SX9500 Datasheet by Semtech Corporation

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1
SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
G
ENERAL
D
ESCRIPTION
The SX9500 is a low-cost, very low power 4-channel
capacitive controller that can operate either as a proximity or
button sensor. The SX9500 includes sophisticated on-chip
auto-calibration circuitry to regularly perform sensitivity
adjustments, maintaining peak performance over a wide
variation of temperature, humidity and noise environments,
providing simplified product development and enhanced
performance.
The SX9500 operates directly from an input supply voltage of
2.7 to 5.5V, and includes a separate I2C serial bus supply
input to enable communication with 1.8 5.5V hosts. The
I2C serial communication bus reports proximity or touch
detection and is used to facilitate parameter settings
adjustment. Upon a proximity detection, the NIRQ output
asserts, enabling the user to either determine the relative
proximity distance, or simply obtain an indication of
detection.
A dedicated transmit enable (TXEN) pin is available to
synchronize capacitive measurements for applications that
require synchronous detection, enabling very low supply
current and high noise immunity by only measuring proximity
when requested.
K
EY
P
RODUCT
F
EATURES
2.7 – 5.5V Input Supply Voltage
Capacitive Sensor Inputs
Down to 0.08 fF Capacitance Resolution
Stable Proximity & Touch Sensing With Temperature
Capacitance Offset Compensation to 30pF
Active Sensor Guarding
Automatic Calibration
Ultra Low Power Consumption:
Active Mode: 170 uA
Doze Mode: 18 uA
Sleep Mode: 2.5 uA
400KHz I2C Serial Interface
Four programmable I2C Sub-Addresses
Input Levels Compatible with 1.8V Host Processors
Open Drain NIRQ Interrupt pin
Three (3) Reset Sources: POR, NRST pin, Soft Reset
-40°C to +85°C Operation
Compact Size: 3 x 3mm Thin QFN package
Pb & Halogen Free, RoHS/WEEE compliant
A
PPLICATIONS
Notebooks
Tablets
Mobile Appliances
O
RDERING
I
NFORMATION
Part Number Package
Marking
SX9500IULTRT
1
QFN-20 ZND8
SX9500EVKA Eval. Kit
1
3000 Units/reel
T
YPICAL
A
PPLICATION CIRCUIT
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
Table of Contents
G
ENERAL
D
ESCRIPTION
........................................................................................................................ 1
K
EY
P
RODUCT
F
EATURES
..................................................................................................................... 1
A
PPLICATIONS
....................................................................................................................................... 1
O
RDERING
I
NFORMATION
...................................................................................................................... 1
T
YPICAL
A
PPLICATION CIRCUIT
............................................................................................................ 1
1 G
ENERAL
D
ESCRIPTION
............................................................................................................... 4
1.1
Pin Diagram 4
1.2
Marking Information 4
1.3
Pin Description 5
1.4
Acronyms 5
2 E
LECTRICAL
C
HARACTERISTICS
................................................................................................. 6
2.1
Absolute Maximum Ratings 6
2.2
Operating Conditions 6
2.3
Thermal Characteristics 6
2.4
Electrical Specifications 7
3 P
ROXIMITY
S
ENSING
I
NTERFACE
................................................................................................. 9
3.1
Introduction 9
3.2
Scan Period 9
3.3
Analog Front-End (AFE) 10
3.3.1
Capacitive Sensing Basics 10
3.3.2
AFE Block Diagram 12
3.3.3
Capacitance-to-Voltage Conversion (C-to-V) 12
3.3.4
Shield Control 12
3.3.5
Offset Compensation 12
3.3.6
Analog-to-Digital Conversion (ADC) 13
3.4
Digital Processing 13
3.4.1
Overview 13
3.4.2
PROXRAW Update 15
3.4.3
PROXUSEFUL Update 15
3.4.4
PROXAVG Update 16
3.4.5
PROXDIFF Update 18
3.4.6
PROXSTAT Update 18
3.5
Host Operation 19
3.6
Operational Modes 20
3.6.1
Active 20
3.6.2
Doze 20
3.6.3
Sleep 20
3.6.4
TXEN Pin 20
4 I2C
INTERFACE
........................................................................................................................... 21
4.1
Introduction 21
4.2
I2C Write 21
4.3
I2C Read 21
5 R
ESET
......................................................................................................................................... 23
5.1
Power-up 23
5.2
NRST Pin 23
5.3
Software Reset 24
6 I
NTERRUPT
................................................................................................................................. 25
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
6.1
Power-up 25
6.2
Assertion and Clearing 25
7 P
INS DESCRIPTION
..................................................................................................................... 26
7.1
V
DD
and SV
DD
26
7.2
TXEN 26
7.3
Capacitive Sensing Interface (CS0, CS1, CS2, CS3, CSG) 26
7.4
Host Interface 26
7.4.1
NIRQ 26
7.4.2
SCL, NRST and TXEN 27
7.4.3
SDA 27
8 R
EGISTERS
................................................................................................................................. 28
8.1
Overview 28
8.2
Detailed Description 29
9 A
PPLICATION
I
NFORMATION
...................................................................................................... 33
9.1
Typical Application Circuit 33
9.2
External Components Recommended Values 33
10 P
ACKAGING
I
NFORMATION
........................................................................................................ 34
10.1
Outline Drawing 34
10.2
Land Pattern 35
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
1 G
ENERAL
D
ESCRIPTION
1.1 Pin Diagram
Figure 1: Pin Diagram
1.2 Marking Information
ZND8
yyww
xxxx
yyww= Date Code
xxxx = Lot Number
Figure 2: Marking Information
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
1.3 Pin Description
Number
Name Type Description
1 CSG Analog Capacitive Sensor Guard/Shield
2 CS3 Analog Capacitive Sensor 3
3 CS2 Analog Capacitive Sensor 2
4 CS1 Analog Capacitive Sensor 1
5 CS0 Analog Capacitive Sensor 0
6 GND Ground Ground
7 NC Not Used Do Not Connect
8 NC Not Used
No
t
Connect
9 NC Not Used
No
t
Connect
10 NC Not Used
No
t
Connect
11 V
DD
Power Core power supply
12 SV
DD
Power
Host interface power supply
.
