INTEGRATED CIRCUIT FOR ARITHMETIC OPERATION AND DISPLAY

摘要

The control circuit produces a control signal which is at logic 'I' during display and at logic 'O' during arithmetic operation. The boosting circuit receives the control signal to double a power source voltage from a source to produce a voltage when the signal is at 'I'. The drive circuit receives a control signal from the control circuit and produces a drives output of a waveform suitable for driving the LCD, using the boosted voltage when the signal is at 'I' representing a display period. When the signal is at 'O' representing an arithmetic operation period, the drive circuit produces an output having a value Vss=0 so as not to drive the LCD.