PCB design for utility module

Utility hardware design for Audio Module, Analog Inputs, I2C/SPI sensors, RS232 and some digitial inputs.

• PCB assembly files are below pcb/assembly/
• PDF Schematic is below pcb/pdf_exports/

Components

• STM32F103 Bluepill board.
• 9 to 30V DC DC power supply.
• PAM8302AAS audio amplifier connected to STM32F1 PWM output
• Screwterminal for loudspeaker
• RJ45 connector for sensing e.g. gear, flaps, airbrakes postion
• RJ45 connector for CAN Interface and CAN transceiver
• RJ12 connector with analog and digital inputs
• 1.27mm pitch header for external I2C devices
• 1.27mm pitch header for RS232 and SPI interface

Pictures

Improvements for next version

• External connectors for voltage / I2C / RS232 are tiny. Increase size to e.g. 2.54mm pitch or chose a different connector.
• Make external i2c sensor voltage switchable to be able to perform a hard sensor reset.
• Replace C32 47uF with a sufficient voltage rating. The used one is only specified for up to 10V!