Maxim Integrated Introduces New LED Backlight Driver for Bigger, Higher Resolution Displays

Automotive infotainment system designers can benefit from the new MAX20069 chip that allows the design of bigger, higher-resolution displays at a lower cost and at a smaller resolution size. Integrated with four I2C-controlled, 150 mA LED backlight drivers and four output thin-film transistor liquid crystal display (TFT-LCD) bias, it is designed to provide a smaller footprint than existing similar chips.

Source: Maxim Integrated

Automotive infotainment system designers will soon need to start migrating the standard displays for instrument clusters of 8 into 12.3 inch displays. For this they need precision power solutions, flexibility and smaller resolution size. The MAX20069 chip can provide these requirements.

The chip provides both positive analog supply voltage (PAVVD) and negative analog supply voltage (NAVDD), which are important requirements to support low-temperature polysilicon panels (LTPS) that the industry needs to transition from the now-in-use amorphous silicon displays in order to deliver high-resolution and lower-cost panels.

The MAX20069 supports the high current required by the proposed new generation of displays with 150 mA per channel in the four-channel LED driver. It integrates one buck-boost converter, one boost converter, two gate-driver supplies and a boost/SEPIC converter that can power one to four strings of LEDs in the display backlight.

Some features include:

• Four-output TFT-LCD bias power
  • 2.8 V to 5.5 V input for the TFT-LCD section
  • Integrated 440 kHz or 2.2 MHz boost and buck-boost converters
  • Positive and negative 3 mA gate voltage regulators with adjustable output voltage
  • Flexible resistor-programmable sequencing through the SEQ Pin
  • Undervoltage detection on all outputs
  • Low quiescent current standby mode
• Four-channel LED backlight driver
  • Up to 150 mA current per channel
  • 4.5 V to 42 V input voltage range
  • Integrated boost/SEPIC controller (440 kHz or 2.2 MHz)
  • Dimming ratio 10,000:1 at 200 Hz
  • Adaptive voltage optimization to reduce power dissipation in the LED current sinks
  • Open-string, shorted-LED and short-to-GND diagnostics
• Low EMI
  • Phase-shift dimming of LED strings
  • Spread spectrum on LED driver and TFT
  • Selectable switching frequency
• I²C interface for control and diagnostics
  • Fault indication through the FLTB pin and I²C
• Overload and thermal protection
• -40° C to 105° C ambient temperature operation
• 40-Pin (6 mm x 6 mm) TQFN package with exposed pad

Some applications:

• Automotive central information displays
• Automotive dashboards
• Automotive head-up displays
• Automotive navigation