Viper31 is a mains voltage converter for ac-dc power supplies from STMicroelectronics which allows PSUs to be constructed that consume only 20mW no-load at 230Vac, while delivering up to 18W when configured as a universal (85 – 265Vac) fly-back converter. Also, consumption is <430mW at 230Vac with a 250mW load. It can be used in isolated ...

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