Patent · US Expired

Supply voltage processing circuit and a data carrier with a supply voltage processing unit

US5874829A · kind A · utility

7Cited by
4References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 24, 1997
Grant dateFeb 23, 1999
Priority date
Expiry dateJun 24, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K19/0723
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Two parallel regulator stages, each comprising a transistor (T1, T2, respectively), are provided. The transistor (T2) forms part of the indirect parallel regulator stage and acts directly on the rectifier. It is capable of taking up comparatively large currents and hence is comparatively slow. The transistor (T1) forms part of the direct regulator stage and operates in parallel with the sustaining capacitor. Because of the coarse control provided by the transistor (T2), it need take up small currents only and can hence have a very fast control behavior. Because of the coarse control by the transistor (T2), the alternating voltage on the antenna terminals (LA and LB) quickly breaks down when the RF signal is interrupted; consequently, the transmission rate can be increased in the case of pause interval modulation. Static discharges are also dissipated by the transistor (T2), so that no additional protective circuitry is required for this purpose.

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