SLVSCY9B August 2015 – July 2016 DRV8871
The DRV8871 output consists of four N-channel MOSFETs that are designed to drive high current. They are controlled by the two logic inputs IN1 and IN2, according to Table 1.
|0||0||High-Z||High-Z||Coast; H-bridge disabled to High-Z (sleep entered after 1 ms)|
|0||1||L||H||Reverse (Current OUT2 → OUT1)|
|1||0||H||L||Forward (Current OUT1 → OUT2)|
|1||1||L||L||Brake; low-side slow decay|
The inputs can be set to static voltages for 100% duty cycle drive, or they can be pulse-width modulated (PWM) for variable motor speed. When using PWM, it typically works best to switch between driving and braking. For example, to drive a motor forward with 50% of its max RPM, IN1 = 1 and IN2 = 0 during the driving period, and IN1 = 1 and IN2 = 1 during the other period. Alternatively, the coast mode (IN1 = 0, IN2 = 0) for fast current decay is also available. The input pins can be powered before VM is applied.