Industrial Burner PCB Design & Optimization

PCB Design for Industrial Burner Control Unit based on STM32G474RE We are looking for an experienced PCB designer to convert our working and client approved Burner Control Unit prototype into a production ready PCB. The firmware and control logic are complete and validated. We need a reliable, safety focused hardware design with isolated flame ionization sensing, thermocouple input, Modbus RTU communication and relay based valve and ignition control, suitable for an industrial enclosure. Hanyaa Auto Technologies has developed a Burner Control Unit for an industrial plant. The unit manages the complete burner sequence including prepurge, spark ignition, pilot flame proving through ionization sensing, main flame supervision, flame loss detection and post purge. The system has been demonstrated to the client and approved to move into PCB integration and enclosure development. The design must follow the intent of EN 298 for automatic burner control systems. Schematic capture from our existing prototype circuits and block level requirements Component selection review with focus on industrial grade and readily available parts in India PCB layout with proper separation of high voltage, mains, isolated analog and low voltage digital sections Creepage and clearance planning suitable for burner control safety requirements Low noise layout for the flame ionization sensing front end, which currently reads lower than expected on the prototype Design for manufacturing and assembly review Mechanical coordination so the board fits the enclosure we are developing Support during first prototype bring up and one design revision Main Circuit Blocks STM32G474RE microcontroller core with SWD programming header, crystal and reset circuit Flame ionization sensing using AMC3301 isolated amplifier with a transimpedance amplifier stage and INA228 power monitor on a dedicated I2C bus Single flame rod used for both spark and sensing, requiring careful protection of the sensing front end from the ignition pulse Ignition transformer control around 5 kV for approximately 3 seconds, switched through a relay Relay outputs for pilot gas valve, main gas valve, blower and alarm Thermocouple input using MAX31856, supporting multiple types including S and B selectable in firmware Character LCD on I2C with a front panel connector Modbus RTU over isolated RS485 Isolated power supply section for analog and communication domains Digital inputs for pressure switches, limit switches and reset button with suitable filtering and protection Status LEDs and test points for validation