Analog Devices / Maxim Integrated MAX20070 Integrated TFT Power Supplies
Analog Devices MAX20070 Integrated TFT Power Supply and LED Backlight Drivers are designed for automotive TFT-LCD applications. The MAX20070 integrates one buck-boost converter, one boost converter, two gate-driver supplies, and a boost/SEPIC converter that can power one to two strings of LEDs in the display backlight. The source-driver power supplies combine a boost converter and an inverting buck-boost converter capable of generating voltages up to +15V and -15V.
The positive source-driver supply regulation voltage (VPOS) is set by connecting an external resistor-divider on FBP. Connecting the FBP pin to ground sets the regulation voltage (VPOS) to +6.5V. The negative source-driver supply voltage (VNEG) is always tightly regulated to -VPOS within ±50mV. Both the positive and negative source-driver power supplies can deliver up to 100mA. The source-driver supplies use an input voltage from 2.7V to 5.5V to generate the output voltages.
The MAX20070 features a dual-string LED driver that operates off a separate input voltage (VBATT) and can power up to two strings of LEDs with 160mA (max) of current per string. Using one of the seven preset modes controls the startup and shutdown sequences for all power domains and is selectable through a resistor on SEQ. The Analog Devices MAX20070 Integrated TFT Power Supply and LED backlight drivers operate over a -40°C to +105°C ambient temperature range and are available in a 32-pin, 5mm × 5mm TQFN package with an exposed pad.
Features
- Integrates both TFT power supplies and LED backlight driver in one IC, reducing component count
- Alleviates EMI due to spread spectrum on both source driver supplies and LED driver
- 10000:1 dimming ratio at 200Hz dimming frequency
- Available in a 32-Pin (5mm × 5mm) TQFN with an exposed pad for heat dissipation
- Operates over the -40°C to +105°C ambient temperature range
Applications
- Automotive central information displays
- Automotive dashboards
- Automotive head-up displays
- Automotive navigation system