The idea behind this project is to create a ultra-compact USB-C bi-directional charger for e-bikes, easy to integrate within top tube or anywhere else. Main features of the system are the following:

• Extremely efficient DC-DC with CC/CV algorithm to charge up to 48V e-bike battery from as low as 9V USB voltage.
• Reversed USB-C charge for accesories from e-bike battery.
• Fully configurable USB-Power Delivery protocol by programming STM32G431 microcontroller.
• Power channel hardware-managed using Power Switches based on 2 P-MOSFET to secure against shorts.
• Maximum charging current managed by analog potentiometer over I2C to tightly control charging conditions.
• PCB designed to meet thermal requirements and allow to integrate heatsinks to efficiently dissipate heat.
• NTC sensor to accurately measure thermal conditions and keep the system under control.
• CANbus communication to integrate the system into e-bike communication channel.
• CANbus secured access from one of differential pair on USB-C connector, controlled by STM32 and analog MUX.
• Expansion port to add a secondary PCB and expand functionality over Hirose DF12NB(3.0)-14DS-0.5V(51) connector.
• UART interface to debug system.
• STM32 programming port based on Tag-Connect standard interface.
• 64Mb SPI flash memory to permanently store data.