Low Output-Offset Variation S/H Circuits for An LCD Segment Driver IC Achieving Wide Signal Frequency Bandwidth

This paper describes two types of S/H circuits of low output-offset variation for Liquid-Crystal-Display segment driver ICs. The basic ideas for reducing the output-offset variation without narrowing the signal frequency bandwidth are to improve the timing of the sampling pulses applied to analog MOS switches and to prevent channel charge injection[1][2] onto a storage capacitor when the switches turn off. Output-offset standard deviation ranges from 8.7 mV_rms to 15.6 mV_rms depending on the input voltage. The measured -3 dB bandwidth is 7.2 MHz. An integral nonlinearity of 0.21 % and offset error of 76 mV have been accomplished within the input/output range from 1.5 V to 11.5 V.