The KTB2140 is a PWM controller that integrates all the circuitry required to design a smart and efficient converter for PoE and telecom small and mid-powered applications.

KTB2140 features a programmable oscillator for the switching frequency, adjustable slope compensation, dual low-side drivers with programmable dead time, programmable soft-start, soft-stop, programmable frequency dithering, and maximum duty limit.

An internal high-voltage linear regulator allows the device to start up with a minimum number of external components. There are dual low side gate drivers that are mainly for active clamp forward application. When the second driver is not used in low power flyback converters, it can be floating.

The KTB2140 device embeds a set of protections that enable the design of a self-protected converter. It also targets high efficiency conversion at a wide range of loads.


  • Fully supports IEEE® Std. 802.3bt
  • PWM peak current mode controller
  • Dual low side gate driver
  • High efficiency topologies:
    • Flyback, Forward
    • Flyback with synchronous rectification
    • Flyback with active clamp
    • Forward with active clamp
    • Wide VIN Range: 8V to 80V
  • >1.5A Output Gate Drive Capability
  • Programmable fixed frequency up to 1MHz
  • Integrated Short-Circuit Protection.
  • Programmable Soft Start Time
  • Programmable dead time between G1 and G2
  • Programmable slope compensation
  • Internal pull-up resistor in feedback for optocoupler and isolated connection
  • Over current, OV/UVLO, and thermal Protection
  • Programmable Frequency Dithering for Low EMI Spread-Spectrum Operation
  • Synchronous External Clock
  • Soft turn off
  • Maximum duty cycle limit
  • Internal high voltage start-up regulator
  • -40°C to +125°C Junction Temperature Range
  • Small 3mmx3mm WQFN Package


  • PoE Powered Devices
  • Up to 200 Watt SMPS
  • Voice over IP (VoIP) Phones
  • Lighting and High-Power Wireless Data Systems
  • Wireless LAN Access Points, WiMAX Terminals
  • Point-of-sale (POS) Terminals, RFID Terminals
  • Thin Client and Notebook Computers
  • Fiber-to-the-home (FTTH) Terminals

Packaging Information

Package Dimensions Bumps Package Code
WQFN33-16 3.00mm x 3.00mm x 0.75mm 16 WQFN

Technical Documentation

Description Documents Type


Purchase Options Coming Soon