A6986H Automotive Synchronous Step-Down Switching

By STMicroelectronics 117

A6986H Automotive Synchronous Step-Down Switching

STMicroelectronics' A6986H automotive-grade device is a stepdown monolithic switching regulator able to deliver up to 2 A of output current. The output voltage adjustability ranges from 0.85 V to VIN. There are two fixed voltage versions, 5 V and 3.3 V, which allow for saving external components and improving accuracy. The 100% duty cycle capability and the wide input voltage range meet the cold crank and load dump needs of automotive systems. The low consumption mode (LCM) is designed for applications active during car parking, so it maximizes the efficiency at light load with controlled output voltage ripple. The low noise mode (LNM) makes the switching frequency constant and minimizes the output voltage ripple overload current range, meeting the low noise application requirements such as car audio. The output voltage supervisor manages the reset phase for any digital load (μC, FPGA). The RST open collector output can also implement output voltage sequencing during the power-up phase. The synchronous rectification, designed for high efficiency at medium-heavy load, and the high switching frequency capability make the size of the application compact. Pulse by pulse current sensing on both power elements implements an effective constant current protection.

  • Low consumption mode with only 30 μA quiescent current
  • Low noise mode with forced PWM
  • Adjustable switching frequency from 250 kHz to 2 MHz
  • Adjustable or fixed output voltage (3.3 V and 5 V)
  • Embedded output voltage supervisor
  • Synchronization
  • Adjustable soft-start time
  • Overvoltage protection
  • Designed for automotive systems
  • Battery-powered applications
  • Car body applications (LCM)
  • Car audio and low noise applications (LNM)