About a year ago I started to use the FRDM-KL25Z board (RevD). Finally, I had it in my hands: the RevE board from Mouser 🙂 Using the RevD board, I faced several problems:

1. 3.3V supply voltage drop because of low-cost diode D1 (see this post)
2. Hard to use USB host mode, as no 5V supplied to the USB bus (see this post)
3. No 5V generated from V_IN (see this post)

The good news: all of them have been improved 🙂 in the FRDM-KL25Z RevE Schematics:

FRDM-KL25Z RevE Board

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