Over-current protection device

Patent metadata

Field	Value
Publication number	US-9787079-B2
Application number	US-201214372608-A
Country	US
Kind code	B2
Filing date	Jan 20, 2012
Priority date	Jan 20, 2012
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

An over-current protection circuit including, a current supply switch with a first terminal coupled to a supply current input and with a second terminal coupled to a supply current output. The current supply switch is switchable at least between an on-state, in which the current supply switch provides a conductive connection between the first terminal and the second terminal, and an off-state, in which the current supply switch interrupts the conductive connection between the first terminal and the second terminal. The over-current protection circuit receives a supply current via the supply current input and provides the supply current via the supply current output if the switch is in the on-state. The current supply switch includes a High Electron Mobility Transistor.

First claim

The invention claimed is:

1. An over-current protection circuit comprising:
a supply current input;
a supply current output;
a current supply switch comprising
a first switch terminal coupled to the supply current input,
a second switch terminal coupled to the supply current output,
a third switch terminal coupled to a gate driver, and
a high electron mobility transistor (HEMT) comprising a first current electrode coupled to the first switch terminal, a second current electrode coupled to the second switch terminal, and a control electrode coupled to the third switch terminal, wherein
the current supply switch provides an on-state, in which the current supply switch provides a conductive connection between the first switch terminal and the second switch terminal, and an off-state, in which the current supply switch interrupts the conductive connection between the first switch terminal and the second switch terminal wherein the HEMT is a normally-on transistor;

a sense transistor comprising a first current electrode coupled to the first switch terminal, a second current electrode, and a control electrode coupled to the third switch terminal; and
a switch control device including:
an operational amplifier having a first input terminal coupled to the second current electrode of the sense transistor, a second input terminal coupled to the second switch terminal, and an output terminal:
a comparator transistor having a first current electrode coupled to the in put terminal of the operational amplifier, a second current electrode, and a control electrode coupled to the output terminal of the operational amplifier; and
a comparator having an input terminal coupled to the second current electrode of the comparator transistor, and an output terminal coupled to the gate driver;
the switch control device arranged to control the current supply switch of an over-current protection device based on level of a supply current provided to the over-current protection circuit, and to control the current supply switch into the off-state if the supply current is larger than a limit current, and wherein the over-current protection circuit provides an instant reaction to the supply current being larger than the limit current based on the HEMT being the normally-on transistor; and

the over-current protection circuit is configured to receive the supply current via the supply current input and to provide the supply current via the supply current output if the current supply switch is in the on-state.

2. Over-current protection circuit according to claim 1 , wherein the HEMT is a bidirectional transistor.

3. Over-current protection circuit according to claim 1 , wherein the HEMT is a GaN transistor.

4. Over-current protection circuit according to claim 1 , further comprising a current measure device arranged for measurement of the supply current.

5. Over-current protection circuit according to claim 4 , wherein the current supply switch is connected or connectable to the switch control device arranged to control the current supply switch to switch between the on-state and the off-state or vice versa.

6. Over-current protection circuit according to claim 5 , wherein the switch control device is arranged to control the current supply switch based on a current value measured via the current measure device.

7. Over-current protection circuit according to claims 4 , wherein the current measure device comprises a measurement HEMT.

8. Over-current protection circuit according to claim 7 , wherein the measurement HEMT is arranged on the same die as the HEMT of the current supply switch.

9. Over-current protection device according to claim 1 , wherein the switch control device comprises a limit current control device arranged to set at least one limit current.

10. Over-current protection device according to claim 9 , wherein the at least one limit current represents an upper limit for supply current.

11. Over-current protection device according to claim 1 , wherein the switch control device is arranged to compare the supply current to the limit current.

12. Electronic device with an over-current protection circuit according to claim 1 .

13. The over-current protection circuit of claim 1 , the gate driver to control the on-off state of both the HEMT and the sense transistor based on a sense current from the sense transistor and a supply current from the HEMT.

14. An over-current protection circuit comprising:
a first die comprising a first integrated circuit, the first integrated circuit comprising a control circuit, the control circuit comprising a gate driver;
a second die comprising a second integrated circuit, the second integrated circuit comprising:
a supply current input;
a supply current output;
a current supply switch comprising
a first switch terminal coupled to the supply current input,
a second switch terminal coupled to the supply current output, and
a high electron mobility transistor (HEMT), wherein

the current supply switch provides an on-state, in which the current supply switch provides a conductive connection between the first switch terminal and the second switch terminal, and an off-state, in which the current supply switch interrupts the conductive connection between the first switch terminal and the second switch terminal; and
a switch control device including:
an operational amplifier having a first input terminal coupled to the second current electrode of the sense transistor a second input terminal coupled to the second switch terminal, and an output terminal;
a comparator transistor having a first current electrode coupled to the first in put terminal of the operational amplifier, a second current electrode, and a control electrode coupled to the output terminal of the operational amplifier; and
a comparator having an input terminal coupled to the second current electrode of the comparator transistor, and an output terminal coupled to the gate driver;
the switch control device arranged to control the current supply switch of an over-current protection device based on level of a supply current provided to the over-current protection circuit, and to control the current supply switch into the off-state if the supply current is larger than a limit current, and wherein the over-current protection circuit provides an instant reaction to the supply current being larger than the limit current based on the HEMT being a normally-on transistor; and

the over-current protection circuit is configured to receive a supply current via the supply current input and to provide the supply current via the supply current output if the current supply switch is in the on-state.

15. The over-current protection circuit of claim 14 , the control circuit further comprising:
a sensor current input to receive a sense current; and
a supply current input to receive the supply current from the second current electrode of the HEMT, wherein the control circuit compares the sense current with the supply current.

16. The over-current protection circuit of claim 14 , wherein the HEMT is a GaN transistor.

17. An over-current protection circuit comprising:
a first die comprising a first integrated circuit, the first integrated circuit comprising a control circuit, the control circuit comprising a gate driver;
a second die comprising a second integrated circuit, the second integrated circuit comprising:
a supply current input;
a supply current output;
a current supply switch comprising:
a first switch terminal coupled to the supply current input;
a second switch terminal couple

Assignees

• Renaud Philippe
• Dupuy Philippe
• Nxp Usa Inc

Inventors

• Renaud Philippe
• Dupuy Philippe

Classifications

• H02H3/02 Primary

  Details · CPC title

• H02H3/08 Primary

  responsive to excess current (responsive to abnormal temperature caused by excess current H02H5/04) · CPC title