SLVSDS7B August 2019 – November 2019 DRV8876
The DRV887x family of devices are brushed DC motor drivers that operate from 4.5 to 37-V supporting a wide range of output load currents for various types of motors and loads. The devices integrate an H-bridge output power stage that can be operated in different control modes set by the PMODE pin setting. This allows for driving a single bidirectional brushed DC motor, two unidirectional brushed DC motors, or other output load configurations. The devices integrate a charge pump regulator to support more efficient high-side N-channel MOSFETs and 100% duty cycle operation. The devices operate from a single power supply input (VM) which can be directly connected to a battery or DC voltage supply. The nSLEEP pin provides an ultra-low power mode to minimize current draw during system inactivity.
The DRV887x family of devices also integrate current sense output using current mirrors on the low-side power MOSFETs. The IPROPI pin sources a small current that is proportional to the current in the MOSFETs. This current can be converted to a proportional voltage using an external resistor (RIPROPI). The integrated current sensing allows the DRV887x devices to limit the output current with a fixed off-time PWM chopping scheme and provide load information to the external controller to detect changes in load or stall conditions. The integrated current sensing out performs traditional external shunt resistor sensing by providing current information even during the off-time slow decay recirculating period and removing the need for an external power shunt resistor. The off-time PWM current regulation level can be configured during motor operation through the VREF pin to limit the load current accordingly to the system demands.
A variety of integrated protection features protect the device in the case of a system fault. These include undervoltage lockout (UVLO), charge pump undervoltage (CPUV), overcurrent protection (OCP), and overtemperature shutdown (TSD). Fault conditions are indicated on the nFAULT pin.