.sales @ftdichigtcom E-maii (Support) cn.supgort@ftdichip.com E-maii (General Enquiries) cn.admin@ftdichip.com Web Site URL ntt : wwwtftdicni .com
Copyright © 2011 Future Technology Devices International Limited 30
Document No.: FT_000329
FT232BL/BQ USB UART IC Datasheet Version 2.2
Clearance No.: FTDI# 171
11 Contact Information
Head Office Glasgow, UK
Future Technology Devices International Limited
Unit 1, 2 Seaward Place, Centurion Business Park
Glasgow G41 1HH
United Kingdom
Tel: +44 (0) 141 429 2777
Fax: +44 (0) 141 429 2758
E-mail (Sales)
sales1@ftdichip.com
E-mail (Support)
support1@ftdichip.com
E-mail (General Enquiries)
admin1@ftdichip.com
Web Site URL
http://www.ftdichip.com
Web Shop URL
http://www.ftdichip.com
Branch Office Taipei, Taiwan
Future Technology Devices International Limited (Taiwan)
2F, No. 516, Sec. 1, NeiHu Road
Taipei 114
Taiwan , R.O.C.
Tel: +886 (0) 2 8791 3570
Fax: +886 (0) 2 8791 3576
E-mail (Sales)
tw.sales1@ftdichip.com
E-mail (Support)
tw.support1@ftdichip.com
E-mail (General Enquiries)
tw.admin1@ftdichip.com
Web Site URL
http://www.ftdichip.com
Branch Office Hillsboro, Oregon, USA
Future Technology Devices International Limited (USA)
7235 NW Evergreen Parkway, Suite 600
Hillsboro, OR 97123-5803
USA
Tel: +1 (503) 547 0988
Fax: +1 (503) 547 0987
E-Mail (Sales)
us.sales@ftdichip.com
E-Mail (Support)
us.support@ftdichip.com
E-Mail (General Enquiries)
us.admin@ftdichip.com
Web Site URL
http://www.ftdichip.com
Branch Office Shanghai, China
Future Technology Devices International Limited (China)
Room 408, 317 Xianxia Road,
Shanghai, 200051
China
Tel: +86 21 62351596
Fax: +86 21 62351595
E-mail (Sales)
cn.sales@ftdichip.com
E-mail (Support)
cn.support@ftdichip.com
E-mail (General Enquiries)
cn.admin@ftdichip.com
Web Site URL
http://www.ftdichip.com
Distributor and Sales Representatives
Please visit the Sales Network page of the FTDI Web site for the contact details of our distributor(s) and
sales representative(s) in your country.
FTDI - _ Chip http: www.ftdichip.com Documents AppNotes AN 100 Using The FT232 245R With External Dsc(FT 000067 .Qdf httD: www.ftdichiD.com Documents AppNotes AN 103 FTDI Drivers Installation Guide for VISTAiFT 000080 .Qdf httD: www.ftdichiD.com Documents AppNotes AN 104 FTDI Drivers Installation Guide for WindowsX P FT 000093 .Qdf http: www.ftdichip.com Documents AppNotes AN 107 AdvancedDriveertions AN 000073de htto: www.ftdichiD.com Documents ADDNOtes AN 120 Aliasino VCP Baud Ratesodf htto: www.ftdichiD.com Documents ADDNOtes AN23ZB-01 BitBanq.Ddf httD: www.ftdichiD.com Documents ADDNotes AN23ZB-05 BaudRates.Ddf http: www.ftdichip.com Documents InstallGuides.htm httD: ftdichiotcom Documents TechnicalNotes TN 100 USB VID-PID Guidelines.Ddf http: ftdichiptcom Documents TechnicalNotes TN 102 DEM Technical Support Requirements for FTDI Products.gdf httD: www.ftdichip.com Documents TechnicalNotes TN 104 Guidea/u20tofllu20Debquincl Customers Fa iled Driver ”/oZOInstallation D/UZOOH “/u20Windows.Ddf
Copyright © 2011 Future Technology Devices International Limited 31
Document No.: FT_000329
FT232BL/BQ USB UART IC Datasheet Version 2.2
Clearance No.: FTDI# 171
Appendix A References
Useful Application Notes
AN-100, “Using the FT232/FT245R with External Crystal or Oscillator”
http://www.ftdichip.com/Documents/AppNotes/AN_100_Using_The_FT232_245R_With_External_Osc(FT_
000067).pdf
AN_103, “FTDI Drivers Installation Guide for VISTA”.
