Circuit arrangement for load regulation in the receive path of a transponder

• US 7,317,307 B2
• Filed: 03/17/2005
• Issued: 01/08/2008
• Est. Priority Date: 03/17/2004
• Status: Expired due to Fees

• Current Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Original Assignee: Atmel Germany GmbH (Microchip Technology Incorporated)
• Inventors: Fischer, Martin
• Primary Examiner(s): NGUYEN, MATTHEW VAN
• Application Number:
  US11/081,565
• Publication Number:
  US 20050208915A1
• Time in Patent Office: 1,027 Days
• Field of Search: 323/268, 323/270, 323/299, 323/303, 323/312, 323/315, 327538-541, 327/543, 455/270, 455/280, 455/292, 455/334, 455/338, 455/343.1
• US Class Current: 323/315
• CPC Class Codes: G06K 19/0707 the arrangement being capable of collecting energy from external energy sources, e.g. thermocouples, vibration, electromagnetic radiation G06K19/0702 takes precedence
• CPC Class Codes: G06K 19/0712 the arrangement being capable of triggering distinct operating modes or functions dependent on the strength of an energy or interrogation field in the proximity of the record carrier active means for hindering electromagnetic reading or writing G06K19/07336
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs

Abstract

A circuit arrangement for load regulation of circuit components is arranged in a receive path of a transponder, having an input path through which a first voltage signal can be tapped, having a voltage sensor arranged in the input path for measuring the first voltage signal, having at least one output path through which a discharge current signal can be tapped, having at least one controllable auxiliary current source arranged between the input path and the output path to provide the at least one discharge current signal, the control side of the auxiliary current source being connected to an output of the voltage sensor such that the value of the discharge current signal increases exponentially with increasing voltage of the first voltage signal.

Claims

1. A circuit arrangement for load regulation of circuit components arranged in a receive path of a transponder, the circuit arrangement comprising:

an input path through which a first voltage signal can be tapped;

a voltage sensor arranged in the input path for measuring the first voltage signal;

at least one output path through which a discharge current signal can be tapped; and

at least one controllable auxiliary current source being arranged between the input path and the output path to provide the discharge current signal such that a value of the discharge current signal increases exponentially with increasing voltage of the first voltage signal, a control side of the auxiliary current source being connected to an output of the voltage sensor.

2. The circuit arrangement according to claim 1, wherein the auxiliary current source is a current sink for providing a discharge current.

3. The circuit arrangement according to claim 1, wherein the input path is arranged between a first input connection for coupling the input potential and a second connection having a supply potential, and wherein each of the at least one output paths is connected to an output connection of the circuit arrangement through which the discharge current signal can be tapped.

4. The circuit arrangement according to claim 3, wherein the voltage sensor has at least one first diode that is connected in a forward direction relative to the first input connection.

5. The circuit arrangement according to claim 1, wherein the auxiliary current source has at least one current mirror circuit that is arranged on an input side of the input path and that is connected on an output side with an output connection of the circuit arrangement.

6. The circuit arrangement according to claim 5, wherein at least one second diode of the voltage sensor is formed of a diode of the current mirror circuit and is connected in series with the other diodes of the voltage sensor.

7. The circuit arrangement according to claim 6, wherein at least one of the diodes of the voltage sensor and/or at least one of the diodes of the auxiliary current source is a pn diode, a MOS diode, or a Schottky diode.

8. The circuit arrangement according to claim 1, wherein the voltage sensor has three diodes connected in series to one another.

9. The circuit arrangement according to claim 1, wherein transistors of the voltage sensor and/or transistors of the auxiliary current source are MOSFET transistors or CMOS transistors.

10. The circuit arrangement according to claim 3, wherein the supply potential is a reference potential or a reference ground potential.