Cheap Bipolar Power Supply

The Circuit

Attention:

You definately should connect the 0V line to protective earth.

Also, lots of fake HiLink modules out there. Beware! Genuine ones DO have a serial number sticker attached to one of their sides.

HiLink Modules to be found here:

HLK-PM01: https://www.aliexpress.com/item/5-pcs-HLK-PM01-AC-DC-220V-to-5V-Step-Down-Power-Supply-Module-Intelligent-Household/32319202093.html

HLK-PM03: https://www.aliexpress.com/item/HLK-PM03-AC-DC-220V-to-3-3V-Step-Down-Buck-Power-Supply-Module-Intelligent-Household/32586663935.html

HLK-PM12: https://www.aliexpress.com/item/AC-DC-220V-to-12V-Buck-Step-Down-Power-Supply-Module-Converter-Intelligent-Household-Switch-HLK/32585820323.html