Drive.DC.H
H-bridge DC motor driver for the Drive.DC.H tile (rev a).
Embeds the TI DRV8214, a full H-bridge motor driver with integrated current sensing, stall detection, and voltage/speed regulation.
Key specifications: - Output: full H-bridge, 4 A peak / 2 A RMS continuous - Supply: 1.65-11 V motor supply (VM), 1.65-5.5 V logic (VCC) - R_DS(on): 240 mOhm (high + low side total) - Regulation: voltage or speed, via internal PI loop - Current sense: internal current mirror (IPROPI), 3 gain settings - Stall detect: hardware, configurable via IPROPI/VREF threshold - Ripple count: sensorless position/speed via commutation ripples - Protection: UVLO, OCP, OVP, thermal shutdown
The tile also exposes EN/PH control pads (pads 2, 3) for direct GPIO-based motor control without I2C, and an analog current proportional output on pad 6 (NPROP/IPROPI) that mirrors the motor winding current scaled by the CS_GAIN_SEL setting. External pad control still requires a one-time I2C write to enable the output stage (EN_OUT=1). A future driver revision will add pad-control mode helpers.
The DRV8214 integrates a sensorless ripple counting algorithm that counts commutation ripples in the motor current waveform to estimate rotor position and speed without external encoders or Hall sensors. In speed regulation mode (DRIVE_DC_H_MODE_SPEED), the chip's internal PI loop maintains constant motor speed across varying supply voltages and loads. The ripple count and estimated speed can be read at any time via get_ripple_count() / get_speed(). Accurate ripple counting requires motor-specific tuning of the INV_R, KMC, and filter parameters (see DRV8214 datasheet section 9.2.3.1).