22-CH Gamma-Voltage Generator and Vcom Calibrator with Integrated Two-Bank Memory

The BUF22821 offers 22 programmable gamma channels, two programmable VCOM channels, and two static gamma channels. It is ideal for the new 10-bit source drivers that require 22 gamma channels.

The final gamma and VCOM values can be stored in the on-chip, nonvolatile memory. To allow for programming errors or liquid crystal display (LCD) panel rework, the BUF22821 supports up to 16 write operations to the on-chip memory. The BUF22821 has two separate banks of memory, allowing simultaneous storage of two different gamma curves to facilitate switching between gamma curves.

All gamma and VCOM channels offer a rail-to-rail output that typically swings to within 100mV of either supply rail with a 10mA load. All channels are programmed using an I2C interface that supports standard operations up to 400kHz and high-speed data transfers up to 3.4MHz.

The BUF22821 is manufactured using Texas Instruments' proprietary, state-of-the-art, high-voltage CMOS process. This process offers very dense logic and high supply voltage operation of up to 20V. The BUF22821 is offered in a HTSSOP-38 PowerPAD™ package. It is specified from -40°C to +85°C.