🛠️ Custom PCB Projects
Accumulator Motherboard
I designed the hardware for this board completely. It's a low-voltage motherboard that serves as the car's safety loop controller, dynamically managing the BMS, IMD, and BSPD relays while powering the Accumulator Isolation Relays (AIRs).
It also ties together precharge control and the onboard HV flyback power supply that feed the rest of the accumulator system.
HV Flyback Board
🧩 Schematic
As part of the power system, I worked on implementing a robust flyback converter using the LT8316 from Analog Devices. Designing a flyback involves careful selection of the transformer turns ratio, snubber network for transient suppression, and proper compensation for control loop stability. I also had to manage inrush current control and soft-start behavior by configuring external passives and validating waveforms under different loading conditions.
Attention to layout was critical, especially for high di/dt switching paths and grounding. I followed best practices for minimizing EMI, ensuring that the transformer, MOSFET, and output diode switching loops were tight and well-shielded. I also verified performance through both simulation and bench testing using differential probes and current shunts.
📈 Simulation
Since the flyback operates at high voltage, I simulated the circuit in LTspice to validate behavior before any physical testing, including the precharge and indicator light timing and current ramp. This allowed me to safely evaluate switching transients, snubber effectiveness, and transformer performance without risking hardware damage or personal safety. Simulation was a critical step to ensure the design was stable, efficient, and safe to implement.
Power Distribution Module
This module is responsible for safely distributing high voltage power across the car. Key features I implemented:
- Precharge sequence logic and shutdown interlocks
- A Voltage Indicator light on the Accumulator Container
- Contactor state transitions and fault detection
- State of Charge (SoC) monitoring via an INA236 current/voltage sense amplifier
- A main eFuse providing overcurrent protection, plus reverse voltage and overvoltage protection
- Per-fuse fault mapping on the onboard MCU when a fuse blows, it's broadcast as a CAN bus message so it shows up live in telemetry
The associated precharge circuitry was designed using an isolated op-amp for safe HV voltage monitoring and feedback control. This allowed the system to track precharge progress across an isolation boundary and safely trigger the main contactor once the voltage reached acceptable levels. Key skills applied here included analog design, power supply topology understanding, component derating, and safety-focused design methodology.
Other PCB
BSPD – Brake System Plausibility Device
I designed the BSPD to detect implausible braking behavior based on brake pressure and current input. Key features:
- Comparator-based detection circuit
- Analog filtering for noise reduction
- Analog Signal delay, to prevent false tripping
The board was built to meet Formula SAE shutdown safety rules and is heavilty inspected at competions.
🧩 Schematic
The BSPD schematic uses a comparator-based & logic gate circuit to watch for invalid acceleration/braking conditions, or detecting invalid sensor inputs (potentially from internal/external shorts) and triggers a shutdown latch via MOSFET logic when appropriate.
📈 Simulation
Simulations were done on falstad to ensure, comparator logic was correct and that false trips were being prevented by the shutdown circuit.
🧊 Interactive 3D model coming soon — BSPD
Drop /bspd.glb into /public to enable the viewer here.
TSSI – Tractive System Status Indicator
The TSSI is a simple but critical safety component. The TSSI gives us the status that the vehicle is in with respect to FSAE rules.
🧩 Schematic
The schematic follows rules abiding logic using low-side and high-side drivers paired with a 555 timer (used for LED flashing) to give the status of the vehicle.
🚧 PSFB – Phase Shifted Full Bridge Converter
This project is currently under construction. Check back soon for schematics, simulation results, and design notes on the phase shifted full bridge converter.