Must be V
DD
at all times (including during power-up and power-down)
13 NIRQ Digital Output Interrupt request, active LOW, requires pull-up resistor to SV
DD
14 SCL Digital Input I2C Clock, requires pull-up resistor to SV
DD
15 SDA Digital I/O I2C Data, requires pull-up resistor to SV
DD
16 TXEN Digital Input Transmit Enable, active HIGH (Tie to SV
DD
if not used).
17 NRST
Digital
Input
Input
External reset, active LOW (Tie to SV
DD
if not used).
18 A1 Digital Input I2C Sub-Address, connect to GND or V
DD
19 A0 Digital Input I2C Sub-Address, connect to GND or V
DD
20 GND Ground Ground
DAP GND Ground Exposed Pad. Connect to Ground
Table 1: Pin Description
1.4 Acronyms
DAP Die Attach Paddle
RF Radio Frequency
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
2 E
LECTRICAL
C
HARACTERISTICS
2.1 Absolute Maximum Ratings
Stresses above the values listed in Absolute Maximum Ratings” may cause permanent damage to the device.
This is a stress rating only and functional operation of the device at these, or any other conditions beyond the
“Operating Conditions”, is not implied. Exposure to Absolute Maximum Rating conditions for extended periods
may affect device reliability and proper functionality.
Parameter Symbol Min Max Unit
Supply Voltage V
DD
-0.5 6.0
V SV
DD
-0.5 6.0
Input Voltage (non-supply pins) V
IN
-0.5 V
DD
+0.3
Input Current (non-supply pins) I
IN
-10 10 mA
Operating Junction Temperature T
JCT
-40 125
°C Reflow Temperature T
RE
- 260
Storage Temperature T
STOR
-50 150
ESD HBM (Human Body model, to JESD22-A114) ESD
HBM
8 - kV
Table 2: Absolute Maximum Ratings
2.2 Operating Conditions
Parameter Symbol Min Max Unit
Supply Voltage V
DD
2.7 5.5 V
SV
DD
1.65 V
DD
Ambient Temperature T
A
-40 85 °C
Table 3: Operating Conditions
Note: During power-up or power-down, SVDD must be less than or equal to VDD
2.3 Thermal Characteristics
Parameter
Symbol
Typical
Unit
Thermal Resistance – Junction to Air
(Static Airflow)
θ
JA
34
°C/W
Table 4: Thermal Characteristics
Note:
θ
JA
is calculated from a package in still air, mounted to 3" x 4.5", 4-layer FR4 PCB with thermal vias under
exposed pad per JESD51 standards.
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
2.4 Electrical Specifications
All values are valid within the operating conditions unless otherwise specified.
Typical values are given for T
A
= +25°C, VDD=SVDD=3.3V unless otherwise specified.
Parameter Symbol Conditions Min Typ Max Unit
Current Consumption
Sleep
(no sensor enabled) I
SLEEP
Power down, all analog circuits shut
down. (I2C listening)
- 2.5 -
uA
Doze
(all sensors enabled) I
DOZE
SCAN
PERIO
D =
2
00
m
s
DOZEPERIOD = 2xSCANPERIOD
FREQ = 167kHz
RESOLUTION = Medium
VDD = 5V
- 18 -
Active
(all sensors enabled) I
ACTIVE
SCANPERIOD
= 30m
s
FREQ = 167kHz
RESOLUTION = Medium
VDD = 5V
- 170 -
Outputs: SDA, NIRQ
Output Cur
rent at Output Low
Voltage I
OL
VOL = 0.4V 6 - - mA
Maximum Output LOW Voltage V
OL
(Max) SV
DD
> 2V - - 0.4 V
SV
DD
2V - - 0.2 x SV
DD
Inputs: SCL, SDA, TXEN
Input logic high V
IH
0.8 x SV
DD
- SV
DD
+ 0.3 V
Input logic low V
IL
-0.3 - 0.25 x SVDD
Input leakage current I
L
CMOS input -1 - 1 uA
Hysteresis
V
HYS
SV
DD
> 2V -
0.05x
SV
DD
-
V
SV
DD
2V -
0.1x
SV
DD
-
TXEN Delay TXEN
ACTDLY
Delay
between TXEN rising
edge and SX9500 starting
measurements - 100 - µs
Input
s
:
A0, A1
Input logic high V
IH
0.7 x V
DD
- V
DD
+ 0.3 V
Input logic low V
IL
-0.3 - 0.3 x VDD
Input: NRST
Input logic high V
IH
SV
DD
> 2V 0.7 x SV
DD
- SV
DD
+ 0.3
V
SV
DD
2V 0.75 x SV
DD
-
Input logic low V
IL
SV
DD
> 2V - - 0.6
SV
DD
2V - - 0.3 x SV
DD
NRST minimum pulse width
T
RESETPW
2
-
-
µs
Start-up
Power-up time T
POR
- 1 - ms
Table 5: Electrical Specifications
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
Parameter Symbol Conditions Min Typ Max Unit
I2C Timing Specifications (Cf.
Figure 3
and
Figure 4
below)
SCL clock frequency
f
SCL
-
-
400
k
Hz
SC
L low period
t
LOW
1.3
-
-
us
SCL high period
t
HIGH
0.6
-
-
Data setup time
t
SU;DAT
0.
1
-
-
Data hold time
t
HD;DAT
0
-
-
Repeated start setup time
t
SU;STA
0.6
-
-
Start condition hold time
t
HD;STA
0.6
-
-
Stop condition setup time
t
SU;STO
0.6
-
-
Bus free time between stop and start
t
BUF
1.3
-
-
Input glitch suppression
t
SP
Note 1
-
-
50
n
s
Note 1: Minimum glitch amplitude is 0.7V
DD
at High level and Maximum 0.3V
DD
at Low level.
