KTD3136 is the ideal power solution for LED backlighting in medium to large size LCD panels. It is a highly integrated step-up DC-DC converter operating with an input voltage from 2.7V to 5.5V, accommodating 1-cell lithium ion batteries or 5V supply. It includes a high voltage power NMOS, as well as three current sinks, resulting in a simpler and smaller solution with fewer external components. High switching frequency allows the use of a smaller inductor and capacitor.

Each of the three regulated current sinks can regulate up to 29.8mA in backlight mode. With a maximum of 32V at the output of the step-up converter, each string can connect up to 8-LED in series for a 24-LED application.

KTD3136 is equipped with I2C interface for various controls. For additional flexibility, PWM dimming with a wide range frequency and duty cycle is included to support Content Adaptive Brightness Control (CABC).

Various protection features are built into KTD3136, including cycle-by-cycle inductor current limit protection, output over-voltage protection, LED fault (open or short) protection, and thermal shutdown protection.

KTD3136 is available in a RoHS-compliant 12-ball 1.22mm x 1.67mm WLCSP or a 16-lead 3mm x 3mm x 0.75mm Thin-QFN package.


  • Wide input range: 2.7V~5.5V
  • High efficiency step-up 3-Channel LED driver
  • 3-Ch current sinks, up to 8-LEDs per string
    • Up to 29.8mA/Ch
    • +/-0.6% current matching at 20.2mA
    • +/-1.5% current accuracy at 20.2mA
  • I2C/PWM dual dimming control scheme
    • 11-bit I2C exponential or linear mapping with programmable transition ramp time
    • Wide range PWM dimming with programmable transition ramp time
      • 100Hz to 100kHz frequency
      • 0.2% to 100% duty cycle at 20kHz
  • Programmable current sink turn on/off ramp time and shape
  • Selectable boost converter switching frequency 1MHz or 500kHz with 20% shift up option
  • Programmable input PWM hysteresis to minimize jitter at low PWM duty cycle
  • Programmable OVP (25.9V/32V) and current limit (2.6A/1.8A)
  • LED open/short protection
  • Status reporting through I2C interface


Smartphone/Tablet Backlight

Packaging Information

Package Dimensions Bumps Package Code
TQFN33-16 3.00mm x 3.00mm x 0.75mm 16 FJ
WLCSP34-12 1.22mm x 1.67mm x 0.62mm 12 US


Vin (min)  Vin (max)  Number of LEDs/ Channels LED Channels Total Number of LEDs Brightness Control Switching Frequency (MHz) Current per Channel (Max) Output OVP
2.7V 5.5V 8 2 16 I2C and/or PWM 1.0/0.5 29.8mA 25.9V/32V

Technical Documentation

Description Documents Type
Package Outline DrawingWLCSP34-12 US PODPDF


Part Number Marking Operating Temperature Package
KTD3136EFJ-TR LKYYZ -40°C to +85°C TQFN33-16
Purchase Options
Buy from Digi-Key
Buy from Mouser