Switching module

Patent metadata

Field	Value
Publication number	US-10103622-B2
Application number	US-201414458925-A
Country	US
Kind code	B2
Filing date	Aug 13, 2014
Priority date	Feb 13, 2014
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

A switching module comprising at least one power switching device arranged to output from an output node thereof a load current for the switching module, and at least one current sense component arranged to generate at least one sense current representative of the load current. The at least one current sense component comprises at least one temperature coefficient compensation resistance within the path of the at least one sense current and arranged to cause the at least one sense current to be at least partly compensated for a temperature coefficient caused by at least one parasitic routing resistance of a load current path for the at least one power switching device.

First claim

The invention claimed is:

1. A switching module comprising:
a power switching device arranged to output from an output node thereof a load current for the switching module; and
a current sense component arranged to generate a sense current representative of the load current, the a current sense component comprising:
a temperature coefficient compensation resistance within a path of the sense current and arranged to cause the sense current to be at least partly compensated for a temperature coefficient caused by a parasitic routing resistance of a load current path for the power switching device, wherein the temperature coefficient compensation resistance is based on a plurality of resistors that combine to comprise a plurality of tap points via which a differential amplifier may be selectively coupled to a source node of the current sense device.

2. The switching module of claim 1 , wherein the temperature coefficient compensation resistance is arranged to comprise a resistance, Rmet_cmp, equal to a target load:sense ratio, RATIO, times higher than the parasitic routing resistance, Rmet_main, for the load current path of the power switching device, such that:
R met_cmp= R met_main*RATIO.

3. The switching module of claim 2 , wherein the parasitic routing resistance comprises a metal resistor element within the path of the sense current.

4. The switching module of claim 1 , wherein the temperature coefficient compensation resistance is arranged to comprise a resistance, Rmet_cmp, equal to a target load:sense ratio, RATIO, times higher than the parasitic routing resistance, Rmet_main, for the load current path of the power switching device, less a parasitic routing resistance, Rmet_sense, for the path of the sense current, such that:
R met_cmp=( R met_main*RATIO)− R met_sense.

5. The switching module of claim 4 , wherein the parasitic routing resistance comprises a metal resistor element within the path of the sense current.

6. The switching module of claim 1 , wherein the parasitic routing resistance comprises a metal resistor element within the path of the sense current.

7. The switching module of claim 1 , wherein the current sense component comprises a current sense device arranged such that a current flow through the current sense device is proportional to the load current through the power switching device, the current flow through the current sense device comprising the sense current.

8. The switching module of claim 7 , wherein the power switching device and the current sense device each comprises a field effect transistor, FET, device.

9. The switching module of claim 1 , wherein the switching module is arranged to output a current sense signal based at least partly on the sense current.

10. The switching module of claim 9 , wherein the switching module comprises a digital to analogue converter arranged to output a digital code for the value of the load current based at least partly on the sense current.

11. The switching module of claim 9 , wherein the switching module is arranged to generate a current sense signal comprising a current representative of the load current, the current sense signal being generated based at least partly on the sense current.

12. The switching module of claim 1 implemented within an integrated circuit device comprising a die within a single integrated circuit package.

13. A method comprising:
outputting, from an output node of a power switching device of a switching module, a load current for the switching module, and
generating, by a current sense component, a sense current representative of the load current; the current sense component comprising:
partly compensating, by a temperature coefficient compensation resistance within a path of a sense current, the sense current for a temperature coefficient caused by a parasitic routing resistance of a load current path for the power switching device, wherein the temperature coefficient compensation resistance is based on a plurality of resistors that combine to comprise a plurality of tap points via which a differential amplifier may be selectively coupled to a source node of a current sense device of the current sense component.

14. The method of claim 13 , wherein the parasitic routing resistance comprises a metal resistor element within the path of the sense current.

15. The method of claim 13 , further comprising:
providing, by a current sense device of the current sense component, a current flow through the current sense device that is proportional to the load current through the power switching device, wherein the current flow through the current sense device includes the sense current.

16. The method of claim 15 , wherein the power switching device and the current sense device each comprises a field effect transistor, FET, device.

17. The method of claim 13 , further comprising:
outputting, by the switching module, a current sense signal based at least partly on the sense current.

18. A switching module comprising:
a power switching device arranged to output from an output node thereof a load current for the switching module;
a differential amplifier comprising:
differential inputs arranged to be operably coupled to a source node of the power switching device, and an output arranged to output a signal representative of the sense current flowing through the current sense device; and

a current sense component arranged to generate a sense current representative of the load current, the current sense component comprising:
a current sense device including a source node operably coupled to the differential inputs of the differential amplifier; and
a temperature coefficient compensation resistance within the path of the sense current and arranged to cause the sense current to be at least partly compensated for a temperature coefficient caused by a parasitic routing resistance of a load current path for the power switching device, wherein the temperature coefficient compensation resistance is based on a plurality of resistors that combine to comprise a plurality of tap points via which a differential amplifier may be selectively coupled to a source node of a current sense device of the current sense component.

Assignees

• Syngaevskiy Vasily Alekseyevich
• Nxp Usa Inc

Inventors

• Syngaevskiy Vasily Alekseyevich

Classifications

• H02M3/158

  including plural semiconductor devices as final control devices for a single load · CPC title

• H02M3/155 Primary

  using semiconductor devices only · CPC title

• H02M2001/0009

  Electricity · mapped topic

• H02M1/0009

  Devices or circuits for detecting current in a converter · CPC title