STEVAL-ISA015V2: 100W, 24V @ 4.3A, 230 or 400 VAC


The flyback converter is a popular choice in applications where the required power is normally less than 200W. The main reasons explaining its popularity are its simplicity, low cost and high efficiency for a small number of active components.

In switching converters power loss is caused by power dissipation within the parasitic elements of both passive and active components. Power loss in passive components can be reduced by selecting suitable passive components and carefully designing the transformer.

The aim of the proposed zero-voltage switching control is to reduce switching loss (in this application, the primary switch turn-on loss). The zero-voltage switching control also greatly reduces the EMI generated by primary switch turn-on.

Conduction loss is generated with the device fully turned-on, by the voltage drop across the conducting device. The proposed use of the Emitter-Switched Bipolar Transistor (ESBT) as the primary switch reduces conduction loss efficiently. Moreover, with its low saturation voltage and fast switching capability compared to an IGBT or a bipolar junction transistor (BJT), the ESBT is well suited for this use.


Manufacturer STMicroelectronics
Category AC/DC and DC/DC Conversion
Sub-Category AC/DC SMPS - Single Output
Eval Board Part Number 497-5679-ND
Eval Board Supplier STMicroelectronics
Eval Board -
AC Voltage 230 V
Outputs and Type 1 Isolated
Voltage Out 24 V
Current Out 4.3 A
Output Power 100 W
Features Over Current Protection
Under Voltage Protection, Brown-Out
Efficiency @ Conditions >82%, 620VDC, 24V @ 20 ~ 100 W Out
>81%, 450VDC, 24V @ 20 ~ 100 W Out
No-load Input Power @ Voltage
Switching Frequency 50 kHz
Internal Switch No
Component Count + Extras 56 + 2
Voltage In 160 ~ 240 or 320 ~ 480 VAC
Design Author STMicroelectronics
Application / Target Market AC Adapters
Battery Chargers
LCD TV / Monitor
Welding Machines
Main I.C. Base Part L6565

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