Device for controlling discharge of a charge capacitor in a transponder
US5608406A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 1996 |
| Grant date | Mar 4, 1997 |
| Priority date | — |
| Expiry date | Jun 20, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S13/767
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A transponder device (10) includes a discharge circuit (18) to control the discharge of voltage from a charge capacitor (14). The discharge circuit (18) prevents transmission of a data telegram by the transponder device (10) until a voltage of the charge capacitor (14) reaches a threshold voltage level. The threshold voltage level is sufficient to ensure that a complete transmission of the data telegram is performed. Upon reaching the threshold voltage level, a transponder analog and digital circuit (19) initiates transmission of the data telegram. A control logic circuit (32) activates a counter (36) upon the start of the data telegram transmission. The counter (36) generates a control signal that is used to bypass the discharge circuit in order that the charge capacitor (14) can be connected directly to the transponder analog and digital circuit (19). In this manner, sufficient voltage is available at the beginning and end of the data telegram transmission in order to avoid deterioration of the data telegram transmission signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.