Shutdown pin operation U1V11A

Hello, I am not having any success shutting down the U1V11A Step up Voltage regulator.
I have a 3.7volt Lipo connected to Vin. The shutdown pin is connected to an esp32 pin which is written High when I want the unit to power a motor driver and written Low when I want it to shutdown, and I have checked the voltage on this pin 3.2v High and .001v when Low. Everything has a common ground. But the voltage remains constant at Vout regardless of the High or Low on the Shutdown pin. Am I not understanding something?


I’m sorry you are having trouble with the shutdown feature on your U1V11A regulator. Could you post pictures that show all your connections including solder joints?


Thanks Claire, I simplified my code and guess what? It works. But the reason it seems like it wasn’t shutting down is because the ESP32 was entering deep sleep. Is that right the regulator will enable during deep sleep? I can still show you the circuit if you need to see it.

As noted in the connections section of the U1V11A product page the SHDN pin is internally pulled-up to VIN, so by default the regulator is enabled. From a quick look, it seems like the ESP32 might be capable of still controlling its GPIO pins when in deep sleep, so it might be possible to have it keep the regulator off. I suggest looking at the voltage on the pin you are using to control SHDN while running your program to experiment with that.