Wide Vin 5.5-26V, Low Iq, High Current, Fixed 5V-8A Synchronous Buck Converter with 100mA LDO



The NB679 is a fully integrated, high-frequency, synchronous, rectified, step-down switch-mode converter with a fixed 5 V output. It offers a very compact solution to achieve 8 A continuous output current and 10 A peak output current over a wide input supply range with excellent load and line regulation. 
The NB679 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.
NB679 provides a fixed 5 V LDO, which can be used to power the external peripheries. 
Full protection features include OC limit, OVP, UVP, and thermal shutdown. 
The converter requires a minimum number of external components and is available in QFN 2mm x 3mm package.



  • Wide 5.5 V to 26 V Operating Input Range
  • Fixed 5 V Vout
  • Supports 5.5 V-5 V
  • Ultrasonic Mode with Fs over 25 kHz
  • 100 μA Low Quiescent Current
  • 8 A Continous Output Current
  • 10 A Peak Output Current
  • Adaptive COT for Fast Transient
  • DC Auto-Tune Loop for Load Regulation
  • Stable with POSCAP and Ceramic Output Capacitors
  • Built-In 5 V, 100 mA LDO with Switch Over
  • 1% Reference Voltage
  • Internal Soft Start
  • Output Discharge
  • 700 kHZ Switching Frequency
  • OCP, OVP, UVP, and Thermal Shutdown.
  • Latch-Off Reset via EN or Power Cycle
  • QFN-12 (2mm x 3mm) Package


  • fsw (max) (kHz)700
  • 最小输入电压5.5
  • Vin (max) (V)26
  • Iout (max) (A)8
  • Isw Limit (typ) (A)11
  • Vfb (V)5
  • Iq (typ) (mA)0.11
  • 额定输出1
  • Vout (max) (V)5
  • Vout (min) (V)5
  • GradeCatalog
  • PackageQFN-12 (2x3)
  • Control ModeCOT
  • Common FeaturesLight-Load Efficiency, Power Good, Synchronous Rectification
  • Special FeaturesOutput Discharge, Ultrasonic Mode