Medical cable including authentication circuit

• US 9,300,356 B2
• Filed: 10/14/2014
• Issued: 03/29/2016
• Est. Priority Date: 04/16/2012
• Status: Active Grant

• Current Assignee: ICU Medical Incorporated
• Original Assignee: ICU Medical Incorporated
• Inventors: Winward, Kelsey Brendon, Wong, Kwok-Kwong, MacDonald, Douglas B.
• Primary Examiner(s): Kim, Kevin
• Application Number:
  US14/514,299
• Publication Number:
  US 20150155912A1
• Time in Patent Office: 532 Days
• Field of Search: 375/224, 375/227, 375/228
• US Class Current: 1/1
• CPC Class Codes: A61B 2017/00482 with a code
• CPC Class Codes: A61B 2562/222 Electrical cables or leads therefor, e.g. coaxial cables or ribbon cables
• CPC Class Codes: A61B 2562/226 comprising means for identifying the connector, e.g. to prevent incorrect connection to socket
• CPC Class Codes: A61B 2562/227 Sensors with electrical connectors
• CPC Class Codes: A61B 5/015 By temperature mapping of body part
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/7225 Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation A61B5/30, A61B5/316 take precedence; transformers for specific applications H01F38/00; amplifiers H03F
• CPC Class Codes: G01R 31/68 Testing of releasable connections, e.g. of terminals mounted on a printed circuit board
• CPC Class Codes: G16H 40/40 for the management of medical equipment or devices, e.g. scheduling maintenance or upgrades
• CPC Class Codes: H04B 3/02 Details

Abstract

Medical cable authentication apparatuses and methods are disclosed. Some embodiments herein provide a medical cable assembly for use in a patient monitoring system including authentication circuit. The authentication circuit can provide a signal indicative of whether the medical cable assembly is compatible, or desirable for use with a particular patient monitor and/or sensor. The authentication circuit can include a substantially constant current source that drives a capacitor, wherein a voltage signal provided by a patient monitor drives the current source, and the voltage across the capacitor is used to generate an authentication output signal.

Claims

1. A medical cable for transmitting data between a patient monitor and a sensor, the medical cable comprising:

a cable body;

a first connector connected to the cable body and configured to be coupled to a patient monitor;

a second connector connected to the cable body, the second connector configured to be coupled to a sensor and to receive a sensor signal from the sensor that comprises information related to the one or more physiological parameters; and

an authentication circuit, configured to receive a test signal from the patient monitor and generate an output ramp signal responsive to the test signal that reaches a target voltage within an amount of time expected by the patient monitor, thereby enabling the monitor to authenticate the medical cable,

wherein the second connector comprises a portion of an electrically conductive path in series with a switch, the conductive path configured to transmit the test signal from the patient monitor to the authentication circuit, said second connector configured to close the switch in response to being coupled to the sensor.

2. The medical cable of claim 1, wherein the authentication circuit is further configured to provide the output ramp signal to the patient monitor.

3. The medical cable of claim 1, wherein the authentication circuit further comprises a diode, wherein the authentication circuit is configured such that activation of the diode allows for the capacitor to at least partially discharge through the diode.

4. The medical cable of claim 1, wherein the test signal is a square wave having a predetermined pulse width.

5. The medical cable of claim 1, wherein the authentication circuit is disposed within the first connector.

6. The medical cable of claim 1, wherein the second connector comprises a housing, the authentication circuit being contained within the housing.

7. The medical cable of claim 1, wherein the second connector comprises a plurality of circuit boards disposed in a parallel configuration, the plurality of circuit boards being perpendicular to a longitudinal axis of the medical cable.

8. The medical cable of claim 1, wherein the transmission of data between the patient monitor and the sensor through the medical cable is partially prohibited when the authentication circuit fails to provide the output signal to the patient monitor at a set time after the sensor and the medical cable are physically connected.

9. The medical cable of claim 1, wherein the target voltage is between about 2 volts to about 4 volts.

10. The medical cable of claim 1, wherein the target time period is between about 100 μ

S and about 170 μ

S.

18. The medical cable of claim 1, wherein the authentication circuit comprises a substantially constant current source coupled to a capacitor configured to generate the output ramp signal.

11. A method of transmitting data between a patient monitor and a sensor, the method comprising:

connecting a medical cable to a patient monitor;

receiving a test signal with an authentication circuit disposed in the medical cable;

converting the test signal into a substantially constant current signal;

generating a ramp signal using the current signal; and

providing the ramp signal to the patient monitor, thereby enabling the monitor to authenticate the medical cable,

wherein the transmission of data between the patient monitor and the sensor through the medical cable is partially prohibited when the authentication circuit fails to provide the output signal to the patient monitor at a set time after the sensor and the medical cable are physically connected.

