I have been looking for a solution for my use-case and the push-button power switches (https://www.pololu.com/product/2808) seem to fit nicely (not totally, but it seems to be the best solution):
I have a touchscreen Display (https://www.elecrow.com/wiki/index.php?title=5_inch_HDMI_800_x_480_Capacitive_Touch_LCD_Display_for_Raspberry_Pi/_PC/_SONY_PS4) connected to a Raspberry PI 3B+ via HDMI and USB.
To be able to save power (the setup is running from a power bank), I want to be able to turn the display off via a button and programmatically. This can not be done straightforward (and I can not use the power button on the display), so I want to use the power switch.
The plan is to break out the USB and have the power switch control the 5 V USB power line. I know that this is not according to the USB protocol, but I am willing to take that risk.
Now my questions:
- USB works at 5V, however the min voltage for the SV version (and up) is 4,5V - should I stick to the LV version?
- There are 2 Vin and 2 GND connections. Does that mean I can run two lines through the power switch and control them both at once (or only use either one if the Vin inputs)?
- is there another solution? I saw that you have a USB multiplexer also (https://www.pololu.com/product/2596). Can / Should I maybe use that and leave IN2 unconnected and switch to that in order to turn off USB power?
Thanks in advance!