Charger testing rig

Electrically, there is not much at play. We use the USB connector to power a simple transistor current source and light an LED. See image for the PCB design. The version pictured is V2 since the original used incorrect pin assignments for the USB header. Frustratingly, we did not discover this until after a batch of PCBs had been fabricated and delivered.

In practice, we omitted R3, as we found 100 Ω provides sufficient brightness.

• Rev 3

  • updated footprint of green LED to horizontal for clarity
• Rev 2

  • fixed reversed power connections