Motor drive circuit design
The development board integrates two AT8236 single-channel brushed DC motor driver chips for driving two motors.
Motor drive circuit
The AT8236 chip is a single-channel H-bridge motor driver that supports a wide voltage input of 5.5-36V; internal protection functions include over-current protection, short-circuit protection, under-voltage lockout and over-temperature protection.
H-bridge control
Input pins IN1 and IN2 control the output state of the H-bridge. The following table shows the logical relationship between the input and output:
| IN1 | IN2 | OUT1 | OUT2 | Function |
|---|---|---|---|---|
| 0 | 0 | Z | Z | Coast, Sleep |
| 1 | 0 | H | L | Forward |
| 0 | 1 | L | H | Reverse |
| 1 | 1 | L | L | Brake |
When using PWM control to achieve speed regulation, the H-bridge can operate in two different states: fast decay or slow decay.
| IN1 | IN2 | Function |
|---|---|---|
| PWM | 0 | Forward PWM, fast decay |
| 1 | PWM | Forward PWM, slow decay |
| 0 | PWM | Reverse PWM, fast decay |
| PWM | 1 | Reverse PWM, slow decay |