Patent · US Expired

Universal serial bus keyboard control circuitry

US7102619B2 · kind B2 · utility

0Cited by
3References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 2, 2003
Grant dateSep 5, 2006
Priority date
Expiry dateFeb 15, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M11/00
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A keyboard control apparatus with a USB interface for use in a notebook computer having a number of keys. In one embodiment, a mapping unit is employed to store a number of key matrix codes corresponding to the keys. In accordance with a clock signal and a start signal, a shift register is capable of generating a reference signal and a number of scan output signals. A key matrix circuit then receives the scan output signals to provide a number of scan input signals. An address generator is used to generate an address signal based on the reference signal and a triggered scan input signal. Thus, a selector can select one key matrix code designated to the address signal from the mapping unit. Additionally, an interface converter further converts the selected key matrix code into a pair of differential signals compliant with the USB specification.

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