SBOS571C August 2011 – August 2018 BUF20800-Q1
The VCOM channels of the BUF20800-Q1 can swing to 2V from the positive supply rail while sourcing 50 mA and to 1 V above the negative rail while sinking 50 mA (see Figure 4, typical characteristic Output Voltage vs Output Current). To store the gamma and the VCOM values, an external EEPROM is required. During power-up of the LCD panel, the timing controller can then read the EEPROM and load the values into the BUF20800-Q1 to generate the desired VCOM voltages, as illustrated in Figure 10 and Figure 8. The VCOM channels can be programmed independently from the gamma channels.