Driver device for transistors, and corresponding integrated circuit

Patent metadata

Field	Value
Publication number	US-9595947-B2
Application number	US-201514797571-A
Country	US
Kind code	B2
Filing date	Jul 13, 2015
Priority date	Sep 30, 2014
Publication date	Mar 14, 2017
Grant date	Mar 14, 2017

Abstract

A driver device is for switching on and off a transistor for supplying a load by driving a control electrode of the transistor. The driver device includes a first terminal connected to the control electrode of the transistor, a second terminal connected between the transistor and the load, and a current-discharge path coupled to the first terminal. The current-discharge path includes a diode and is activated when the transistor is switched off. The diode becomes non-conductive to interrupt the current-discharge path when the voltage on the second terminal reaches a threshold value.

First claim

That which is claimed is:

1. A driver device for switching on and off a transistor feeding a load by driving a control electrode of the transistor, the driver device comprising:
a first terminal coupled to the control electrode of the transistor;
a second terminal coupled between the transistor and the load; and
a current discharge path coupled to said first terminal and being activated when the transistor is switched off, said current discharge path comprising a diode to interrupt said current discharge path based on said second terminal having a voltage reaching a threshold;
with the transistor comprising a field effect transistor (FET) having a drain, and with said second terminal coupled to the drain of the FET, and with said current discharge path extending between said first and second terminals.

2. The driver device of claim 1 , wherein said current discharge path is coupled to a bias voltage, with the threshold being a function of the bias voltage.

3. The driver device of claim 2 , further comprising a current generator coupled to the bias voltage, with said current generator being configured to operate on a signal on said first terminal.

4. The driver device of claim 3 , wherein said current generator comprises a current mirror.

5. The driver device of claim 1 , wherein said current discharge path further comprises an electronic switch in series with said diode.

6. The driver device of claim 5 , further comprising a pair of main electronic switches alternatively switchable on and off for switching on and off the transistor, with said electronic switch in said current discharge path being coupled to one of said main electronic switches to be activated synchronously therewith.

7. The driver device of claim 1 , wherein said first and second terminals and said current discharge path are configured on an integrated circuit.

8. A driver device for switching on and off a transistor feeding a load coupled thereto, the transistor comprising a control terminal and a first conduction terminal coupled to the load, the driver device comprising:
a first terminal coupled to the control terminal of the transistor;
a second terminal coupled between the first conduction terminal of the transistor and the load; and
a current discharge path coupled to a bias voltage and to said first and second terminals and comprising
a diode to interrupt said current discharge path based on said second terminal having a voltage reaching a threshold, with the threshold being a function of the bias voltage and
an electronic switch coupled in series with said diode and configured to activate said current discharge path when the transistor is switched off.

9. The driver device of claim 8 , wherein the transistor comprises a field effect transistor (FET), with the control terminal forming a gate and the first conduction terminal forming a drain.

10. The driver device of claim 8 , further comprising a current generator coupled to the bias voltage, with said current generator being configured to operate on a signal on said first terminal.

11. The driver device of claim 10 , wherein said current generator comprises a current mirror.

12. The driver device of claim 8 , further comprising a pair of main electronic switches alternatively switchable on and off for switching on and off the transistor, with said electronic switch in said current discharge path being coupled to one of said main electronic switches to be activated synchronously therewith.

13. The driver device of claim 8 , wherein said first and second terminals and said current discharge path are configured on an integrated circuit.

14. A method for making a driver device for switching on and off a transistor feeding a load by driving a control electrode of the transistor, the method comprising:
coupling a first terminal to the control electrode of the transistor;
coupling a second terminal between the transistor and the load; and
coupling a current discharge path to the first terminal and being activated when the transistor is switched off, the current discharge path comprising a diode to interrupt the current discharge path based on the second terminal having a voltage reaching a threshold;
the transistor comprises a field effect transistor (FET) having a drain and a source, with the second terminal coupled to the drain of the FET, and with the current discharge path extending between the first and second terminals.

15. The method of claim 14 , wherein the current discharge path is coupled to a bias voltage, with the threshold being a function of the bias voltage.

16. The method of claim 15 , further comprising coupling a current generator to the bias voltage, with the current generator being configured to operate on a signal on the first terminal.

17. The method of claim 16 , wherein the current generator comprises a current mirror.

18. The method of claim 14 , wherein the current discharge path further comprises an electronic switch in series with the diode.

19. The method of claim 18 , further comprising coupling a pair of main electronic switches to the transistor, with the pair of main electronic switches alternatively switchable on and off for switching on and off the transistor, with the electronic switch in the current discharge path being coupled to one of the main electronic switches to be activated synchronously therewith.

20. A driver device for switching on and off a transistor feeding a load by driving a control electrode of the transistor, the driver device comprising:
a first terminal coupled to the control electrode of the transistor;
a second terminal coupled between the transistor and the load; and
a current discharge path coupled to a bias voltage and to said first terminal and being activated when the transistor is switched off, said current discharge path comprising a diode to interrupt said current discharge path based on said second terminal having a voltage reaching a threshold, with the threshold being a function of the bias voltage.

21. The driver device of claim 20 , further comprising a current generator coupled to the bias voltage, with said current generator being configured to operate on a signal on said first terminal.

22. The driver device of claim 21 , wherein said current generator comprises a current mirror.

23. The driver device of claim 20 , wherein said current discharge path further comprises an electronic switch in series with said diode.

24. The driver device of claim 23 , further comprising a pair of main electronic switches alternatively switchable on and off for switching on and off the transistor, with said electronic switch in said current discharge path being coupled to one of said main electronic switches to be activated synchronously therewith.

25. The driver device of claim 20 , wherein said first and second terminals and said current discharge path are configured on an integrated circuit.

26. A driver device for switching on and off a transistor feeding a load by driving a control electrode of the transistor, the driver device comprising:
a first terminal coupled to the control electrode of the transistor;
a second terminal coupled between the transistor and the load;
a current discharge path coupled to said first terminal and being activated when the transistor is switched off, said current discharge path comprising an electronic switch and a diode in series with said electronic switch to interrupt sai

Assignees

• St Microelectronics Srl

Inventors

• Poletto Vanni
• Milazzo Patrizia
• Lecce Sergio

Classifications

• H03K5/04 Primary

  by increasing duration; by decreasing duration · CPC title

• H03K17/166

  Soft switching · CPC title

• H03K19/0175

  Coupling arrangements; Interface arrangements (interface arrangements for digital computers G06F3/00, G06F13/00) · CPC title

• H03K17/04106

  in field-effect transistor switches (H03K17/0412, H03K17/0416 take precedence) · CPC title

• H03K17/04206

  in field-effect transistor switches · CPC title