Table 6: I2C Timing Specifications
Figure 3
: I2C Start and Stop Timing
Figure 4: I2C Data Timing
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
3 P
ROXIMITY
S
ENSING
I
NTERFACE
3.1 Introduction
The purpose of the proximity sensing interface is to detect when a conductive object (usually a body part i.e.
finger, palm, face, etc) is in the proximity of the system. Note that proximity sensing can be done thru the air or
thru a solid (typically plastic) overlay (also called “touch” sensing).
The chip’s proximity sensing interface is based on capacitive sensing technology. An overview is given in figure
below.
Shield
Sensor Analog
Front-End
(AFE)
Digital
Processing
SX9500
PROXSTAT
0 1 0
Finger, palm,
face, lap, etc
CSx
CSG
Figure 5: Proximity Sensing Interface Overview
The sensor can be a simple copper area on a PCB or FPC for example. Its capacitance (to ground) will
vary when a conductive object is moving in its proximity.
The optional shield can be also be a simple copper area on a PCB or FPC below/under/around the
sensor. It is used to protect the sensor against potential surrounding noise sources and improve its
global performance. It also brings directivity to the sensing, for example sensing objects approaching
from top only.
The analog front-end (AFE) performs the raw sensor’s capacitance measurement and converts it into a
digital value. It also controls the shield. See §3.3 for more details.
The digital processing block computes the raw capacitance measurement from the AFE and extracts a
binary information PROXSTAT corresponding to the proximity status, i.e. object is “Far” or “Close”. It also
triggers AFE operations (compensation, etc). See §3.4 for more details.
3.2 Scan Period
To save power and since the proximity event is slow by nature, the chip will be waken-up regularly at every
programmed scan period (SCANPERIOD) to first sense sequentially each of the enabled CSx pins and then
process new proximity samples/info. The chip will be in idle mode most of the time. This is illustrated in figure
below
Figure 6: Proximity Sensing Sequencing
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
The sensing and processing phase’s durations vary with the number of sensors enabled, the sampling
frequency, and the resolution programmed. During the Idle phase, the SX9500‘s analog circuits are turned off.
Upon expiry of the idle timer, a new scan period cycle begins.
The scan period determines the minimum reaction time (actual/final reaction time also depends on debounce and
filtering settings) and can be programmed from 30ms to 400ms.
3.3 Analog Front-End (AFE)
3.3.1 Capacitive Sensing Basics
Capacitive sensing is the art of measuring a small variation of capacitance in a noisy environment. As mentioned
above, the chip’s proximity sensing interface is based on capacitive sensing technology. In order to illustrate
some of the user choices and compromises required when using this technology it is useful to understand its
basic principles.
To illustrate the principle of capacitive sensing we will use the simplest implementation where the sensor is a
copper plate on a PCB.
The figure below shows a cross-section and top view of a typical capacitive sensing implementation. The sensor
connected to the chip is a simple copper area on top layer of the PCB. It is usually surrounded (shielded) by
ground for noise immunity (shield function) but also indirectly couples via the grounds areas of the rest of the
system (PCB ground traces/planes, housing, etc). For obvious reasons (design, isolation, robustness …) the
sensor is stacked behind an overlay which is usually integrated in the housing of the complete system.
PCB dielectric
Ground
Cut view
Top view
PCB copper
Sensor
Overlay
Figure 7: Typical Capacitive Sensing Implementation
When the conductive object to be detected (finger/palm/face, etc) is not present, the sensor only sees an
inherent capacitance value C
Env
created by its electrical field’s interaction with the environment, in particular
with ground areas.
When the conductive object (finger/palm/face, etc) approaches, the electrical field around the sensor will be
modified and the total capacitance seen by the sensor increased by the user capacitance C
User
. This
phenomenon is illustrated in the figure below.
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
Figure 8: Proximity Effect on Electrical Field and Sensor Capacitance
The challenge of capacitive sensing is to detect this relatively small variation of C
Sensor
(C
User
usually contributes
for a few percent only) and differentiate it from environmental noise (C
Env
also slowly varies together with the
environment characteristics like temperature, etc). For this purpose, the chip integrates an auto offset
compensation mechanism which dynamically monitors and removes the C
Env
component to extract and process
C
User
only. See §3.3.5 for more details.
In first order, C
User
can be estimated by the formula below:
A
is the common area between the two electrodes hence the common area between the user’s finger/palm/face
and the sensor.
d
is the distance between the two electrodes hence the proximity distance between the user and the system.
0
ε
is the free space permittivity and is equal to 8.85 10e-12 F/m (constant)
r
ε
is the dielectric relative permittivity.
Typical permittivity of some common materials is given in the table below.
Material Typical
r
ε
Glass
8
FR4
5
Acrylic Glass 3
Wood 2
1
Table 7: Typical Permittivity of Some Common Materials
From the discussions above we can conclude that the most robust and efficient design will be the one that
minimizes C
Env
value and variations while improving C
User
.
d
Aεε
C
r
User
0
=
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
3.3.2 AFE Block Diagram
Figure 9: Analog Front-End Block Diagram
3.3.3 Capacitance-to-Voltage Conversion (C-to-V)
The sensitivity of the interface is defined by RANGE and GAIN parameters.
PROXFREQ defines the operating frequency of the interface and should be set as high as possible for power
consumption reasons.
3.3.4 Shield Control
SHIELDEN allows enabling or disabling the shield function.
3.3.5 Offset Compensation
Offset compensation consists in performing a one-time measurement of C
Env
and subtracting it to the total
capacitance C
Sensor
in order to feed the ADC with the closest contribution of C
User
only.
Figure 10: Offset Compensation Block Diagram
The ADC input C
User
is the total capacitance C
Sensor
to which C
Env
is subtracted.
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
There are five possible compensation sources which are illustrated in the figure below. When set to 1 by any of
these sources, COMPSTAT will only be reset once the compensation is completed.
Figure 11: Compensation Request Sources
Reset: a compensation for all sensors is automatically requested when a reset is performed (power-up,
NRST pin, RegReset)
COMPDONEIRQ (I2C): a compensation for all sensors can be manually requested anytime by the host
through I2C interface by writing a 1 into COMPDONEIRQ.
