nRFMicro 1.2

1.2 revision (with the High Voltage mode aka internal 25mA LDO) is the first slim version. The upcoming 1.3 is supposed to ditch high voltage mode in favor of the regulated output voltage.

Minor issues

• Won't flash via SWD with the internal 1.8V from LDO, needs external 3.3V soldered to module VDD.
• Onboard blue LED is super-dim at 1.8V (can be set to 3.3V programmatically), use red or green LED.
• Power MOSFET can't close at 1.8V, needs configuring internal LDO (UICR register) to 3.3V

New features

• Single sided, 3.5mm unshielded (standard Pro Micro is 3.75 mm, nRFMicro 1.1 is 6.35 mm)
• Software-controlled (EN/STAT) charger (MCP73811/MCP73831), non-chargeable batteries support
• Power MOSFET now controls external VCC line instead of the GND line (no more reset button issues)
• High voltage mode (1.8V core VCC, internal LDO), unregulated 3-5V output from the battery/USB source

Partlist update for 1.2

• Midmount USB-C connector for 1.6 mm PCBs
• 10 uH inductor (0603 package)
• MCP73811 (should also work with an old MCP73821, with 10K software PROG pulldown for 100 mA)
• Schottky 1N5819 diode is now SOD-323 (smaller)
• 820K and 2M resistors (0603 packages) for the battery voltage measuring circuit

Firmware changes

• Charger have to be enabled either with EN pin (MCP73811) or pull-down on PROG (MCP73831)