Intersil is addressing the problem with its ISL76534 14-channel gamma buffers IC, which it claims as the lowest-power part offering such functionality. The automotive-grade part ensures consistent brightness and colour matching across all LCD panels used in a vehicle. The ISL76534 is suitable for next generation LCDs designed for infotainment displays, advanced driver assistance system (ADAS) smart mirrors and instrument cluster displays.
The IC provides one Vcom and 14 gamma channels with 10-bit resolution for fine-tuning the gamma curve, avoiding panels that appear either bleached-out or too dark. It stores parameters in on-chip EEPROM, with 10,000 writes cycles and 20-year data retention at 105C. It offers flexibility in power-rail bring-up sequencing; and a 75 dB PSRR to keep power supply noise from reaching then buffer and appearing as visible interference. It uses 56.6 mW.
The ISL76534 contains an I ²C programmable, 10-bit, 14-channel gamma reference voltage generator with buffered outputs, a 10-bit programmable VCOM calibrator, a high output current VCOM amplifier, and internal EEPROM to store all reference voltage data.
In a super thin (height = 0.4mm maximum) 28 lead 4 x 5 mm X2QFN thermally enhanced package, specified for operation across the ambient temperature range of -40°C to +105°C, the device is priced at $1.99 (1000). An evaluation board is $116.