Internal 45V MOSFET Switching Regulator IC for Capacitor Charge Boost Converter

Data Sheet


  • Current Mode Control
  • External Clock Synchronization
  • Operating Voltage Range (4.5V to 40V)
  • Switching Current (1.75A min.)
  • PWM Control
  • Built-in Compensation Circuit
  • Correspond to Ceramic Capacitor (MLCC)
  • Oscillating Frequency (2MHz typ. (C ver.))
  • Soft Start Function (10ms typ.)
  • UVLO (Under Voltage Lockout)
  • Over Current Protection (Pulse-by-Pulse type)
  • Thermal Shutdown Protection
  • Standby Function
  • Package Outline (SOT-89-5-2)

General Description

The NJW4138 is a step up switching regulator with 45V, 1.75A power MOSFET. The NJW4138 has a current mode control, a high frequency oscillating over a wide operating voltage range and an internal phase compensation circuit, so that it provides boost applications with a few external parts. The NJW4138 has built-in overcurrent protection for Pulse-by-Pulse, it is suitable for charging the backup capacitor.


  • Capacitor Charge
  • Power supply for VFD
  • Low power boost application

Package Information

Part NumberPackage OutlinePinsMaterial Declaration (RoHS/Halogen)Terminal FinishWeight(mg) (Reference)Reflow solderingFlow solderingIron solderingPacking ConditionMSLSolder Foot Print
NJW4138U2-CSOT-89-5-25-Sn2Bi61YesYesYesNon dry pack1

Sample & Buy

Part NumberPackagesStatusPacking SpecificationSampleBuy
NJW4138U2-CSOT-89-5-2(Active)Contact UsStock Check