SLVSD19A June 2015 – July 2015 DRV8881
PRODUCTION DATA.
The DRV8881 is an integrated motor driver solution for bipolar stepper motors or single/dual brushed-DC motors. The device integrates two NMOS H-bridges and current regulation circuitry. The DRV8881 can be powered with a supply voltage between 6.5 and 45 V, and is capable of providing an output current up to 2.5 A peak or 1.4 A rms per H-bridge. Actual operable rms current will depend on ambient temperature, supply voltage, and PCB ground plane size.
A simple PH/EN (DRV8881E) or PWM (DRV8881P) interface allows easy interfacing to the controller circuit.
The current regulation is highly configurable, with several decay modes of operation. The decay mode can be selected as a fixed slow, mixed, or fast decay.
In addition, an smart tune mode can be used which automatically adjusts the decay setting to minimize current ripple while still reacting quickly to step changes. This feature greatly simplifies stepper driver integration into a motor drive system. Smart tune is only available on the DRV8881E.
The PWM off-time, tOFF, can be adjusted to 10, 20, or 30 μs.
An adaptive blanking time feature automatically scales the minimum drive time with output current. This helps alleviate current waveform distortion by limiting the drive time at low-currents.
A torque DAC feature allows the controller to scale the output current without needing to scale the analog reference voltage inputs AVREF and BVREF. The torque DAC is accessed using digital input pins. This allows the controller to save power by decreasing the current consumption when not required.
In the DRV8881P, a parallel mode allows the user to parallel the two H-bridge outputs in order to double the current capacity.
A low-power sleep mode is included which allows the system to save power when not driving the motor.