Automotive 4-Channel TFT-LCD Power Supply with VCOM buffer

Description

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The MAX25220/MAX25221 is a 4-channel TFT-LCD pow- er IC that provides symmetrical positive AVDD and nega- tive NAVDD supplies as well as VG_ON and VG_OFF gate supplies. In addition, a VCOM buffer with output voltage range above and below ground and a temperature measurement block are integrated (MAX25221).

The device contains non-volatile memory so that the values of all outputs can be calibrated for the lifetime of the device (maximum five times).

Programming is carried out using the built-in I²C interface, which can also be used to read back diagnostic information. A stand-alone mode is also available.

The temperature sensor interface block measures the temperature optionally allowing the VCOM output voltage to be adjusted depending on the measured temperature.

The MAX25220/MAX25221 is available in a TQFN package and operates in the -40°C to 125°C temperature range.

Key Features

• High Integration
  • Synchronous Boost Provides AVDD of 4.2V to 10.5V at up to 200mA
  • NAVDD Inverter Output at up to -200mA
  • 15mA VG_ON Output (7.6V to 20.2V) from 3x Regulated Charge Pump
  • VG_OFF (-18.2V to -5.6V) from Regulated Charge Pump at up to -15mA (charge-pump doubler)/li>
  • Controlled Sequencing during Power-On and Power-Off of All Rails
  • VCOM Output Range +1V to -2.49V in 6.83mV Steps (MAX25221)
  • NTC Input for Temperature Measurement/Compensation (MAX25221)
• Low EMI
  • 420kHz/2.1MHz Switching Frequency with Spread Spectrum
• I²C Control/Diagnostic Interface with FLTB (Interrupt) Output
  • UV diagnostics on All Outputs
• Versatile
  • Non-Volatile Output Voltage Settings on AVDD/NAVDD, VG_ON, VG_OFF, VCOM, and Sequencing
  • Supports Stand-Alone Operation Mode after Programming
  • Compact 5mm x 5mm TQFN32 Package
• ​AECQ100 Grade 1

Applications/Uses

• Central Information Displays
• Infotainment Displays
• Instrument Clusters