AVGTHRESH: a compensation for all sensors or only the affected one (depending on COMPMETHOD)
can be automatically requested if it is detected that C
Env
has drifted beyond a predefined range
programmed by the host.
COMPPRD: a compensation can be automatically requested at a predefined rate programmed by the
host.
STUCK: a compensation can be automatically requested if it is detected that the proximity “Close” state
lasts longer than a predefined duration programmed by the host.
Please note that the compensation request flag can be set anytime but the compensation itself is always done at
the beginning of a scan period to keep all parameters coherent.
Also, when compensation occurs, all PROXSTAT flags turn OFF (ie no proximity detected) independently from
the user’s potential actual presence.
3.3.6 Analog-to-Digital Conversion (ADC)
An ADC is used to convert the analog capacitance information into a digital word PROXRAW.
3.4 Digital Processing
3.4.1 Overview
The main purpose of the digital processing block is to convert the raw capacitance information coming from the
AFE (PROXRAW) into a robust and reliable digital flag (PROXSTAT) indicating if something is close to the
proximity sensor.
The offset compensation performed in the AFE is a one-time measurement. However, the environment
capacitance C
Env
may vary with time (temperature, nearby objects, etc). Hence, in order to get the best
estimation of C
User
(PROXDIFF) it is needed to dynamically track and subtract C
Env
variations. This is performed
by filtering PROXUSEFUL to extract its slow variations (PROXAVG).
PROXDIFF is then compared to user programmable threshold (PROXTHRESH) to extract PROXSTAT flag.
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
Figure 12: Digital Processing Block Diagram
Digital processing sequencing is illustrated in figure below. At every scan period wake-up, the block updates
sequentially PROXRAW, PROXUSEFUL, PROXAVG, PROXDIFF and PROXSTAT before going back to Idle
mode.
Figure 13: Digital Processing Sequencing
Digital processing block also updates COMPSTAT (set when compensation is currently pending execution or
completion)
SEMTECH E] a a M $ // \\ Perform Offset Campansamn sum AFE # Wan lur new PROXRAW # Slop AFE ¢ a a u i /// \\\\ .1, <\proxcompsu:> \\ \ /// 1‘” , PROXUSEFUL: F(PROXRA , PROXUSEFUL PROXUSEFULIIH] = PROXRAW ; RAWH LT) L‘—
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
3.4.2 PROXRAW Update
PROXRAW update consists mainly in starting the AFE and waiting for the new PROXRAW values (one for each
CSx/sensor pin) to be ready. If compensation was pending it is performed first.
Figure 14: ProxRaw Update
Note that PROXRAW is not available in the Sensor Data Readback” section of the registers. If needed it can be
observed by setting RAWFILT=00 and reading PROXUSEFUL.
3.4.3 PROXUSEFUL Update
PROXUSEFUL update consists in filtering PROXRAW upfront to remove its potential high frequencies
components(system noise, interferer, etc) and extract only user activity (few Hz max) and slow environment
changes.
Figure 15: PROXUSEFUL Update
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
3.4.4 PROXAVG Update
PROXAVG update consists in averaging PROXUSEFUL to ignore its “fast” variations (i.e. user finger/palm/hand)
and extract only the very slow variations of environment capacitance C
Env
.
One can program a debounced threshold (AVGTHRESH/AVGDEB) to define a range within which PROXAVG
can vary without triggering compensation (i.e. small acceptable environment drift).
Large positive values of PROXUSEFUL are considered as normal (user finger/hand/head) but large negative
values are considered abnormal and should be compensated quickly. For this purpose, the averaging filter
coefficient can be set independently for positive and negative variations via AVGPOSFILT and AVGNEGFILT.
Typically we have AVGPOSFILT > AVGNEGFILT to filter out (abnormal) negative events faster.
To prevent PROXAVG to be “corrupted” by user activity (should only reflect environmental changes) it is frozen
when proximity is detected.
Figure 16: ProxAvg vs Proximity Event
a SEMTECH — { /// \ / \\ COMPSTAT \ //% PROXAVG = PROXRAW Un-lreeze V COMPSTAT : ‘0 Jr PROXAVG lrazem PROXAVG : FROXAVG : F(PROXUSEFUL‘ F(PROXUSEFUL. FROXAqu], FROXAqu], AVGNEGFI LT) AVGPOSF‘ LT) >= AVGTHRESH or <= vavgthresh="" proxavg="" c‘earbolh="" debuunoe="" ooumers="" n0="" avgdeb="" \="" \="" canmuon="" reacheaz,="" yes="" v="" $="" update="" we="" cone?”="" counter="" '="" clear="" denounce="" counter="">
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
Figure 17: ProxAvg Update
a SEMTECH — 3.4.5 l PROXD/FF [PROXUSEFUL e PROXA VG] >> 4 l ROXTHRESH . HYS/I/ Yes Yes Clear Far Clear hclh Clear Close flebaurtoe flebaurtoe flebnunoe counter counters counter No CLOSEDEB FARDEB mndtltan rezcnem mndtltan rezcnem * es iYes u d IVCI u ale F p z 2 use p 3 gr ”0537” menounce flebaunoe PROS?“ caunler caunler Freeze Un-lreeze PROXAVG PROXAVG Clear Close Clear Far flebnunoe flebnunoe counter counter
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3.4.5 PROXDIFF Update
PROXDIFF update consists in the complementary operation i.e. subtracting PROXAVG to PROXUSEFUL to
ignore slow capacitances variations (C
Env
) and extract only the user related variations i.e. C
User
.
Figure 18: ProxDiff Update
Note that only the 12 upper bits of [PROXUSEFUL – PROXAVG] are kept for PROXDIFF.
3.4.6 PROXSTAT Update
PROXSTAT update consists in taking PROXDIFF information (C
User
), comparing it with a user programmable
threshold PROXTHRESH and finally updating PROXSTAT accordingly. When PROXSTAT=1, PROXAVG is
frozen to prevent the user proximity signal averaging and hence absorbed into C
Env
.
