L99H02 H-Bridge Gate Driver

STMicroelectronics' L99H02 is designed to drive 4 external N-channel MOS transistors in H-bridge configuration for DC-motor driving in automotive applications. A free configurable current sense amplifier is integrated. The integrated standard serial peripheral interface (SPI) controls the device and provides diagnostic information. An interface pin for the thermal sensors of the external MOSFETs is implemented. A dual power supply, V_S and V_CC acts on L99H02. The power supply Vs supplies the charge pump and the gate drivers instead V_CC is used for the logic part, the SPI of the device and for the output stage of the current sense amplifier. L99H02 is activated by the Enable input. In case of enable input floating (not connected) or low the device is in standby mode minimizing the current consumption down to 5 μA.

The DIR and PWM inputs control the drivers of the external H-bridge transistors setting direction and PWM (duty cycle and frequency). L99H02 implements many diagnostic functions (overload, power supply over- and undervoltage, charge pump low, watchdog, temperature warning, and internal/external thermal shutdown) to protect itself and external devices. The current sense amplifier (CSA) supports the current measurement of the DC motor at two shunts. A gain of 50, 20, or 10 is SPI programmable. A dual-stage charge pump guarantees the correct HS gate driving. Watchdog function is implemented for a constant MCU monitoring.