Pytrack PWR_EN, and 3V3 External IO pins

[gregcope]

Hi

On the pytrack there are a few pins marked on the External IO Header;

Pin 2 PWR_EN
Pin 3 3V3_Pymodule
Pin 4 3V3_Sensors

What are those for? Are any powered on when awake, and powered off when in Deepsleep? I am looking for a pin to power a DS18B20 ONLY when awake.

[seb]

@gregcope

Pin 3 3V3_Pymodule - This power supply is always switched on
Pin 4 3V3_Sensors - This power supply is only switched on when the Pytrack is awake, when it goes to sleep mode it turns off
Pin 2 PWR_EN - You can use this to externally toggle the sleep mode

[jcaron]

@seb looks like it’s been a long week :-) You have severely mixed up the pins and their functions...

[seb]

@jcaron oh gosh, sorry I've been running around like a headless chicken today.

I have updated the pin numbers in the previous post, but I have verified the functionality is definitely correct.

[gregcope]

@seb brilliant. Just what i needed.

Might be worth putting that in the docs as the ability to have a pin that is only on when powered is brilliant for low power sensor nodes that want to toggle the sensors on/off with the board to save power.

[svonbentzel]

@seb said in Pytrack PWR_EN, and 3V3 External IO pins:

@gregcope

Pin 3 3V3_Pymodule - This power supply is always switched on
Pin 4 3V3_Sensors - This power supply is only switched on when the Pytrack is awake, when it goes to sleep mode it turns off
Pin 2 PWR_EN - You can use this to externally toggle the sleep mode

Old thread, but I need help:

The pwr_en pin is to power down the pycom board right?

Connect this pin to gnd with a button or with a switch?