Detector and a voltage converter

• US 10,132,843 B2
• Filed: 07/11/2013
• Issued: 11/20/2018
• Est. Priority Date: 07/11/2013
• Status: Expired due to Fees

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Krainer, Siegfried, Marbler, Wolfgang, Granig, Wolfgang
• Primary Examiner(s): Patel, Paresh
• Application Number:
  US13/939,646
• Publication Number:
  US 20150016163A1
• Time in Patent Office: 1,958 Days
• Field of Search: None
• CPC Class Codes: G01R 15/205 using magneto-resistance devices, e.g. field plates
• CPC Class Codes: G01R 19/0092 measuring current only all subgroups of G01R19/00 take precedence
• CPC Class Codes: G01R 33/09 Magnetoresistive devices
• CPC Class Codes: H02M 1/0009 Devices or circuits for detecting current in a converter
• CPC Class Codes: H02M 3/33592 having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
• CPC Class Codes: H10N 50/80 Constructional details
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A detector for detecting an occurrence of a current strength of interest of a current of a signal to be sensed includes a magnetoresistive structure and a detection unit. The magnetoresistive structure varies a resistance depending on a magnetic field caused by the current of the signal to be sensed. Further, the detection unit generates and provides a current detection signal indicating an occurrence of the current strength of interest based on a detected magnitude of the varying resistance of the magnetoresistive structure.

Claims

1. A detection system for detecting an occurrence of a zero current of a current signal to be sensed, the detection system comprising:

a magnetoresistive structure configured to vary a resistance depending on a magnetic field caused by the current signal to be sensed; and

a detector configured to;

generate and provide a current detection signal indicating zero current of the current signal based on a detected magnitude of the varying resistance of the magnetoresistive structure and an adjustment signal; and

generate the adjustment signal based on the current detection signal and a sensitivity of the magnetoresistive structure, wherein the current detection signal comprises a peak, a pulse, a rising signal edge or a falling signal edge at a time when the detected magnitude of the varying resistance of the magnetoresistive structure corresponds to a zero current of the current signal to be sensed.

2. The detection system according to claim 1, wherein the detection unit is configured to detect a magnitude of the varying resistance of the magnetoresistive structure by generating a sensor signal indicating the resistance of the magnetoresistive structure and compare the sensor signal with a predefined threshold indicating a resistance of the magnetoresistive structure at the zero current of the current signal to be sensed.

3. The detection system according to claim 1, wherein the magnetoresistive structure comprises at least a non-magnetic layer arranged between a first magnetic layer and a second magnetic layer, so that the resistance of this layer stack varies depending on a magnetic field caused by a current of the signal to be sensed.

4. The detection system according to claim 3, wherein the non-magnetic layer is an electrically conductive layer, so that the variation of the resistance is based on a giant magnetoresistive effect, or the non-magnetic layer is an electrically insulating layer, so that the variation of the resistance is based on a tunnel magnetoresistive effect.

5. The detection system according to claim 1, wherein the detection unit is configured to generate the zero current detection signal indicating a temporal occurrence of the zero current of the current signal to be sensed, wherein the zero current of the current signal to be sensed comprises the zero current with a frequency of more than 1 kHz.

6. The detection system according to claim 1, wherein the magnetoresistive structure and an electrically conductive line configured to carry the signal to be sensed are manufactured on the same semiconductor die.

7. The detection system according to claim 6, wherein the magnetoresistive structure is manufactured between an intermetallic oxide layer and a passivation layer of the semiconductor die, wherein a part of the electrically conductive line closest to the magnetoresistive structure is manufactured directly below the magnetoresistive structure with the intermetallic oxide layer in between.

8. The detection system according to claim 1, comprising a switching element, wherein the detection unit is configured to provide the current detection signal to the switching element, so that a switching of the switching element is triggered by an occurrence of the zero current of the current signal to be sensed.

9. The detection system according to claim 1, wherein the magnetoresistive structure is at least partly surrounded by inductor coil carrying the current signal to be sensed.

10. The detection system according to claim 9, wherein the detection unit is configured to generate a status signal indicating a status of the coil.

11. The detection system according to claim 1, wherein the detection unit is configured to generate a measurement signal indicating information on a magnetic field strength or a current strength of the current signal to be sensed.

12. The detection system according to claim 1, wherein the detector further comprises an adjuster configured to adjust the adjustment signal based on the sensitivity of the magnetoresistive structure to a range of maximal sensitivity of the magnetoresistive structure so that a magnetic field caused by the zero current of the current signal to be sensed lies in the range of maximal sensitivity of the magnetoresistive structure.

13. A method for detecting an occurrence of a zero current of the current signal to be sensed comprising:

generating a current detection signal indicating the zero current of the current signal to be sensed using a magnetoresistive structure configured to vary a resistance depending on a magnetic field caused by a current of the current signal to be sensed, the generation of the current detection signal being based on a detected magnitude of the varying resistance of the magnetoresistive structure and an adjustment signal; and

adjusting the adjustment signal based on the current detection signal and a sensitivity of the magnetoresistive structure.

14. The method according to claim 13, the method comprising:

providing the current detection signal.

15. A detection system for detecting an occurrence of a zero current of a current signal to be sensed, the detection system comprising:

a magnetoresistive structure configured to vary a resistance depending on a magnetic field caused by the current signal to be sensed; and

a detector configured to;

generate and provide a current detection signal indicating zero current of the current signal based on a detected magnitude of the varying resistance of the magnetoresistive structure and an adjustment signal; and

generate the adjustment signal based on the current detection signal and a sensitivity of the magnetoresistive structure, wherein the magnetoresistive structure and an electrically conductive line configured to carry the current signal to be sensed are manufactured on the same semiconductor die.