DRV8251/A 48 V Half-Bridge Motor Driver from Texas Instruments

     Texas Instruments' DRV8251 and DRV8251A are integrated motor drivers with an N-channel half-bridge, charge pump, current regulation, protection circuitry, and current sense feedback (DRV8251A). The charge pump improves efficiency by supporting N-channel MOSFET half-bridge and 100% duty cycle drive.

     The DRV8251A has an internal current mirror architecture on the IPROPI pin for current sensing and regulation. This eliminates the need for high-power shunt resistors, saving board area and reducing system cost. The IPROPI current sense output allows a microcontroller (MCU) to detect motor stalls or changes in load conditions. The external voltage reference pin (VREF) determines the current regulation threshold during start and stop events without interaction with the MCU.

     The DRV8251 implements current regulation by comparing the analog input VREF with the voltage flowing through the current sense shunt resistor on the ISEN pin. Current limiting capability can significantly reduce high current during motor starting and stall conditions.

     A low-power sleep mode achieves ultra-low quiescent current consumption by shutting down most of the internal circuitry. Internal protection features include power supply undervoltage lockout (UVLO), output overcurrent protection (OCP), and thermal shutdown (TSD). The DRV8251/A devices feature pin-to-pin scalable RDS(ON) and supply voltage options to support a wide variety of loads and power supplies with minimal design changes.