Voltage isolation buffer with AC coupled and DC coupled hall effect magnetic field sensors

• US 7,042,208 B1
• Filed: 03/07/2005
• Issued: 05/09/2006
• Est. Priority Date: 02/15/2002
• Status: Expired due to Term

• Current Assignee: OL Security LLC (Intellectual Ventures LLC)
• Original Assignee: Larry L. Harris
• Inventors: Harris, Larry L.
• Primary Examiner(s): Nguyen, Vinh P.
• Application Number:
  US11/074,353
• Time in Patent Office: 428 Days
• Field of Search: 324/158.1, 324117 R-117 H, 324126-127, 324250-252
• US Class Current: 324/117.00H
• CPC Class Codes: G01D 18/006 Intermittent recalibration
• CPC Class Codes: G01D 21/00 Measuring or testing not otherwise provided for
• CPC Class Codes: G01D 3/08 with provision for safeguarding the apparatus, e.g. against abnormal operation, against breakdown

Abstract

A voltage isolation buffer, including a pilot channel having a first Hall effect element and a data channel having a second Hall effect element is disclosed. The pilot channel is preferably AC coupled, and the data channel is preferably DC coupled. The voltage isolation buffer may include a calibration engine, which may be configurable to calibrate the voltage generated by the second Hall effect element based on the information from the first Hall effect element. A bi-directional voltage isolation buffer is also disclosed, including a first integrated circuit and a second integrated circuit. The first integrated circuit includes a DC coupled Hall effect sensor and an AC coupled Hall effect sensor. The second integrated circuit includes an AC coupled Hall effect sensor and a DC coupled Hall effect sensor. A method for transmitting data across a voltage isolation barrier is also disclosed including the steps of generating a first hall voltage signal, AC coupling the first Hall voltage signal, generating a second Hall voltage signal, DC coupling the second Hall voltage signal, and calibrating the second Hall voltage signal, wherein the step of calibrating is controlled by the first Hall voltage signal.

Claims

1. A voltage isolation buffer comprising:

an AC coupled Hall effect sensor;

a plurality of DC coupled Hall effect sensors; and

a means for calibration;

wherein the AC coupled Hall effect sensor is operatively coupled to the means for calibration; and

wherein each of the plurality of DC coupled Hall effect sensors is operatively coupled to the means for calibration.

2. A system for transmitting data across a voltage isolation barrier via a magnetic field, the system comprising:

a first pilot channel comprising an AC coupled Hall effect sensor; and

a plurality of data channels, wherein each of the plurality of data channels comprises a DC coupled Hall effect sensor, and wherein each of the plurality of data channels further comprises a means for calibration operatively coupled to the AC coupled Hall effect sensor;

wherein the means for calibration is operatively coupled to each DC coupled Hall effect sensor;

wherein the means for calibration is configurable to receive information from the AC coupled Hall effect sensor; and

wherein the means for calibration is configurable to calibrate each DC coupled Hall effect sensor based on the information from the AC coupled Hall effect sensor.

3. A bi-directional voltage isolation buffer comprising:

a first integrated circuit; and

a second integrated circuit adjacent to the first integrated circuit;

wherein the first integrated circuit comprises a first AC coupled Hall effect sensor operable to receive a pilot signal from the second integrated circuit;

wherein the first integrated circuit comprises a first DC coupled Hall effect sensor operable to receive a control signal from the first AC coupled Hall effect sensor;

wherein the second integrated circuit comprises a second AC coupled Hall effect sensor operable to receive a pilot signal from the first integrated circuit; and

wherein the second integrated circuit comprises a second DC coupled Hall effect sensor operable to receive a control signal from the second AC coupled Hall effect sensor.

4. The bi-directional voltage isolation buffer of claim 3, wherein the first integrated circuit comprises a means for calibration operatively coupled to the first AC coupled Hall effect sensor.

5. The bi-directional voltage isolation buffer of claim 4, wherein the means for calibration is configurable to calibrate the first DC coupled Hall effect sensor based on information from the first AC coupled Hall effect sensor.

6. The bi-directional voltage isolation buffer of claim 3, wherein the second integrated circuit comprises a means for calibration operatively coupled to the second AC coupled Hall effect sensor.

7. The bi-directional voltage isolation buffer of claim 6, wherein the means for calibration is configurable to calibrate the second DC coupled Hall effect sensor based on information from the second AC coupled Hall effect sensor.

8. The bi-directional voltage isolation buffer of claim 3, wherein the first integrated circuit comprises a third DC coupled Hall effect sensor operable to receive a control signal from the first AC coupled Hall effect sensor.

9. The bi-directional voltage isolation buffer of claim 3, wherein the second integrated circuit comprises a third DC coupled Hall effect sensor operable to receive a control signal from the second AC coupled Hall effect sensor.

10. The bi-directional voltage isolation buffer of claim 3, wherein the first DC coupled Hall effect sensor is operable to receive a data signal from the second integrated circuit.

11. The bi-directional voltage isolation buffer of claim 3, wherein the first DC coupled Hall effect sensor is operable to receive a data signal from the first integrated circuit.