DRV8251/A 48 V H-Bridge Motor Drivers
Texas Instruments' N-channel brushed DC drivers offer current regulation, a charge pump, and protection circuitry
Texas Instruments' DRV8251 and DRV8251A are integrated motor drivers with an N-channel H-bridge, a charge pump, current regulation, protection circuitry, and current sense feedback (DRV8251A). The charge pump improves efficiency by supporting N-channel MOSFET half-bridges and 100% duty-cycle driving.
The DRV8251A has internal current mirror architecture on the IPROPI pin to implement current sensing and regulation. This eliminates the need for a large power shunt resistor, saving board area and reducing system cost. The IPROPI current-sense output allows a microcontroller (MCU) to detect motor stalls or changes in the load conditions. The external voltage reference pin (VREF) determines the threshold of current regulation during start-up and stall events without interaction from an MCU.
The DRV8251 implements a current regulation feature by comparing the analog input VREF and the voltage across a current-sense shunt resistor on the ISEN pin. The ability to limit current can significantly reduce large currents during motor startup and stall conditions.
The low-power sleep mode achieves ultra-low quiescent current draw by shutting down most of the internal circuitry. Internal protection features include supply undervoltage lockout (UVLO), output overcurrent (OCP), and thermal shutdown (TSD). The DRV8251/A devices come in pin-to-pin, scalable RDS(ON), and supply voltage options to support various loads and supply rails with minimal design changes.
- N-channel H-bridge brushed DC motor driver
- Operating supply voltage range: 4.5 V to 48 V
- Pin-to-pin, RDS(ON), voltage, and current sense/regulation variants (external shunt resistor and integrated current mirror)
- DRV8251: 4.5 V to 48 V, 450 mΩ, shunt
- DRV8251A: 4.5 V to 48 V, 450 mΩ, mirror
- High output current capability: 4.1 A peak
- PWM control interface
- Logic inputs: 1.8 V, 3.3 V, and 5 V
- Integrated IPROPI current sensing (DRV8251A) for stall detection and current regulation
- Low-power sleep mode: <1 µA at VVM = 24 V, TJ = +25°C
- Small package and footprint: 8-pin HSOP with a PowerPAD™, 4.9 mm x 6.0 mm
- Integrated protection: VM UVLO, auto-retry OCP, and TSD
- Vacuum robots
- Washers and dryers
- Coffee machines
- POS printers
- Electricity meters
- ATMs (automated teller machines)
- Surgical equipment
- Electronic hospital beds and bed controls
- Fitness machines