Powering the RPi, Part 2
Table of contents
Read Part 1!
I updated and corrected many sections and pictures at my first part, which you can read here.
A look back at this blog is highly recommended.
Where to put the wires?
For the sake of completionismn here are the missing RPi and the points to hook up some external voltages.
Raspberry Pi Zero
The RPi Zero is simply a downsized original version, so you need to find the inductor to remove and the capacitor to hook on your external voltage.
Both components are located above the SoC, but sometimes they are not labeled.
On some RPi Zero the inductor is labeled as L3, but the location is always the same.
Compute Modules 1
Like the RPi Zero, the CM1 is also a reshaped version of the original Raspberry Pi.
Use C19 to hook up your external voltage, located above the SoC and remove L1 on the backside of the module. That’s it.
Here you can see the schematics:
Compute Module 3/3+
For the CM3, your only option to get more voltage is to inject it. I couldn’t spot a voltage divider to modify the generated VDD_CORE.
On the RPi2/3 you had two options.
Right above the SO-DIMM-connector you can hook up your external voltage to C42 and remove L1.
Since the CM3 and CM3+ are PCB-identical this voltmod works on both modules, but the software limitation of 1,600 MHz is still there.
Unfortunatelly you don’t find any useful schematics for identification purposes. The reduced schematics don’t show information about the circuits for generating the VDD_CORE.1