Operational amplifier circuit, driving circuit and driving method

• Main Author: ISHIYAMA HISANOBU
• Format: Patent
• Language: English
• Published: 18.04.2006
• Subjects: ADVERTISING; AMPLIFIERS; ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICESUSING STATIC MEANS TO PRESENT VARIABLE INFORMATION; BASIC ELECTRONIC CIRCUITRY; CRYPTOGRAPHY; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; DISPLAY; EDUCATION; ELECTRICITY; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; PULSE TECHNIQUE; SEALS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

In a period T 1 (positive polarity) in which a voltage level of a counter electrode VCOM becomes VC 1 , a data line is driven using P-type operational amplifier OP 1 having P-type driving transistor, while in a period T 2 (negative polarity) in which VCOM becomes VC 2 , the data line is driven using N-type operational amplifier OP 2 having N-type driving transistor. An output of a selection circuit for the operational amplifiers OP 1 , OP 2 is set to the high impedance state when VCOM is changed over. At the time of driving the operational amplifier OP 1 , a current which flows in current sources of the operational amplifier OP 2 is cut off, while at the time of driving the operational amplifier OP 2 , a current which flows in current sources of the operational amplifier OP 1 is cut off. In the period before the operational amplifiers OP 1 , OP 2 are driven, the driving transistors of the operational amplifiers OP 1 , OP 2 are turned off. The voltage level of the data line can be changed before driving by positively utilizing the parasitic capacitance between the counter electrode and data line.