New Industry Products

16-Channel LED Backlighting Driver with Integrated Current Sinks for HDR Displays

September 24, 2019 by Paul Shepard

The iW7038 LED driver for LCD backlighting from Dialog Semiconductor integrates 16 precision current sinks with advanced digital control technology to improve brightness control in High Dynamic Range displays (HDR).  The digital control block uses Dialog's BroadLED™ adaptive switch technology, improving thermal performance by optimizing the voltage drop across each LED string, while enabling precision matching with unbinned LEDs.

The iW7038 also uses Dialog's patented AnyMode™ dimming, which offers comprehensive, simple and flexible options to improve HDR display picture quality. It allows continuous pwm signals or very narrow pwm burst signals that are fully synchronized to the video frame at the same or higher frequency.

The pwm duty cycle can be updated in each video frame and with user-configurable tail or head delays. This provides more options to reduce motion blur and improve the contrast ratio.

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AnyMode dimming also helps reduce motion blur caused by the human visual system (HVS) by generating high intensity, short duration pwm pulses. This results in faster fade out and reduces the physiological afterimage effects of the HVS, important for automobile dashboard displays.

Summary of specifications and features:

  • 16-channel LED driver with internal MOSFET current sinks
  • 55V maximum output voltage per channel
  • Patented BroadLED™ adaptive switch mode technology for high current matching at maximum efficiency
    • Reduces power dissipation requirements
    • Enables use of cheaper, loosely binned LED arrays for lower BOM cost
  • Flexible input supply voltage rating: 12V (9V-16V)
  • AnyMode™ comprehensive dimming control improves picture quality
    • 13-bit pwm dimming or 11-bit global dimming to improve contrast ratio
    • Head, tail, center mode pwm alignments to reduce motion blur
    • 9-bit independent analog dimming
    • PWM dimming range: 0% to 99.9%
    • Programmable slew rate - better EMI control
  • Comprehensive protection features:
    • Individual LED short protection
    • Channel-to-channel short protection
    • Current sink MOSFET drain-to-source short protection
    • Current sense resistor short protection
    • Microcontroller interrupt interface
    • LED open-fault detection
    • Over-temperature protection
  • External current sense resistors - maximum flexibility for current requirements
    • 200mA per channel max; supports 2-channel grouping
  • SPI daisy-chain interface simplifies design when supporting more than 16 LED strings
  • 3 SPI communication protection modes in one LED driver
  • Internal PLL ensures jitter-free operation even with noisy VSYNC signal