HD66781 Datasheet, PDF (23/196 Pages) Renesas Technology Corp – 720-channel Source Driver for a-Si TFT/Low Temperature Poly-Si TFT Panels with 262,144-color display RAM

HD66781
Preliminary
(6) Timing generator
Timing generator generates a timing signal for the operation of internal circuits such as GRAM. The
timing for display operation such as RAM read and the internal operation timing such as access from MPU
are generated in a way to avoid mutual interfere. Also the signals interfacing with gate driver/power supply
IC (M, FLM, CL1/SFTCLK1, SFTCLK2, EQ, DCCLK, and DISPTMG) are generated.
(7) Oscillation Circuit (OSC)
The HD66781 generates R-C oscillation simply by placing an external oscillation-resistor between the
OSC1 and OSC2 pins. The oscillation frequency is changeable with the value of external resistor. Adjust
oscillation frequency in accordance to an operation voltage, display size, and frame frequency. During the
standby mode, the R-C oscillation is halted to reduce power consumption. For details, see “Oscillation
Circuit” (p.173).
(8) Liquid Crystal Display Driver Circuit
The LCD driver circuit consists of a 720-output source driver (S1 ~ S720). Display pattern data are latched
when 720-bit data arrive. The latched data controls the source driver and generates drive waveforms. The
shift direction of 720-bit output from source driver is changeable with SS bit. Select an appropriate shift
direction for the assembly.
(9) Gate driver/power supply IC interfacing circuit
Gate driver/power supply IC interfacing circuit is a serial interface circuit to interface with the HD66783
and the HD667P21. When making settings for instructions to the HD66783 or the HD667P21 though the
HD66781, values set in the register of HD66781 are transferred through this serial interface circuit. The
transfer starts by making a serial transfer ENABLE setting. Both transfer of instruction to the
HD66783/HD667P21 and read out from the HD66781 are impossible during standby mode. For details,
see “Gate Driver/Power Supply IC interface control” (p.70).
(10) Internal Logic Power Supply Regulator
Internal logic power supply regulator generates power supply VDD for the internal logic.
Rev.0.5, July.31.2003, page 23 of 196