mode 1：SW pin short to GND or VDD，how to short ？connect direct or use resistance（what is the best value？）， internal swith will not workmode 2 ：SW pin NC or connect to VM，but the internal swith is working still。in high temperature ，High efficiency ，Long life condition，what is the best of two ？

Visitor II

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STSPIN32F0 external 3.3V power supply issue

mode 1：SW pin short to GND or VDD，how to short ？connect direct or use resistance（what is the best value？）， internal swith will not work
mode 2 ：SW pin NC or connect to VM，but the internal swith is working still。
in high temperature ，High efficiency ，Long life condition，what is the best of two ？

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ST Employee

In mode 1 we suggest to connect the SW directly to GND (preferred option) to keep the internal switch latched off.

From the listed points of view there is no difference. Anyway the connection between the SW pin and GND is preferred in order to reduce the EMI.

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ST Employee

In mode 1 we suggest to connect the SW directly to GND (preferred option) to keep the internal switch latched off.

From the listed points of view there is no difference. Anyway the connection between the SW pin and GND is preferred in order to reduce the EMI.

"If you feel a post has answered your question, please click ""Accept as Solution"""