Figure 19: PROXSTAT Update
a SEMTECH Usev. in Usav out at vange - e - - V-_ - '- - - m D T T ' T T i T T NI R0 |_J |—| T20 Read Reglqum f T |:| ldTe - PVOXTmle Sensing (Analog + DTgnau Usev. in User out m was NIRQ L_J L_J |_T T_| LJ T20 Read T T T T T |:| We I
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Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
3.5 Host Operation
An interrupt can be triggered when the user is detected to be close (in range), detected to be far (out of range),
or both (CLOSEIRQEN, FARIRQEN).
Figure 20: Proximity Sensing Host Operation (RegIrqMsk[6:3] = 1100)
An interrupt can also be triggered at the end of each proximity sensing operation, indicating to the host when the
proximity sensing block is running (CONVDONEIRQEN). This may be used by the host to synchronize noisy
system operations or to read sensor data (PROXUSEFUL, PROXAVG, PROXDIFF) synchronously for
monitoring purposes.
Figure 21: Proximity Sensing Host Operation (RegIrqMsk[6:3] = 0001)
In both cases above, an interrupt can also be triggered at the end of compensation (COMPDONEIRQEN).
Idle
NIRQ
I2C Read
Proxi
mity Sensing (Analog + Digital)
PROXSTAT
SCANPERIOD
tick
User in
User out of range
Idle
NIRQ
I2C Read
RegIrqSrc
Proximity Sensing (Analog + Digital)
PROXSTAT
SCANPERIOD
tick
User in
User out of range
SEMTECH E] a as a as N a as (a a as a
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
3.6 Operational Modes
3.6.1 Active
Active mode has the shortest scan periods, typically 30ms. In this mode, all enabled sensors are scanned and
information data is processed within this interval. The Active scan period is user configurable (SCANPERIOD)
and can be extended up to 400ms.
3.6.2 Doze
In some applications, the reaction/sensing time needs to be fast when the user is present (proximity detected),
but can be slow when not detection has been done for some time.
The Doze mode, when enabled (DOZEEN), allows the chip to automatically switch between a fast scan period
(SCANPERIOD) during proximity detection and a slow scan period (DOZEPERIOD) when no proximity is being
detected (up to 6.4s). This allows reaching low average power consumption values at the expense obviously of
longer reaction times.
As soon as proximity is detected on any sensor, the chip will automatically switch to Active mode while when it
has not detected an object for DOZEPERIOD, it will automatically switch to Doze mode.
3.6.3 Sleep
Sleep mode can be entered by disabling all sensors (SENSOREN=0000). It places the SX9500 in its lowest
power mode, with sensor scanning completely disabled and idle period set to continuous. In this mode, only the
I2C serial bus is active. Enabling any sensor will make the chip leave Sleep mode (for Doze if enabled, else
Active mode)
3.6.4 TXEN Pin
The TXEN input enables proximity sensing when HIGH, likewise when the TXEN input is LOW, the SX9500 is in
Sleep mode. Specifically, on the rising edge of TXEN the SX9500 will begin measuring the sensors normally at
the programmed rate (SCANPERIOD, DOZEPERIOD) as long as TXEN remains HIGH. When TXEN goes LOW
the current measurement sequence will complete and then measurement will cease until the next rising edge of
TXEN.
This feature can be used to synchronize proximity sensing with noisy and/or RF activity for example.
SEMTECH ‘S‘SA‘0‘A‘RA‘A‘WDO‘A‘WD1‘A‘...‘WDn‘A‘P‘ H—JH—J S: Start conditlon optional optional SA: Slave Address A; Acknowledge RA“- Register Address |:| from master to slave WDn: Write Data byte (0...n) P: Skop condition |:| from slave to masker
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
4 I2C
INTERFACE
4.1 Introduction
The I2C implemented on the SX9500 and used by the host to interact with it is compliant with:
- Standard (100kb/s) and fast mode (400kb/s)
- Slave mode
- 7-bit address (default is 0x28 assuming A1=A0=0)
The SX9500 has two I/O pins (A0 and A1) that provides four possible, user selectable I2C addresses:
Table 8: I2C Sub-Address Selection
The host can use the I2C to read and write data at any time, and these changes are effective immediately.
Therefore the user should ideally disable the sensor before changing settings, or discard the results while
changing.
4.2 I2C Write
The format of the I2C write is given in Figure 12. After the start condition [S], the slave address (SA) is sent,
followed by an eighth bit (‘0’) indicating a Write. The SX9500 then Acknowledges [A] that it is being addressed,
and the Master sends an 8 bit Data Byte consisting of the SX9500 Register Address (RA). The Slave
Acknowledges [A] and the master sends the appropriate 8 bit Data Byte (WD0). Again the Slave Acknowledges
[A]. In case the master needs to write more data, a succeeding 8 bit Data Byte will follow (WD1), acknowledged
by the slave [A]. This sequence will be repeated until the master terminates the transfer with the Stop condition
[P].
Figure 22: I2C Write
The register address is incremented automatically when successive register data (WD1...WDn) is supplied by the
master.
4.3 I2C Read
The format of the I2C read is given in Figure 13. After the start condition [S], the slave address (SA) is sent,
followed by an eighth bit (‘0’) indicating a Write. The SX9500 then Acknowledges [A] that it is being addressed,
and the Master responds with an 8-bit Data consisting of the Register Address (RA). The Slave Acknowledges
[A] and the master sends the Repeated Start Condition [Sr]. Once again, the slave address (SA) is sent,
followed by an eighth bit (‘1’) indicating a Read. The SX9500 responds with an Acknowledge [A] and the read
A1 A0 Address
0 0 0x28
0 1 0x29
1 0 0x2A
1 1 0x2B
a SEMTECH — lslSAlolAlRAlAlSrlSAl1lAlRDolAlRD1 AlRDnlNlPl S: SR S r: A: N: RA: RDn: P: Start condition W H_J Slave Address . . Repeated Start condition optional optional Acknowledge Not Acknowledge (terminating read stream) |:| [70m master to slave Register Address Read Data byte (0...n) |:| from slave to master Stop condition
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Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
Data byte (RD0). If the master needs to read more data it will acknowledge [A] and the SX9500 will send the
next read byte (RD1). This sequence can be repeated until the master terminates with a NACK [N] followed by a
stop [P].
