Patent · US Expired

Low voltage speech synthesis system with pulse width digital-to-analog converter

US4357489A · kind A · utility

11Cited by
7References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 4, 1980
Grant dateNov 2, 1982
Priority date
Expiry dateFeb 4, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG10L13/047
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

Integrated circuit speech synthesis system utilizing complementary metal-insulator-semiconductor technology to achieve low voltage operation, wherein a pluse width modulated digital-to-analog converter is employed to provide for accurate conversion of digital signals into analog signals even though the low voltage operation prohibits the large voltage swings normally required for digital-to-analog converter circuitry. The speech synthesis system includes a linear predictive filter as a speech synthesizer which utilizes coded reflection coefficients to produce digital signals representative of human speech. A microprocessor controls the access of digitized speech data which is stored in a memory. The speech synthesizer and microprocessor along with the pulse width modulated digital-to-analog converter are implemented in complementary metal-insulator-semiconductor technology. The system also includes a speaker for generating audible sounds in the form of synthesized human speech from the analog signals provided by the digital-to-analog converter.

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