Connector with active shielding

• US 9,977,096 B2
• Filed: 07/07/2011
• Issued: 05/22/2018
• Est. Priority Date: 07/07/2011
• Status: Active Grant

• Current Assignee: Biosense Webster Israel Ltd. (Johnson & Johnson)
• Original Assignee: Biosense Webster Israel Ltd. (Johnson & Johnson)
• Inventors: Govari, Assaf, Altmann, Andres Claudio, Ephrath, Yaron
• Primary Examiner(s): Smith, Ruth S
• Application Number:
  US13/178,054
• Publication Number:
  US 20130012808A1
• Time in Patent Office: 2,511 Days
• Field of Search: 600466, 439 39, 439 88
• CPC Class Codes: A61B 5/062 using magnetic field
• CPC Class Codes: G01R 33/025 Compensating stray fields G01R33/0017 takes precedence

Abstract

An electrical connector includes one or more connector terminals, which are connected to wiring extending from the connector and are coupled to interconnect with corresponding connector terminals in a mating connector. An active shielding circuit is mounted adjacent to the connector terminals and is configured to sense a first magnetic field in a vicinity of the electrical connector and to generate, based on the sensed magnetic field, a second magnetic field that reduces interference induced in the wiring and the connector terminals by the first magnetic field.

Claims

1. An electrical connector, comprising:

a connector housing;

one or more connector terminals fitted within the connector housing, which are connected to wiring extending from the connector housing and are coupled to interconnect with corresponding connector terminals in a mating connector; and

an active shielding circuit, mounted adjacent to the one or more connector terminals within the connector housing and is configured to sense a first magnetic field in a vicinity of the electrical connector and to generate, based on the sensed magnetic field, a second magnetic field that reduces interference induced in the wiring and the one or more connector terminals by the first magnetic field, the active shielding circuit comprising;

at least one sense coil for sensing the first magnetic field;

at least one generator coil for generating the second magnetic field; and

a drive circuit comprising;

an operational amplifier receiving a first input from a terminal of the at least one sense coil and a second input from a terminal of the at least one generator coil, the operational amplifier capable of amplifying a difference between the first input and the second input;

an integrator receiving an amplified signal from the operational amplifier, the integrator capable of integrating the amplified signal;

a low-pass filter receiving the integrated signal from the integrator, the low-pass filter capable of filtering the integrated signal;

a voltage-to-current (V/I) converter receiving the filtered signal from the low-pass filter, the V/I converter capable of converting a voltage of the filtered signal to a current signal; and

a current source receiving the current signal from V/I converter, the current source driving the at least one generator coil.

2. The electrical connector according to claim 1, wherein the one or more connector terminals are arranged in a plane, and wherein the at least one sense coil and the at least one generator coil are parallel to the plane.

3. The electrical connector according to claim 2, wherein the at least one generator coil comprises first and second generator coils located respectively on first and second opposing sides of the plane containing the one or more connector terminals.

4. The electrical connector according to claim 1, wherein the at least one sense coil and the at least one generator coil are disposed on at least one Printed Circuit Board (PCB).

5. The electrical connector according to claim 1, wherein the active shielding circuit is matched to a frequency range of the first magnetic field.

6. The electrical connector according to claim 1, wherein the second magnetic field is equal in amplitude and opposite in polarity to the first magnetic field.

7. The electrical connector according to claim 1, wherein the drive circuit is matched to a frequency range of an external magnetic field.

8. The electrical connector according to claim 1, wherein a coil circuit comprising the at least one sense coil and the at least one generator coil is matched to a frequency range of an external magnetic field.

9. A catheter, comprising:

an elongated hollow shaft having a proximal end and a distal end;

a transducer fitted in the distal end of the hollow shaft;

a cable for exchanging electrical signals with the transducer; and

an electrical connector connected to the cable for transferring the electrical signals, the electrical connector comprising;

a connector housing,

one or more connector terminals fitted within the connector housing, which are connected to wiring extending from the connector housing and are coupled to interconnect with corresponding one or more connector terminals in a mating connector, and

an active shielding circuit mounted adjacent to the one or more connector terminals within the connector housing and is configured to sense a first magnetic field in a vicinity of the electrical connector and to generate, based on the sensed magnetic field, a second magnetic field that reduces interference induced in the wiring and the one or more connector terminals by the first magnetic field, the active shielding circuit comprising;

at least one sense coil for sensing the first magnetic field;

at least one generator coil for generating the second magnetic field; and

a drive circuit comprising;

an operational amplifier receiving a first input from a terminal of the at least one sense coil and a second input from a terminal of the at least one generator coil, the operational amplifier capable of amplifying a difference between the first input and the second input;

an integrator receiving an amplified signal from the operational amplifier, the integrator capable of integrating the amplified signal;

a low-pass filter receiving the integrated signal from the integrator, the low-pass filter capable of filtering the integrated signal;

a voltage-to-current (V/I) converter receiving the filtered signal from the low-pass filter, the V/I converter capable of converting a voltage of the filtered signal to a current signal; and

a current source receiving the current signal from V/I converter, the current source capable of driving the at least one generator coil.

10. A method, comprising:

transferring one or more signals via an electrical connector having a connector housing comprising one or more connector terminals fitted within the connector housing that are connected to wiring extending from the connector housing and are coupled to interconnect with corresponding one or more connector terminals in a mating connector;

sensing within the connector housing a first magnetic field in a vicinity of the electrical connector, sensing the first magnetic field comprising measuring the first magnetic field using at least one sense coil;

producing an amplified signal by amplifying a difference between a current in the at least one sense coil and a current in at least one generator coil;

producing an integrated signal by integrating the amplified signal;

producing a filtered signal by filtering the integrated signal;

converting a voltage of the filtered signal to a current signal to drive a current source that injects current into the at least one generator coil; and

generating with the at least one generator coil a second magnetic field that reduces interference induced in the signals at the wiring and the one or more connector terminals by the first magnetic field, the second magnetic field based on the sensed magnetic field.

11. The method according to claim 10, wherein the one or more connector terminals are arranged in a plane, and wherein the at least one sense coil and the at least one generator coil are parallel to the plane.

12. The method according to claim 11, wherein generating the second magnetic field comprises producing the second magnetic field using first and second generator coils located respectively on first and second opposing sides of the plane containing the one or more connector terminals.

13. The method according to claim 10, wherein the at least one sense coil and the at least one generator coil are disposed on at least one Printed Circuit Board (PCB).

14. The method according to claim 10, wherein sensing the first magnetic field and generating the second magnetic field comprise operating circuitry matched to a frequency range of the first magnetic field.

15. The method according to claim 10, wherein the second magnetic field is equal in amplitude and opposite in polarity to the first magnetic field.

16. The method according to claim 10, wherein the production of the amplified signal, production of the integrated signal, production of the filtered signal, and conversion of the voltage of the filtered to the current signal are performed within a circuit matching a frequency range of an external magnetic field.

17. The method according to claim 10, further comprising matching a frequency of a coil circuit comprising the at least one sense coil and the at least one generator coil to a frequency range of an external magnetic field.