Patent · US Expired

Damping modulation circuit for a full-duplex transponder

US6167236A · kind A · utility

92Cited by

13References

20Claims

0Family size

Assignee

TEXAS INSTRUMENTS DEUTSCHLAND GMBH · DE

Inventors

Ulrich Kaiser · Warstein, DE
Wolfgang Steinhagen · Moosburg an der Isar, DE

Key dates

Filing date	Jan 31, 1997
Grant date	Dec 26, 2000
Priority date	—
Expiry date	Jan 31, 2017

Classification

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

Abstract

An improved damping modulation circuit (140) for a transponder (14) receives energy transmitted from a transmitter/receiver antenna (16) to produce a unique recognition signal in the transponder. The improved damping modulation circuit (140) includes a high fieldstrength circuit (152, 160, 174) that protects full-duplex transponder (14) from over-voltage through the use of voltage limiters (132), while still providing power to transponder (14). Low fieldstrength circuit (152) activates only minimal circuitry to provide the highest possible amount of power to full-duplex transponder (14). Medium fieldstrength circuit (152, 160) increases the fieldstrength in full-duplex transponder (14) for establishing a sufficient amount of current flow for proper modulation using only a medium amount of transponder (14) circuit elements.

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