RaspberryPi_UPS_HAT

RaspberryPi UPS HAT, LIPO, Fan Control, I2C

Project goals:

• provide backup battery (LiPo 3.7V) with I2C status interface
• small footprint to integrate into given RaspberrryPi case (LABISTS Starter Kit)
• integrated fan control (temperature based)
• onboard programmer interface (ISP)
• I2C based RPI ups service for Battery supervision, logging and shutdown (systemd, python3, smbus)

Used items:

• Attiny 841 CPU
• LTC4054 LiPo Charger
• MT3606 Step-Up (LiPo > 5V)
• MIC5219 LDO (5V > 3.3V)
• USB Type-C connector
• resistors, capacitory (SMD 0805)

Schematic:

PCB: