
In face I can switch the valve ON and OFF using power from 3 V pin of ESP32 by manually switching the polarity. But to control it by software I need some H bridge.
My supply is either 3 V pin of ESP32 or directly by 3.7 V lipo battery.
I built H Bridge using four 2N2222 BJT transistors. The bridge works fine with LEDs but cannot operate valve due to voltage drop. For the same reason of voltage drop, I dropped the idea of using L298N or L293D motor drives.
Can someone please recommend some good H bridge chip for this purpose which can operate with 3 V and a few milli amp current without losing voltage?