STMicroelectronics' H-Bridge Gate Drivers are Designed for DC Motor Drives in Automotive Applications

     STMicroelectronics' L99H02 is designed to drive 4 external N-channel MOS transistors in an H-bridge configuration for DC motor drives in automotive applications. It integrates a freely configurable current sense amplifier. An integrated standard serial peripheral interface (SPI) controls the device and provides diagnostic information. Implemented interface pins for external MOSFET thermal sensors. Dual power supply, VS and VCC act on L99H02. The power supply Vs provides the charge pump, and the VCC of the gate driver is used for the logic section, the SPI of the device, and the output stage of the current sense amplifier. L99H02 is activated by the enable input. With the enable input floating (unconnected) or low, the device is in standby mode, reducing current consumption to 5 μA.

     DIR and PWM inputs control external H-bridge transistor drivers, set direction and PWM (duty cycle and frequency). The L99H02 implements many diagnostic functions (overload, power supply over and under voltage, charge pump low, watchdog, temperature warning and internal/external thermal shutdown) to protect itself and external devices. The Current Sense Amplifier (CSA) supports current measurement of DC motors at both shunts. Gains of 50, 20 or 10 are SPI programmable. A dual stage charge pump ensures proper HS gate drive. A watchdog function is used for continuous MCU monitoring.