Figure 23: I2C Read
The register address is incremented automatically when successive register data (RD1...RDn) is retrieved by the
master.
a SEMTECH +V Time NIRQ Time ngn N RST THE: Ready \ \ ‘ swam \ \ Hosl reads Reglmsm and dears me Inlermpl
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Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
5 R
ESET
5.1 Power-up
During a power-up condition, the NIRQ output is HIGH until V
DD
has met the minimum input voltage requirements
and a T
POR
time has expired upon which, NIRQ asserts to a LOW condition indicating the SX9500 is initialized.
The host must perform an I2C read of RegIrqSrc to clear this NIRQ status. The SX9500 is then ready for normal
I2C communication and is operational.
Figure 24: Power-up vs. NIRQ
5.2 NRST Pin
When the host asserts NRST LOW (for min. T
RESETPW
) and then HIGH, the SX9500 will reset its internal registers
and will become active after T
POR
. When not used, this pin must be pulled high to SV
DD
.
Figure 25: Hardware Reset
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
5.3 Software Reset
The host can also perform a reset anytime by writing 0xDE into RegReset. The NIRQ output will be asserted
LOW and the Host is required to perform an I2C read to clear this NIRQ status.
NIRQ
SX9500
Ready
High
HOST issues a soft Reset
HOST clears
the Interrupt
Low
Figure 26: Software Reset
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
6 I
NTERRUPT
Except RESETIRQ, all interrupt sources are disabled by default upon power-up and resets, and thus must be
enabled by the host. Any or all of the following interrupts can be enabled by writing a “1” into the appropriate
locations within the RegIrqMsk register:
Close (proximity detected)
Far (proximity un-detected)
Compensation completed
Conversion completed
The interrupt status can be read from RegIrqSrc for each of these interrupt sources.
6.1 Power-up
During initial power-up, the NIRQ output is HIGH. Once the SX9500 internal power-up sequence has completed,
NIRQ is asserted LOW, signaling that the SX9500 is ready. The host must perform a read to RegIrqSrc to
acknowledge and the SX9500 will clear the interrupt and release the NIRQ line.
6.2 Assertion and Clearing
The NIRQ can be asserted in either the Active or Doze mode during a scan period. The NIRQ will be
automatically cleared after the host performs a read of RegIrqSrc (which content will be cleared as well).
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SX9500
Ultra Low Power, Four Channels
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7 P
INS DESCRIPTION
7.1 V
DD
and SV
DD
These are the device supply voltages. V
DD
is the supply voltage for the internal core. SV
DD
is the supply
voltage for the host interface. NOTE: SV
DD
MUST be equal or lower than V
DD
at all times.
7.2 TXEN
This signal can be used in many applications if a conversion trigger/enable is needed. This input pin
synchronizes the Capacitance Sensing inputs in systems that need to (for example) transmit RF signals. When
this signal is active, SX9500 performs capacitive measurements. If this input becomes inactive during the middle
of a measurement, the SX9500 will complete all remaining measurements and will enter sleep mode until TXEN
goes active again.
7.3 Capacitive Sensing Interface (CS0, CS1, CS2, CS3, CSG)
The Capacitance Sensing input pins CS0, CS1, CS2 and CS3 are connected directly to the Capacitance Sensing
Interface circuitry which converts the sensed capacitance into digital values. The Capacitive Sensor Guard
(CSG) output provides a guard reference to minimize the parasitic sensor pin capacitances to ground.
Capacitance sensor pins which are not used must not be connected. Additionally, CSx pins must be connected
directly to the capacitive sensors using a minimum length circuit trace to minimize external “noise” pick-up.
The capacitance sensor and capacitive sensor guard pins are protected from ESD events to VDD and GROUND.
7.4 Host Interface
The Host Interface consists of: NIRQ, NRST, SCL, SDA, and TXEN. These signals are discussed below.
7.4.1 NIRQ
The NIRQ pin is an open drain output that requires an external pull-up resistor (1...10 kOhm). The NIRQ pin is
protected from ESD events to VDD and GROUND.
Figure 27: NIRQ Output Simplified Diagram
SVDD
R_
INT
NIRQ
SX9500
INT
NIRQ to Host
VDD
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Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
7.4.2 SCL, NRST and TXEN
The SCL, NRST and TXEN pins are high impedance input pins that require an external pull-up resistor (1..10
kOhm). NRST and TXEN can be connected without the requirement for a pull-up resistor if driven from a push-
pull host output. These pins are protected from ESD events to VDD and GROUND.
Figure 28: SCL/TXEN/NRST
7.4.3 SDA
SDA is an I/O pin that requires an external pull-up resistor (1…10 kOhm). The SDA I/O pin is protected to VDD
and GROUND.
Figure 29: SDA Simplified Diagram
SVDD
R_
SDA
SDA
SDA_OUT
To/From Host
SDA_IN
VDD
SVDD
R
S
CL/TXEN/NRST
From
Host
SCL_IN/TXEN
_IN/NRST_IN
VDD
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Ultra Low Power, Four Channels
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8 R
EGISTERS
8.1 Overview
The SX9500 allows the user full parameter customization for sensor sensitivity, hysteresis, detection thresholds,
etc. Custom parameters are controlled thru the volatile registers below and must be uploaded by the host thru
I2C after power-up or after a reset.
Address
Name
Default
Description
0x00
RegIrqSrc
0x80
Interrupt & Status 0x01 RegStat 0x0F
0x03 RegIrqMsk 0x00
0x06 RegProxCtrl0 0x0F
Proximity Sensing Control
0x07
RegProx
Ctrl1
0x40
0x08
RegProx
Ctrl2
0x08
0x09 RegProxCtrl3 0x40
0x0A RegProxCtrl4 0x00
0x0B RegProxCtrl5 0x00
0x0C RegProxCtrl6 0x00
0x0D
RegProx
Ctrl7
0x00
0x0E
RegProx
Ctrl8
0x00
0x
2
0
RegSensorSel
0x00
Sensor Data Readback
0x21 RegUseMsb 0x00
0x22 RegUseLsb 0x00
0x23 RegAvgMsb 0x00
0x2
4
Reg
AvgL
sb
0x00
0x2
5
RegDiff
M
sb
0x00
0x2
6
RegDiff
L
sb
0x00
0x27 RegOffsetMsb 0x00
0x28 RegOffsetLsb 0x00
0x7F RegReset 0x00 Software Reset
Table 9: Registers Overview
NOTES:
1) Addresses not listed above are reserved and should not be written.
