Title:
DRIVING CIRCUIT FOR LIQUID CRYSTAL DISPLAY DEVICE
Document Type and Number:
Japanese Patent JP3226567
Kind Code:
B2
Abstract:
PURPOSE: To obtain the output circuit of a liquid crystal driver which can supply liquid crystal with a stable liquid crystal driver output voltage having no reference voltage different from an output voltage while the liquid crystal driver output voltage speedily reaches an optionally selected driving reference voltage by using an operational amplifier in a voltage-follower connection state.
CONSTITUTION: This driving circuit is equipped with the operational amplifier OP1 connected in the voltage-follower state to a CMOS transfer switch which sends the driving reference voltage selected by CMOS transfer switch groups SW1-SW7 to a driver output terminal. For example, a driving reference voltage VR0 is outputted as an initial value to the driver output O first and then a driving reference voltage VR3 is applied to the liquid crystal. The switches SW2 and SW4 are turned ON by holding control signals A and B at high level. At the same time, the operational amplifier OIP1 is put in operation with operation control signals Z and Z of the operational amplifier OP1. Consequently, a load capacitor CL is charged speedily through the amplifying operation of a differential amplifier OP1 and the driver output O speedily reaches the driving reference voltage VR3.
Inventors:
Hiroshi Shiba
Tadashi Saito
Yasuhiro Miyahara
Tadashi Saito
Yasuhiro Miyahara
Application Number:
JP18797291A
Publication Date:
November 05, 2001
Filing Date:
July 29, 1991
Export Citation:
Assignee:
NEC
NC Microsystem Co., Ltd.
NC Microsystem Co., Ltd.
International Classes:
G02F1/133; G09G3/20; G09G3/36; (IPC1-7): G09G3/36; G02F1/133; G09G3/20
Domestic Patent References:
| JP28813A | ||||
| JP377913A | ||||
| JP1144299A |
Attorney, Agent or Firm:
Naoki Kyomoto (2 outside)