XX-XXXX; Rev 0; 4/06 14 Programmable Gamma Reference Buffers with 4 Static References for TFT-LCD Displays The MAX9590 provides 14 programmable voltage references and 4 static voltage references for gamma correction in TFT-LCD displays. Two register banks are provided to store two sets of gamma reference values. Gamma values are programmed into the banks through the I2C* interface and the outputs can switch between values in 0.5µs. The 14 programmable reference voltages are divided evenly into seven upper and seven lower voltages for the upper and lower gamma curves of LCD column drivers. Each gamma reference voltage has an 8-bit DAC and isolation buffer associated with it to ensure stable operation. Therefore, the reference voltages remain stable without synchronizing to the LCD horizontal timing. In addition, each buffer is able to provide a high current that further ensures a stable voltage when critical levels and patterns are displayed. The 14 programmable buffers wake-up in high-impedance state until the registers are programmed. This protects the LCD system from high transient currents during the startup phase. The MAX9590 is available in a 38-pin TQFN package and is specified for operation over the -40°C to +85°C temperature range. Features 14 Programmable Reference Voltages 4 Static Reference Voltages Independent DACs with 8-Bit Resolution Two Register Banks for Two Sets of Gamma Values Fast Switching between Gamma Values 16.5V (max) Operating Voltage Output Swing within 150mV of Rails Peak Current Greater than 200mA Output Channels Tri-Stated During Wake-Up Block Diagram REFU_H OUT_REFU_H OUT1 AVDD BANK A MEMORY (HIGH) OUT2 DVDD OUT3 GND CAP OUT4 BANK B MEMORY (HIGH) OUT5 Applications OUT6 TFT-LCD Displays OUT7 Industrial Reference Voltage Generators REFU_L OUT_REFU_L BANK_SEL REFL_H OUT_REFL_H Ordering Information PART MAX9590ETU+ TEMP RANGE PIN-PACKAGE -40°C to +85°C 38 TQFN (5mm x 7mm) OUT8 OUT9 PKG CODE BANK A MEMORY (LOW) OUT10 T3857-1 OUT11 +Denotes lead-free package. OUT12 BANK B MEMORY (LOW) OUT13 OUT14 *Purchase of I2C components from Maxim Integrated Products, Inc. or one of its sublicensed Associated Companies, conveys a license under the Philips I2C Patent Rights to use these components in an I2C system, provided that the system conforms to the I2C Standard Specification as defined by Philips. REFL_L SCL SDA A0 OUT_REFL_L I2C INTERFACE MAX9590 STD_REG ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX9590 General Description