Isolating system that couples fieldbus data to a network

• US 20060155908A1
• Filed: 01/12/2005
• Published: 07/13/2006
• Est. Priority Date: 01/12/2005
• Status: Active Grant

• Current Assignee: Rosemount Incorporated (Emerson Electric Company)
• Original Assignee: Rosemount Incorporated (Emerson Electric Company)
• Inventors: Holmstadt, Clarence Edward, Rotvold, Eric Darrell, Brewer, John P.
• Granted Patent: US 7,421,531 B2
• Time in Patent Office: Days
• US Class Current: 710/315
• CPC Class Codes: H04L 12/10 Current supply arrangements
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 25/0266 Arrangements for providing Galvanic isolation, e.g. by means of magnetic or capacitive coupling

Abstract

A system couples fieldbus data from a fieldbus line to a network line. The system includes a data format converter that converts the data to USB data. A coupler that includes a first insulating barrier is coupled in cascade with the converter. A host receives the USB data. The host has a data server interface and a network connection. The data server interface presents the data to the network line. A regulator couples power between the host and the fieldbus line with the regulator including a second insulating barrier. Data and power are isolatingly coupled between the fieldbus line and the network line.

Claims

1. A system for coupling data received in fieldbus format from a fieldbus interface to a network connection, comprising:

a data format converter coupled between the fieldbus interface and a bridge USB interface, the converter converting the data to USB-formatted data;

a coupler coupled in cascade with the converter, and including a first insulating barrier;

a host that receives the USB-formatted data, and that includes a data server interface presenting the data to the network connection; and

regulator coupling power between the bridge USB interface and the fieldbus interface, the regulator including a second insulating barrier such that data and power are isolatingly coupled between the fieldbus interface and the bridge USB interface.

2. The system of claim 1 wherein the coupler comprises a bidirectional magnetoresistive coupler.

3. The system of claim 1 wherein the coupler comprises a bidirectional optical coupler.

4. The system of claim 1 wherein the host comprises a fieldbus data table coupled to the data server interface.

5. The system of claim 1 wherein the data format converter, coupler and regulator are included in a bridge.

6. The system of claim 5 wherein the bridge USB interface couples to the data format converter and the regulator, the host comprises a host USB interface, and the system further comprises a USB cable coupled between the bridge and host USB interfaces.

7. The system of claim 6 wherein the regulator comprises a power limiter that sets a power limit for power flow between the bridge USB interface to the fieldbus interface.

8. The system of claim 7 wherein the regulator comprises a shutoff circuit that senses power availability at the fieldbus interface and automatically reduces power drawn from the bridge USB interface when a fieldbus line applies power to the fieldbus interface.

9. The system of claim 8 wherein the regulator comprises a diode “

OR”

circuit drawing power from either the bridge USB interface or the fieldbus line, the diode “

OR”

circuit blocking power flow from the fieldbus line back into the regulator when power is supplied by the fieldbus line.

10. The system of claim 8 wherein the shutoff circuit couples to the power limiter to the shut off power taken from the bridge USB interface when power is provided at the fieldbus line.

11. The system of claim 1 wherein the regulator includes an isolated DC-to-DC converter that includes the second insulating barrier.

12. The system of claim 11 wherein the converter provides a suspend output that is coupled to the isolated DC-to-DC converter for suspending operation of the DC-to-DC converter when the first USB interface is idle.

13. The system of claim 1 wherein the converter automatically senses protocol characteristics at the fieldbus interface and adjusts its operation to the sensed protocol characteristics.

14. The system of claim 1 wherein the regulator comprises a DC/DC converter that couples power from the bridge USB interface to the fieldbus interface.

15. The system of claim 1 wherein the regulator comprises a DC/DC converter that couples power from the fieldbus interface to the converter.

16. A method for coupling fieldbus data from a fieldbus line to a network line, comprising:

converting the fieldbus data to USB data;

coupling a first insulating barrier in cascade with the converting;

receiving the USB data at a host,

providing the host with a data server interface and a network connection, the data server interface presenting the USB data to the network connection; and

coupling power between the host and the fieldbus line through a second insulating barrier such that data and power are isolatingly coupled between the fieldbus interface and the network connection.

17. The method of claim 16, and:

providing a bidirectional magnetoresistive coupler that includes the first insulating barrier.

18. The method of claim 16, and:

providing a bidirectional optical coupler that includes the first insulating barrier.

19. The method of claim 16, and:

coupling data in the host from a fieldbus data table to a data server interface.

20. The method of claim 16, and providing a bridge to perform the converting, the coupling of the first insulation barrier and coupling of power.

21. The method of claim 20, and

coupling data between a bridge USB interface in the bridge to a host USB interface in the host via a USB cable.

22. The method of claim 21, and:

setting a power limit for power flow from the bridge USB interface to the fieldbus interface.

23. The method of claim 21, and:

sensing power availability at the fieldbus interface and automatically reducing power drawn from the bridge USB interface when power is supplied by a fieldbus line.

24. The method of claim 23, and

providing power to the fieldbus line through a diode “

OR”

circuit from either the first USB interface or the fieldbus line, the diode “

OR”

circuit blocking power flow from the fieldbus line back into the regulator when power is supplied by the fieldbus line.

25. The method of claim 23, and:

shutting off power taken from the first USB interface when power is provided at the external fieldbus power input.

26. The method of claim 16, and:

providing an isolated DC-to-DC converter that includes the second insulating barrier in the regulator.

27. The method of claim 26, and:

providing a suspend output to the isolated DC-to-DC converter for suspending operation of the DC-to-DC converter when the first USB interface is idle.

28. The method of claim 16, and

automatically sensing protocol characteristics on the fieldbus line and adjusts operation to the sensed protocol characteristics.

29. The method of claim 16 wherein the coupling of power includes DC/DC converting that couples power from the bridge USB interface to the fieldbus interface.

30. The method of claim 16 wherein the coupling of power includes DC/DC conversion that couples power from the fieldbus interface to the converter.

31. A system for coupling data received in fieldbus format from a fieldbus interface to a host, comprising:

a data format converter coupled between the fieldbus interface and a bridge USB interface, the converter converting the data to USB-formatted data that is couplable to the host;

a coupler coupled in cascade with the converter, and including a first insulating barrier; and

a regulator coupling power between the bridge USB interface and the fieldbus interface, the regulator including a second insulating barrier such that data and power are isolatingly coupled between the fieldbus interface and the bridge USB interface.