The ISL95820 Pulse Width Modulation (PWM) controller IC provides a complete low-cost solution for Intel VR12. 5™ compliant microprocessor core power supplies. It provides the control and protection for a Voltage Regulator (VR). The VR incorporates 3 integrated drivers and can operate in 4-, 3-, 2- or 1-phase configurations. The VR uses a serial control bus to communicate with the CPU and achieve lower cost and smaller board area. The VR utilizes Intersil’s Robust Ripple Regulator R3 Technology™. The R3™ modulator has many advantages compared to traditional modulators, including faster transient response, variable switching frequency in response to load transients, and improved light load efficiency due to diode emulation mode with load-dependent low switching frequency. The ISL95820 has several other key features. It supports either DCR current sensing with a single NTC thermistor for DCR temperature compensation or more precise resistor current sensing if desired; remote voltage sense; programmable VBOOT voltage, IMAX, voltage transition slew rate and switching frequency; adjustable overcurrent protection; and Power-Good signal.


  • Serial data bus
  • SMBus/PMBus/I2C interface with SVID conflict free
  • Configurable 4-, 3-, 2- or 1-phase for the output using three integrated gate drivers
  • Green Hybrid Digital R3™ modulator
  • Excellent transient response
  • Phase shedding with power state selection
  • Diode emulation in single-phase for high light-load efficiency
  • 0.5% system accuracy over-temperature
  • Supports multiple current sensing methods
  • Lossless inductor DCR current sensing
  • Precision resistor current sensing
  • Differential remote voltage sensing
  • Programmable VBOOT voltage at start-up
  • Resistor programmable IMAX, load line, diode emulation, slope compensation, and switching frequency
  • Adaptive body diode conduction time reduction


  • Intel VR125 desktop computers

Product Options

Part Number Part Status Pkg. Type Carrier Type MOQ Buy Sample
Active TQFN Tube 60
Active TQFN Reel 6000
Active TQFN Tube 60
Active TQFN Reel 6000

Documentation & Downloads

Title language Type Format File Size Date
Datasheets & Errata
ISL95820 Datasheet Datasheet PDF 2.39 MB
ISL95820 Data Short Short Form Datasheet PDF 189 KB
User Guides & Manuals
ISL95820EVAL1Z User Guide Manual PDF 1.22 MB
Application Notes & White Papers
Five Easy Steps to Create a Multi-Load Power Solution White Paper PDF 846 KB
AN1684: Nonideality of Ground Application Note PDF 397 KB
AN1681: Grounding Techniques Application Note PDF 509 KB
PA13055 - Data Sheet Specification Change for Listed Intersil Products ISL95820CRTZ* and ISL95820IRTZ* Product Advisory PDF 272 KB