Patent · US Active

Power source circuits for driving liquid crystal displays

US8022748B2 · kind B2 · utility

0Cited by
3References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 12, 2008
Grant dateSep 20, 2011
Priority date
Expiry dateMay 24, 2030

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02M3/07
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

This invention is suitable for use in the field of integrated circuits. It provides a type of power source circuit. Said power source circuit includes: a charge pump circuit used to operate the charge pump to produce driving voltages; a first control circuit, used in the closed-loop control of said charge pump circuit to produce a positive high voltage; a bias-ratio circuit, used with the positive high voltage and the zero-potential voltage produced by the first control circuit to produce a positive sub-high voltage and a lowest positive high voltage; and a second control circuit, used in accordance with the positive sub-high voltage and the lowest positive high voltage produced by said bias-ratio circuit in the closed-loop control of said charge pump circuit to produce a negative high voltage. Using this invention, the system contains no voltage higher than the liquid crystal's driving voltages, and also does not contain any lower negative voltage than the liquid crystal's highest negative driving voltage, thereby reducing the circuit's electrical consumption.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.