This is my second attempt to use a Pimeroni OnOff Shim at my Raspberry Pi 4B to build a so called Phoniebox. I receive repeatable “Under-voltage detected!” messages if using the OnOff Shim inside my setup: On my Rapsberry Pi 4B I connected analog speakers (Trust Compact 2.0, 6 Watts peak). The Pow…

It could be the jumper wires from the shim to the Pi. The thinner the wire the more resistance they have and the bigger the voltage drop across them. The official Pi 4 power supply has 18 gauge wires in it. The jumper wires are I think 24 gauge? Which is a lot thinner If you can double up your ju…

I already use jumper wires from Elegoo (28 awg) and connected Pis pins 2,4 (5 Volts) and 6,9 (Ground) to the OnOff Shim. I’d like to put the Pi inside a case with a cooling fan (eg. Miuzei case). Therefore connecting the Shim directly or through an extension board (AZDelivery GPIO extension board) …

28 gauge is thin by the way, the higher the number the smaller the diameter of the wire. Also, does the on off shim have a header on it? Just wondering what the jumpers are plugged into? The On Off shim has a 2.5A limit, I’m not sure thats an issue just pointing it out. Thats all you’ll get anyway…

My power bank (EasyAcc PB26000MS) is able to supply DC 5 Volts, max. 4.8 Ampere output. I’m wondering where the “2.5A” limit comes from, because the USB protocol specification on Wikipedia mentions up to 5A/5V on Battery Charging (BC) 1.2 otherwise it provides max. 1.5A at 5V?! FYI: On my 1st Shim…

Just a question from a rookie: If I use a AZDelivery GPIO Extension Board place 2 times an OnOff Shim on top of the GPIO connectors connect on each Shim an USB cable from my power bank (4.8 Ampere only). … would I be able to provide in 4.8A (2x 2.5A) in total to my Raspberry Pi 4?

The ON Off shim itself may have a 2.5A limit based on the components used? You’d have to ask Pimoroni if thats what the limit is based on. It may also be because the recommended power supply to be used with it, the Official Pi Foundation Power supply is limited to 2.5 A. All I can tell you is the pr…

OnOff Shim @ Pi 4 - Unter-voltage issues?

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GordonTGopher February 23, 2020, 4:34pm 8

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OnOff Shim @ Pi 4 - Unter-voltage issues?

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