2) Reserved bits should be left to their default value unless otherwise specified.
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Ultra Low Power, Four Channels
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8.2 Detailed Description
Addr.
Name
R/W
Bits
Variable
Default
Function
Interrupt
&
Status
0x00
RegIrqSrc
R
7
RESETIRQ
1
Reset interrupt source status. (i.e.
reset occurred)
6 CLOSEIRQ 0 Close interrupt source status. (i.e.
PROXSTATx rising edge)
5
FARIRQ
0
Far interrupt source status. (i.e.
PROXSTATx falling edge)
R/W
4 COMPDONEIRQ 0 Compensation interrupt source
status. (i.e. compensation occurred)
When set to 1, triggers
compensation
R 3 CONVDONEIRQ 0 Conversion interrupt source status.
(i.e. new set of sensor data
available)
2:1 Reserved 00
0 TXENSTAT 0 Indicates current TXEN pin status.
0x01 RegStat R 7 PROXSTAT3 0 Indicates if proximity is being
detected for CS3
(i.e. sensor’s PROXDIFF value is
above detection threshold)
6
PROX
STAT
2
0
Indicates if proximity is being
detected for CS2
(i.e. sensor’s PROXDIFF value is
above detection threshold)
5
PROXSTAT
1
0
Indicates if proximity is being
detected for CS1
(i.e. sensor’s PROXDIFF value is
above detection threshold)
4 PROXSTAT0 0 Indicates if proximity is being
detected for CS0
(i.e. sensor’s PROXDIFF value is
above detection threshold)
3:0 COMPSTAT 1111 Indicates which capacitive sensor(s)
has a compensation pending.
[3:0] = [CS3, CS2, CS1, CS0]
0x03 RegIrqMsk R 7 Reserved 0
R/W
6 CLOSEIRQEN 0 Enables the close interrupt.
5 FARIRQEN 0 Enables the far interrupt.
4 COMPDONEIRQEN 0 Enables the compensation interrupt.
3 CONVDONEIRQEN 0 Enables the conversion interrupt.
R 2:0 Reserved 000
Proximity
Sensing C
ontrol
0x06
Reg
Prox
Ctrl0
R/W
7
Reserved
0
SCAN
PERIOD
000
Defines
the
Active
scan
period :
000: 30 ms (Typ.)
001: 60 ms
010: 90 ms
011: 120 ms
100: 150 ms
101: 200 ms
110: 300 ms
111: 400 ms
Low values will allow fast reaction
time while high values will provide
low power consumption.
SENSOREN
1111
Enable
s sensor pins.
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Ultra Low Power, Four Channels
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[3:0] = [CS3, CS2, CS1, CS0]
0x07 RegProxCtrl1 R/W
7:6 SHIELDEN 01 Enables shield function on CSG pin:
00: Off, high impedance.
01: On (Typ.)
1x: Reserved
R/W
Reserved
0000
R/W
RANGE
00
Defines the input capacitance range:
00: Large (typ. +/-7.3pF FS)
01: Medium Large (typ. +/-3.7pF FS)
10: Medium Small (typ. +/-3pF FS)
11: Small (typ. +/-2.5pF FS)
This parameter can be seen as an
analog gain (small range = high
gain)
Full scale (FS) values assume no
digital gain.
0x08
RegProx
Ctrl2
R/W
7
Reserved
0
6:5 GAIN 00 Defines the digital gain factor:
00: Off (x1)
01: x2
10: x4
11: x8 (Typ.)
This is a pure digital gain (value
shift) applied at the ADC output.
FREQ
0
1
Defines
the
sampling
frequency
:
00: 83 kHz
01: 125 kHz
10: 167 kHz (Typ.)
11: Reserved
RESOLUTION
000
Defines
the
capacitance
measurement resolution/precision:
000: Coarsest
….
100: Medium
….
111: Finest (Typ.)
0x09 RegProxCtrl3 R/W
7 Reserved 0
6 DOZEEN 1 Enables Doze mode.
5:4 DOZEPERIOD 00 When DOZEN=1, defines the Doze
scan period:
00: 2x SCAN
PERIOD
01: 4x SCANPERIOD
10: 8x SCANPERIOD
11: 16x SCANPERIOD
3:2 Reserved 00
1:0 RAWFILT 00 Defines PROXRAW filter strength :
00: Off - No filtering
01: Low (Typ.)
10: Medium
11: High - Max filtering
0x0A RegProxCtrl4 R/W
7:0 AVGTHRESH
0x00 Defines the positive and negative
average thresholds which will trigger
compensation:
Thresholds = +/- 128x AVGTHRESH
Typically set between +/-16384 and
+/-24576 (i.e. ½ to ¾ of the system
dynamic range).
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SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
Should not be set below 0x40.
0x0B RegProxCtrl5 R/W
7:6 AVGDEB
00 Defines the average debouncer
applied to AVGTHRESH:
00: Off
01: 2 samples
10: 4 samples
11: 8 samples
5:3 AVGNEGFILT 000 Defines the average negative filter
strength:
000: Off - No filtering
001: Lowest (Typ.)
….
111: Highest - Max filtering
2:0 AVGPOSFILT 000 Defines the average positive filter
strength:
000: Off - No filtering
001: Lowest
….
111: Highest - Max filtering (Typ.)
0x0C RegProxCtrl6 R/W
7:5 Reserved 000
4:0 PROXTHRESH 00000 Defines the proximity detection
threshold (for all sensors).
