STEVAL-ISA014V1 Datasheet, PDF (2/5 Pages) STMicroelectronics – VIPer12A travel adaptor 3.6W output

General circuit description
1 General circuit description
STEVAL-ISA014V1
The circuit is a standard fly-back converter with secondary current and voltage regulation
driving the VIPer12A feedback pin through an optocoupler.
The power losses are distributed at 6V / 600mA output power as follows:
● 400mW in the output diode
● 700mW in the VIPer12A
● 300mW in the transformer
● 380mW in the shunt resistor
Overall efficiency is 67%.
If the losses in the shunt resistor are considered as available power, the converter efficiency
becomes 74%. This is possible by using a secondary controller like ST's TSM101.
In standby, the demo board consumes less than 100mW at 100Vdc and 120mW at 380Vdc.
The major contribution to the standby consumption is the VIPer12A own consumption and is
independent from input voltage.
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