Hello,
I'm experiencing an issue with the internal LDO regulator on the STSPIN32G4 MCU. The LDO is outputting 4.1V instead of the expected 3.3V, and I've been unable to resolve it despite trying multiple configurations.
Problem Details:
- Target: 3.3V VDD from internal LDO
- Actual output: 4.1V when input voltage > 4V
- Behavior: When input voltage is 3.33V, output is 3.05V (which seems reasonable given dropout), but when input is >4V, output remains at ~4.1V instead of regulating to 3.3V
What I've Tried:
- All configuration options listed in Section 5.1.2 of the datasheet
- Replicated the three circuit configurations from Figure 9 ("3.3V LDO regulator supplied through VCC")
- Various register settings without success
Expected Behavior: The LDO should regulate the output to 3.3V whenever the input voltage is above 3.3V + dropout voltage, correct?
I've attached my schematic and screenshots showing the output voltages. Any insights into what might be causing this behavior or what configuration I might be missing would be greatly appreciated.
Thank you!
