Wide Vin 4.5-26V, 6A, Low Iq, High Current Synchronous Buck Converter with 2-Bit VID

Learn about our Evaluation Kit
Talk to an Engineer or get a Quote
Upgrade to myMPS+

Product Description

The NB681 is a fully integrated, high-frequency, synchronous, rectified, step-down, switch-mode converter with 2-bit VID, especially designed for IMVP8 applications—VCCIO, PRIMCORE, V1.0A, EDRAM, and EOPIO. It offers a very compact solution to achieve a 6 A continuous output current and a 7.5 A peak output current over a wide input supply range.
The NB681 operates at high efficiency over a wide output current load range based on MPS proprietary switching loss reduction technology and internal low Ron power MOSFETs. 
Adaptive constant-on-time (COT) control mode provides fast transient response and eases loop stabilization. The DC auto-tune loop provides good load and line regulation.
To avoid audible noise, NB681 provides low-power mode for power loss saving during the low-power state and ultrasonic mode.
Full protection features include OC limit, OVP, UVP, and thermal shutdown. 
The converter requires a minimal number of external components, and it is available in a QFN 2mm x 3 mm package.


Product Features

  • Wide 4.5 V to 26 V Operating Input Range
  • Output Adjustable by 2-Bit VID
  • Low-Power Mode
  • 25 µA Low Quiescent Current
  • 6 A Continous Output Current
  • 7.5 A Peak Output Current
  • Selectable Ultrasonic Mode
  • Adaptive COT for Fast Transient
  • DC Auto-Tune Loop
  • Stable with POSCAP and Ceramic Capacitors
  • 1% Reference Voltage
  • Internal Soft Start
  • Output Discharge
  • OCL, OVP, UVP, and Thermal Shutdown,
  • Latch-Off Reset via EN or Power Cycle
  • QFN 2mm x 3mm Package


  • fsw (max) (kHz)750
  • Vin (min) (V)4.5
  • Vin (max) (V)26
  • Iout (max) (A)6
  • Isw Limit (typ) (A)7.6
  • Vfb (typ) (V)0.6
  • Iq (typ) (mA)0.15
  • Regulated Outputs1
  • Vout (max) (V)1.2
  • Vout (min) (V)0
  • GradeCatalog
  • PackageQFN-13 (2x3)
  • Control ModeCOT
  • Common FeaturesLight-Load Efficiency, Power Good, Synchronous Rectification
  • Special FeaturesOutput Adjustable by 2-Bit VID, Output Discharge, Ultrasonic Mode

Reference Materials