Odrive 3.6 Schematic: !free!

ODrive v3.6 is a high-performance brushless (BLDC) motor controller designed for robotics, CNC, and high-torque DIY projects. While it is a mature platform now marked as

(Not Recommended for New Designs) by the original manufacturer in favor of newer models like the

, it remains a standard for heavy-duty hobbyist applications due to its dual-axis capability and robust firmware support Schematic & Hardware Overview

The ODrive v3.6 hardware design is evolutionarily close to the v3.5, which was the last version to have its full design files publicly released by ODrive Robotics. 3.5 ODrive Schematic Release odrive 3.6 schematic

7. Communication Interfaces

• USB-C (connector + ESD protection)
• UART (via 3.3V logic level pins)
• CAN bus (with transceiver like SN65HVD230)
• Step/Dir input (for simple stepper replacement mode)

Why the Schematic Matters

Before we look at the circuitry, let’s clarify why you need the schematic.

• Troubleshooting: If you blow a phase or short a GPIO, the schematic tells you which component to probe.
• Custom Firmware: If you are modifying the STM32 firmware, you need to know which pins control the PWM timers or ADC reads.
• Hardware Modding: Want to add external current sensors or replace the onboard LDO? The schematic is your map.
• Repair: ODrive boards are expensive. The schematic allows you to identify and replace blown capacitors, gate drivers, or even the main MCU.

Where to find it: The official ODrive 3.6 schematic is available on GitHub in the odrive/hardware repository. The file is typically named ODrive-v3.6-Rev<X>.pdf.

3. The Power Stage (Gate Drivers & MOSFETs)

This is the most complex part of the ODrive 3.6 schematic. Each motor has a 3-phase inverter bridge. For Motor 0, look for: ODrive v3

• Gate Driver IC (e.g., DRV8301 or FD6288): This chip takes 3.3V PWM signals from the STM32 and converts them into high-current, high-voltage signals to drive the MOSFETs. Crucially, the schematic shows the bootstrap circuitry for the high-side FETs.
• MOSFETs (e.g., IPT020N10N3): These are the big, low-inductance power transistors. The schematic arranges them in three half-bridges. Look for the Schottky diodes placed across the FETs—these catch flyback voltage during commutation.
• Phase Outputs: M0_A, M0_B, M0_C go directly to the motor terminals (J2).

Common Failure Point: On the schematic, find the BST (bootstrap) pins on the gate driver. If the bootstrap capacitor fails (usually a 100nF ceramic), the high-side MOSFET won’t turn on, and the motor will twitch or vibrate without spinning.

2. The Brain: STM32F405 (MCU Section)

The ODrive 3.6 uses the STM32F405RGT6. The schematic reveals the genius of the pin mapping.

• Timers: The F405 has advanced timers (TIM1, TIM2, TIM3, TIM4, TIM8). On the schematic, you will see TIM1_CH1 routed to the gate driver for Motor 0 Phase A. This is where PWM is generated.
• ADC (Analog-to-Digital Converter): The schematic shows dedicated ADC pins reading the current sense amplifiers. For example, ADC1_IN0 reads I_M0_A. Low latency here is why the ODrive can do 100,000+ loop cycles per second.
• Communication: PA9 and PA10 are USART1 (UART header). PA11 and PA12 are USB DM/DP. The schematic also pulls out PB12 and PB13 for SPI (for absolute encoders like AS5047P).

Pro Tip: If you are designing a custom breakout board, never assign these specific timer/ADC pins to anything else. The firmware expects them at hard-coded addresses. USB-C (connector + ESD protection) UART (via 3

Critical Design Considerations from the Schematic

• Ground Planes: Separate analog (sensor) and power (MOSFET source) grounds, joined at a single star point.
• High-Voltage Creepage: Generous spacing (>1.5mm) between VBUS and low-voltage traces.
• Decoupling: 0.1µF ceramic caps placed within 2mm of every IC power pin.

4. Layout Implications on the Schematic

The schematic implies certain layout realities that affect performance:

• Capacitance: The schematic shows a bank of electrolytic capacitors on the power input. On the v3.6 board, these are sometimes physically distant from the MOSFET legs. This increases inductance, leading to voltage spikes on the DC bus during switching transitions, which can stress the MOSFETs.
• Thermal Coupling: The schematic does not show the thermal relationship between the DRV8301 and the power FETs, but the PCB layout places them close. In high-current scenarios, the heat from the MOSFETs can migrate to the DRV8301, causing the driver to overheat and shut down the board unexpectedly.

How to Read the ODrive Schematic for Troubleshooting

Let’s say your Motor A is not spinning. Here’s how the schematic guides you:

1. Power check: Measure TP_VBUS_HV, TP_5V, TP_3V3. Are they correct?
2. Gate driver: Check if DRV8301 (U3) has EN (enable) high. Verify its 5V and 12V (internal charge pump) outputs.
3. PWM signals: Use an oscilloscope on the gate resistor inputs (e.g., R1, R2, R3). Are symmetric 3.3V PWM waveforms present from the STM32?
4. Current sensing: Unpower the motor, spin by hand, and check the op-amp outputs (e.g., U5 U6 U7) for small voltage variations.
5. Encoder feedback: Is the encoder’s A/B signal reaching the STM32 timer pins? Check continuity from encoder header to MCU pin using the schematic.