http://www.ftdichip.com/Documents/AppNotes/AN_103_FTDI_Drivers_Installation_Guide_for_VISTA(FT_
000080).pdf
AN_104, “FTDI Drivers Installation Guide for Windows XP”.
http://www.ftdichip.com/Documents/AppNotes/AN_104_FTDI_Drivers_Installation_Guide_for_WindowsX
P(FT_000093).pdf
AN_107, “Advanced Driver Options”.
http://www.ftdichip.com/Documents/AppNotes/AN_107_AdvancedDriverOptions_AN_000073.pdf
AN_120 Aliasing VCP Baud Rates
http://www.ftdichip.com/Documents/AppNotes/AN_120_Aliasing_VCP_Baud_Rates.pdf
AN232R-01, “FT232BM/ FT245BM Bit-Bang Mode”.
http://www.ftdichip.com/Documents/AppNotes/AN232B-01_BitBang.pdf
Configuring FT232R, FT2232 and FT232BM Baud Rates
http://www.ftdichip.com/Documents/AppNotes/AN232B-05_BaudRates.pdf
Installation Guides
http://www.ftdichip.com/Documents/InstallGuides.htm
Useful Technical Notes
TN_100, “USB Vendor ID/Product ID Guidelines”
http://ftdichip.com/Documents/TechnicalNotes/TN_100_USB_VID-PID_Guidelines.pdf
TN_102, “OEM Technical Support Requirements for FTDI Products
http://ftdichip.com/Documents/TechnicalNotes/TN_102_OEM_Technical_Support_Requirements_for_FTDI
_Products.pdf
TN_104, “Guide to Debugging Customers Failed Driver Installation”
http://www.ftdichip.com/Documents/TechnicalNotes/TN_104_Guide%20to%20Debugging_Customers_Fa
iled_Driver_%20Installation_%20on_%20Windows.pdf
",.-" FTDI xi“. Chlp
Copyright © 2011 Future Technology Devices International Limited 32
Document No.: FT_000329
FT232BL/BQ USB UART IC Datasheet Version 2.2
Clearance No.: FTDI# 171
Appendix B List of Figures and Tables
List of Figures
Figure 2.1 FT232B Block Diagram .............................................................................................. 3
Figure 3.1 QFN-32 Package Pin Out and schematic symbol ....................................................... 6
Figure 3.2 QFN-32 Package Pin Out and schematic symbol ....................................................... 7
Figure 6.1 Bus Powered Configuration ..................................................................................... 17
Figure 6.2 Self Powered Configuration .................................................................................... 18
Figure 6.3 Bus Powered Circuit with 3.3V logic drive / supply voltage .................................... 19
Figure 6.4 Self Powered Circuit with 3.3V logic drive / supply ................................................ 20
Figure 6.5 Bus Powered with Power Switching Configuration .................................................. 21
Figure 7.1 3 Pin Ceramic Resonator Configuration
Figure 7.2 Crystal or 2 Pin Ceramic Resonator Configuration .................................................. 22
Figure 7.3 EEPROM Configuration ............................................................................................ 23
Figure 8.1 USB-RS232 Converter Configuration ....................................................................... 24
Figure 8.2 USB-RS422 Converter Configuration ....................................................................... 25
Figure 8.3 USB-RS485 Converter Configuration ....................................................................... 26
Figure 9.1 Dual LED Configuration
Figure 9.2 Single LED Configuration ........................................................................................ 27
Figure 10.1 32 LQFP Package Dimensions ............................................................................... 28
Figure 10.2 32 LQFP Package Dimensions ............................................................................... 29
List of Tables
Table 1.1 Part Numbers ............................................................................................................. 2
Table 3.1 USB Interface Group................................................................................................... 8
Table 3.2 Power and Ground Group ........................................................................................... 8
Table 3.3 Miscellaneous Signal Group ........................................................................................ 8
Table 3.4 UART Interface Group ................................................................................................ 9
Table 3.5 EEPROM Interface Group ............................................................................................ 9
Table 3.6 Power Control Group .................................................................................................. 9
Table 5.1 Absolute Maximum Ratings ...................................................................................... 14
Table 5.2 Operating Voltage and Current ................................................................................. 15
Table 5.3 UART IO Pin Characteristics (VCCIO = +5.0V) ......................................................... 15
Table 5.4 UART IO Pin Characteristics (VCCIO = +3.0 to +3.6V) ............................................. 15
Table 5.5 XTIN / XTOUT Pin Characteristics ............................................................................. 16
Table 5.6 RESET#, TEST, EECS, EESK, EEDATA Pin Characteristics ............................................ 16
Table 5.7 RSTOUT Pin Characteristics (VCCIO = +1.8V, Standard Drive Level) ........................ 16
Table 5.8 USB I/O Pin Characteristics ..................................................................................... 16
",.-" FTDI xi“. Chlp
Copyright © 2011 Future Technology Devices International Limited 33
Document No.: FT_000329
FT232BL/BQ USB UART IC Datasheet Version 2.2
Clearance No.: FTDI# 171
Appendix C Revision History
Version 1.0 Initial document created 30 April 2002.
