Requirements

Powered by a 3S (12V) battery input.
- In the context of integrating with the ELRS board, an XT60 connector should be provided, and additional PWM input from a header pin should be placed (unsure of this requirement given we want to use DSHOT).
- 3x solder pads for BLDC connection.
- Supports DSHOT input.
  - More resistant to noise in transmission versus PWM, as DSHOT is a digital protocol.
- An “OPTO” ESC, meaning no BEC is included.
Must use the AM32 open-source firmware for motor control. (https://am32.ca)
- This uses a sinusoidal algorithm to control the BLDC. (no FOC)
- Has a strict MCU compatibility list (we would preferably use a smaller ST chip)
- Sensorless operation using back EMF. No Hall sensing or current sense
Designed around an target motor (in Houston): https://innov8tivedesigns.com/cobra-cm-2217-20-brushless-motor-kv-950.html
- Standard 3-phase brushless DC motor with 12 stator windings and 14 exterior magnet poles, meaning 4 coil windings per phase. Designed for 3S/4S power source.
  - With a higher density of magnet poles in the rotor, smoother torque is able to be produced by the motor. The rotor being on the outside gives more torque as well.
- Maximum continuous current of 20 Amps.
  - Maybe 25A or 30A maximum burst current.
  - Should be accounted for during FET selection.

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