| abstract |
A liquid crystal device drive circuit has a positive power supply terminal, a negative power supply terminal, a ground terminal, a control input and an output terminal for connection to a liquid crystal device incorporating a composition having smectic-A properties. The circuit has a first controllable-device for coupling the positive power supply terminal to an output terminal, a second controllable device for coupling the negative power supply terminal to the output termmal and a third controllable device for coupling the ground terminal to the output terminal, the first second and third controllable devices being controllable in accordance with the control input. |