Version 1.1 Section 3.2 RESET# Pin description corrected 04 August 2002
(RESET# does not have an internal 200k pull-up to
VCC as previously stated).
Section 3.1, figure 2 pin-out corrected (EECS = Pin 32).
Version 1.2 Pin and package naming made consistent throughout data sheet. 27 October 2003
Section 1.1 Updated to reflect availability of Mac OS X driver.
Section 4.1 Minor corrections.
Section 4.2 Minor changes to functional block descriptions of SIE,
RESET Generator, and EEPROM interface.
Section 3.2 Note added to EEPROM interface group.
Section 3.2 RSTOUT# Pin description amended.
Section 5.2 Minimum operating supply voltage adjusted.
Section 5.2 EESK added to Note 3.
Section 5.2 UART IO pin characteristics amended.
Section 5.2 RESET#, TEST, EECS, EESK, and EEDATA pin
characteristics amended.
Section 5.2 RSTOUT pin characteristics amended.
Section 7.1 Updated recommended ceramic resonator part number
and circuit configuration.
Section 6.2 “USB Self Powered Configuration (1)”
(original figure 8 removed). Recommended circuit for USB self
Powered designs updated. Subsequent figure numbers have
changed as a result.
Section 6.3.1 Note added to description of Bus powered circuit with
3.3V logic drive / supply voltage.
Section 7.6 Self Powered Circuit with 3.3V logic drive / supply
voltage added (new figure 16).
Version 1.3 Section 10 Package drawing amended 10 December 2003
Section 5.1 Floor Life / Relative Humidity specification
added. ESD and Latch Up specifications amended.
Section 7.1 Required resonators / crystal accuracy corrected.
Version 1.4 Grammar Corrections 10 February 2004
Section 11 FTDI Address Updated
Section 4.1 Extended EEPROM Support corrected
Section 3.2 VCCIO Pin description amended.
Section 8.3 RS485 Example Sipex SP481 part number corrected.
Version 1.5 Section 3.2 EESK Pin Description amended. April 2004
Section 6.3.1 Figure 16 PWRCTL Pin number corrected.
Section 6.4 Figure 15 PWREN# Pin number corrected.
Version 1.6 Section 1.1 WinCE drivers now available. November 2004
Section 10 Date code format updated.
Section 5.1 Absolute Maximum Ratings table reformatted.
Version 1.7 Section 1.1 D2XX drivers for Linux and Windows CE now available February 2005
Section 10 FT232BL (lead Free) and FT232BQ
(lead free QFN package) now available.
Version 1.8 Section 1.1 Driver OS Support updated. December 2005
Section 5.1 USB Data line absolute maximum rating added.
Version 1.9 Reformatted and make one datasheet for two Ics 9th August 2010
(FT232BL and FT232BQ)
Updated to remove references to isochronous support
Edited contact details
Added Window 7 and Vista support
",.-" FTDI xi“. Chlp
Copyright © 2011 Future Technology Devices International Limited 34
Document No.: FT_000329
FT232BL/BQ USB UART IC Datasheet Version 2.2
Clearance No.: FTDI# 171
Version 2.0 Edited title, FT232BQ/BL photo, section in 3.1 and sction1.2 15th Sept 2010
Version 2.1 Edited Section 6, circuit diagrams, Figure 6.1 and 6.2. 19th Jan 2011
Corrected BQ reel quantity from 1,000 to 2,500
Version 2.2 Corrected Minimum Input Switching Threshold Voltage 07th Nov 2011
(table 5.3)

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