BUF22821,pdf(Programmable Gamm

The BUF22821 offers 22 programmable gamma channels, two programmable V_COM 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 V_COM 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 V_COM 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.