FTM Board Club
38 V, 1.5 A synchronous step-down switching regulator

The STEVAL-L6981NDR is based on the L6981NDR synchronous monolithic step-down regulator delivering up to 1.5 A dc.

Click to request a related board:

    • STEVAL-L6981CDR for 1.5A in low consumption mode (LCM)

    • STEVAL-L6982CDR for 2A in low consumption mode (LCM)

    • STEVAL-L6982NDR for 2A in low noise mode (LNM)

Its wide input voltage range makes the solution suitable for a broad range of applications. 

The device implements peak current mode architecture in a SO 8L package with internal compensation to minimize design complexity and size. 

The L6981 is available in low consumption mode (LCM) and low noise mode (LNM) versions. 

LCM maximizes efficiency at light-load with controlled output voltage ripple, making the device extremely suitable for battery-powered applications. 

LNM makes the switching frequency constant and minimizes the output voltage ripple overload current range, meeting the specification for noise sensitive applications. 

The EN pin manages the enable/disable function. The typical shutdown current is 2 μA when disabled. When the EN pin is pulled up, the device is enabled and the internal 1.3 ms soft-start takes place. 

Pulse-by-pulse current sensing on both power elements implements effective constant current protection while thermal shutdown prevents thermal run-away.

  • 3.5 V to 38 V operating input voltage
  • Output voltage from 0.85 V to VIN
  • 3.3 V and 5 V fixed output voltage versions
  • 1.5 A DC output current
  • 17 μA operating quiescent current (fixed Vout part numbers)
  • Internal compensation network
  • Two different versions: LCM for high efficiency at light loads and LNM for noise sensitive applications
  • 2 μA shutdown current
  • Internal soft-start
  • Enable function
  • Overvoltage protection
  • Output voltage sequencing
  • Thermal protection
  • SO 8L package
  • Synchronization with external clock for LNM devices