LED Backlight Driver with Integrated LCD Bias Delivers Smallest Footprint for Larger Automotive Displays

Published  August 23, 2018   0
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LED Backlight Driver with Integrated LCD Bias Delivers Smallest Footprint for Larger Automotive Displays

Maxim’s new IC MAX20069, which integrates four I2C-controlled, 150mA LED backlight drivers and a four-output thin-film-transistor liquid-crystal display (TFT-LCD) bias in a single chip, allows automotive infotainment designers to upgrade to bigger, higher resolution displays with greater ease, reduced cost and smaller solution size. The chip can reduce design footprint up to one-third compared to the other available alternate solutions.

 

The size of automotive displays are increasing over time as vehicle manufacturers lure buyers with greater information and entertainment options; a vehicle Market research suggests a 39 percent compound annual growth ratefor the 8-inch display market in vehicle instrument clusters, center stack and heads-up display systems. Instrument clusters are expected to migrate to 12.3-inch displays soon. Thus the automotive infotainment system designers will require power solutions with precision, flexibility and small overall solution size to meet increasingly complex system requirements.

 

MAX20069 supports larger screen sizes and higher resolution by providing positive analog supply voltage (PAVVD) and negative analog supply voltage (NAVDD), both of which are required for low-temperature polysilicon panels (LTPS)that deliver higher resolution and lower cost than amorphous silicon panels now currently in use. The IC also supports the high currents that next-generation displays require, with 150mA per channel in the four-channel LED driver for 8-inch or larger displays and higher resolutions. MAX20069 operates over the minus 40-degree Celsius to 105-degree Celsius ambient temperature range and is available in a 6mm x 6mm TQFN package.

 

Key Advantages

  • High Integration: Reduces design footprint, providing TFT-LCD biaswith four rails plus four 150mA LED backlight drivers.
    • Single board supports panels from multiple manufacturers through a resistor or I2C programmable sequencing to further reduce solution size
    • Utilizes 25 percent of the microcontroller (MCU) register bits versus closest competitor’s solution, eliminating the need for a more powerful and costlier MCU in display designs
  • Performance: Delivers twice the dimming ratio compared to the closest competitor’s offering, maintaining panel readability during transition to different light conditions; MAX20069 supports increased resolution through a 10,000:1 pulse-width modulation (PWM) dimming ratio at 200Hz
  • Safety and Built-in Diagnostics: An easy-to-use I2C interface quickly pinpoints problems, directing the microcontroller to adjust to conditions or alert the driver of a failure
  • Electromagnetic Interference(EMI) Mitigation: 2.2MHz switching frequency, spread spectrum and phase-shift capabilities help mitigate interference and emissions