00000: 0
00001: 20
00010: 40
00011: 60
00100: 80
00101: 100
00110: 120
00111: 140
01000: 160
01001: 180
01010: 200
01011: 220
01100: 240
01101: 260
01110: 280
01111: 300
10000: 350
10001: 400
10010: 450
10011: 500
10100: 600
10101: 700
10110: 800
10111: 900
11000: 1000
11001: 1100
11010: 1200
11011: 1300
11100: 1400
11101: 1500
11110: 1600
11111: 1700
Low values allow good
sensitivity/distance while higher
values allow better noise immunity.
0x0D
Reg
Prox
Ctrl7
R/W
7
AVGCOMPDIS
0
Disables the automatic
compensation triggered by
AVGTHRESH.
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6 COMPMETHOD 0 Defines the compensation method:
0: Compensate each CSx pin
independently (Typ.)
1: Compensate all CSx pins
together.
HYST
00
De
fines the proximity de
tection
hysteresis applied to
PROXTHRESH:
00: 32
01: 64
10: 128
11: 256
3:2 CLOSEDEB 00 Defines the Close debouncer applied
to PROXTHRESH:
00: Off
01: 2 samples
10: 4 samples
11: 8 samples
1:0 FARDEB 00 Defines the Far debouncer applied to
PROXTHRESH:
00: Off
01: 2 samples
10: 4 samples
11: 8 samples
0x0E RegProxCtrl8 R/W
7:4 STUCK 0000 Defines the proximity “stuck” timeout:
0000 : Off (Typ.)
00XX: STUCK x 64 samples
01XX: STUCK x 128 samples
1XXX: STUCK x 256 samples
3:0 COMPPRD 0000 Defines the periodic compensation
interval:
0000: Off (Typ.)
Else: COMPPRD x 128 samples
Sensor
Data R
eadback
0x20 RegSensorSel
R 7:2 Reserved 000000
RW 1:0 SENSORSEL 00 Defines which sensor’s data will be
available in registers RegUseMsb to
RegOffsetLsb (addr. 0x21 to 0x28):
00: CS0
01: CS1
10: CS2
11: CS3
0x21 RegUseMsb R 7:0 PROXUSEFUL 0x00 Useful current value.
Signed, 2's complement format.
0x22 RegUseLsb R 7:0 0x00
0x23 RegAvgMsb R 7:0 PROXAVG 0x00 Average current value.
Signed, 2's complement format.
0x24 RegAvgLsb R 7:0 0x00
0x25 RegDiffMsb R 7:0 PROXDIFF 0x00 Diff current value.
Signed, 2's complement format.
0x26 RegDiffLsb R 7:0 0x00
0x27 RegOffsetMsb
R/W
7:0 PROXOFFSET 0x00 Compensation offset current value.
Unsigned.
To force a value, MSB and LSB
registers must be written in
sequence and change is effective
after LSB.
0x28 RegOffsetLsb R/W
7:0 0x00
Software
Reset
0x7F RegReset W 7:0 SOFTRESET 0x00 Writing 0xDE resets the chip.
Table 10: Registers Detailed Description
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SX9500
Ultra Low Power, Four Channels
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9 A
PPLICATION
I
NFORMATION
9.1 Typical Application Circuit
Figure 30: Typical Application Circuit
9.2 External Components Recommended Values
Symbol Description Note Min Typ. Max Unit
CVDD Core supply decoupling capacitor - 100 - nF
CS
VDD
Host interface
supply decoupling capacitor
-
100
-
n
F
RPULL
Host interface pull
-
ups
+/
-
50%
-
10
-
k
Table 11: External Components Recommended Values
a SEMTECH E DIMENSIONS DIM INCHES MILLIMETERS MIN NOM MAX MIN NOM MAX A .020 .024 0.50 0.00 A1 .000 “ .002 0.00 “ 0.05 A2 (-006) 0.152 PIN1 E h .006 ,000 ,010 0.15 0.20 0.25 INDICATOR D .114 .110 .122 290 3.00 3.10 (LASERMARK) D1 .001 .067 .071 1.55 1.70 1.00 E .114 .115 ,1?2 2.90 3.00 3.10 E1 .061 .007 .071 1.55 1.70 1.00 9 .016550 0me L .0121.016I.020 0.30|0.40I0.50 I A2 N 20 20 __ m .00: 0.00 A syn-me hot: .004 0.10 IQIEIEI I I Y PLANE A1— «91—. I"I r" I 00000; M I 7 3 CI—f a2 1 D . :1 1 +5—_-‘—--—a 2D I III ‘ ‘ Cl unfinu N T o—DIZ-I ‘—ng . e bbb® c : 3 NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILL IMETERS (ANGLES IN DEGREES). 7. COPLANARITV APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS. 3. DAP Is 1.90 x 1.90m“.
WIRELESS & SENSING
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34
SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
10 P
ACKAGING
I
NFORMATION
10.1 Outline Drawing
Figure 31: Outline Drawing
a SEMTECH — ‘—K—. R —- DIMENSIONS ' UH U I DIM INCHES MILLIMETERS 141' (2 C (.114) (2.90) (C) I I: E G .063 2.10 "' E) + E H .067 1.70 1 E) :1 K .067 1.70 fl (—1 P .016 0.40 'I n D + y R .000 0.10 J x .003 0.20 X_.I |._ v .031 0.150 p .— z .146 3.70 NOTES: fl. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT VOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY‘S MANUFACTURING GUIDELINES ARE MET. 3. THERMAL VIAS IN THE LAND PATTERN OF THE EXPOSED PAD SHALL BE CONNECTED TO A SVSTEM GROUND PLANE. FAILURE TO DO 50 MAY CDMPROMISE THE THERMAL AND/OR FUNCTIONAL PERFORMANCE OF THE DEVICE.
WIRELESS & SENSING
Revision 4 February 4, 2014 © 2014 Semtech Corporation www.semtech.com
35
SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
10.2 Land Pattern
Figure 32: Land Pattern
a SEMTECH —
WIRELESS & SENSING
Revision 4 February 4, 2014 © 2014 Semtech Corporation www.semtech.com
36
SX9500
Ultra Low Power, Four Channels
Capacitive Proximity/Button Solution
Contact Information
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