LSI Device including a liquid crystal display drive

Claim 1

In a circuit for driving a liquid crystal display, said liquid crystal display including segment electrodes and a counter electrode, said circuit including a segment electrode selection signal generator for driving selected ones of said segment electrodes of said liquid crystal display, a liquid crystal enable voltage generator for developing a plurality of voltages to drive said segment electrode selection signal generator and for developing a further output signal, a counter electrode selection signal generator responsive to said further output signal for developing a voltage waveform and applying said voltage waveform to said counter electrode, and control means for developing a control signal and for developing driving signals for driving said liquid crystal enable voltage generator and said counter electrode selection signal generator, the improvement comprising: a plurality of bleeder resistors for generating said plurality of voltages from said enable voltage generator; open-circuiting means responsive to said control signal from said control means and connected in series with said bleeder resistors for open-circuiting a current path through said bleeder resistors and for constraining the plurality of voltages to a substantially identical level; and clamping means responsive to said control signal from said control means for containing the voltage waveform being applied to said counter electrode by said counter electrode selection signal generation to a voltage which is substantially equal to said substantially identical level.