12. The method of claim 11, further comprising:

receiving a confirmation signal from the patient monitor indicating that the medical cable is in an authenticated state.

13. The method of claim 11, further comprising:

using the medical cable, transmitting a sensor signal that comprises information related to one or more physiological parameters from a sensor to the patient monitor.

14. A medical cable for transmitting data between a patient monitor and a sensor, the medical cable comprising:

a cable body;

a first connector connected to the cable body and configured to be coupled to a patient monitor;

a second connector connected to the cable body, the second connector configured to be coupled to a sensor and to receive a sensor signal from the sensor; and

a safety switch configured to be triggered by a connection between the second connector and the sensor, the safety switch configured to be in a first state when the second connector is coupled to the sensor and in a second state when the second connector is not coupled to the sensor.

15. The medical cable of claim 14, wherein the safety switch at least partially prevents the patient monitor from outputting a measurement value when the sensor is not connected to the second connector.

16. The medical cable of claim 14, wherein the first state is an electrically closed state and the second state is an electrically open state.

17. The medical cable of claim 14, wherein the safety switch prevents an authentication circuit disposed in the cable from receiving power from the patient monitor, thereby preventing the authentication circuit from authenticating to the patient monitor.

19. The medical cable of claim 14, wherein the safety switch prevents authentication of the cable to the patient monitor when the safety switch is in the second state.

20. A medical cable for transmitting data between a patient monitor and a sensor, the medical cable comprising:

a cable body;

a first connector connected to the cable body and configured to be coupled to a patient monitor;

a second connector connected to the cable body, the second connector configured to be coupled to a sensor and to receive a sensor signal from the sensor that comprises information related to the one or more physiological parameters; and

an authentication circuit, configured to receive a test signal from the patient monitor and generate an output ramp signal responsive to the test signal that reaches a target voltage within an amount of time expected by the patient monitor, thereby enabling the monitor to authenticate the medical cable,

wherein the transmission of data between the patient monitor and the sensor through the medical cable is partially prohibited when the authentication circuit fails to provide the output signal to the patient monitor at a set time after the sensor and the medical cable are physically connected.

21. The medical cable of claim 20, wherein the test signal is a square wave having a predetermined pulse width.

22. The medical cable of claim 20, wherein the authentication circuit is further configured to provide the output ramp signal to the patient monitor.

23. The medical cable of claim 20, wherein the target voltage is between about 2 volts to about 4 volts.

24. The medical cable of claim 20, wherein the target time period is between about 100 μ

S and about 170 μ

S.

25. A medical cable for transmitting data between a patient monitor and a sensor, the medical cable comprising:

a cable body;

a first connector connected to the cable body and configured to be coupled to a patient monitor;

a second connector connected to the cable body, the second connector configured to be coupled to a sensor and to receive a sensor signal from the sensor that comprises information related to the one or more physiological parameters; and

an authentication circuit, configured to receive a test signal from the patient monitor and generate an output ramp signal responsive to the test signal that reaches a target voltage within an amount of time expected by the patient monitor, thereby enabling the monitor to authenticate the medical cable,

wherein the authentication circuit further comprises a diode and wherein the authentication circuit is configured such that activation of the diode allows for the capacitor to at least partially discharge through the diode.

26. The medical cable of claim 25, wherein the test signal is a square wave having a predetermined pulse width.

27. The medical cable of claim 25, wherein the authentication circuit is further configured to provide the output ramp signal to the patient monitor.

28. The medical cable of claim 25, wherein the target voltage is between about 2 volts to about 4 volts.

29. The medical cable of claim 25, wherein the target time period is between about 100 μ

S and about 170 μ

S.

30. A medical cable for transmitting data between a patient monitor and a sensor, the medical cable comprising:

a cable body;

a first connector connected to the cable body and configured to be coupled to a patient monitor;

a second connector connected to the cable body, the second connector configured to be coupled to a sensor and to receive a sensor signal from the sensor that comprises information related to the one or more physiological parameters; and

an authentication circuit, configured to receive a test signal from the patient monitor and generate an output ramp signal responsive to the test signal that reaches a target voltage within an amount of time expected by the patient monitor, thereby enabling the monitor to authenticate the medical cable,

wherein the second connector comprises a plurality of circuit boards disposed in a parallel configuration, the plurality of circuit boards being perpendicular to a longitudinal axis of the medical cable.

31. The medical cable of claim 30, wherein the test signal is a square wave having a predetermined pulse width.

32. The medical cable of claim 30, wherein the authentication circuit is further configured to provide the output ramp signal to the patient monitor.

33. The medical cable of claim 30, wherein the target voltage is between about 2 volts to about 4 volts.

34. The medical cable of claim 30, wherein the target time period is between about 100 μ

S and about 170 μ

S.