Driver Circuit

• US 20130321035A1
• Filed: 05/28/2013
• Published: 12/05/2013
• Est. Priority Date: 05/29/2012
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Lagioia, Maria Giovanna, Pichler, Joachim, Bodano, Emanuele, Subotskaya, Volha
• Granted Patent: US 8,981,820 B2
• Time in Patent Office: Days
• US Class Current: 327/109
• CPC Class Codes: H03K 17/165 by feedback from the output circuit to the control circuit

Abstract

Devices and methods are provided in which a driver is supplied via a first current path and a second current path which can comprise a switching element.

Claims

1. A circuit, comprising:

a driver having an input, an output, a first supply terminal and a second supply terminal;

a first current path between a first supply voltage potential and the first supply terminal of the driver;

a second current path between the first supply terminal of the driver and the first supply voltage potential, wherein the second current path comprises a switching element configured to selectively activate and deactivate the second current path, and wherein the second supply terminal of the driver is coupled to a second supply voltage potential; and

a controller configured to drive the switching element to activate the second current path if a current through the driver reaches a predefined threshold value.

2. The circuit as claimed in claim 1, wherein the controller is further configured to drive the switching element to deactivate the second current path if the current through the driver falls below the predefined threshold value.

3. The circuit as claimed in claim 1,

wherein the first current path comprises a further switching element,

wherein the controller comprises a series circuit formed by a resistor and a scaled switching element, wherein the series circuit is connected in parallel with the second current path, and wherein the scaled switching element is a scaled version of the further switching element, and

wherein a control terminal of the switching element is coupled to a node between the resistor and the scaled switching element.

4. The circuit as claimed in claim 3, wherein the switching element comprises a P-type transistor, and wherein the further switching element and the scaled switching element comprise N-type transistors.

5. The circuit as claimed in claim 1, wherein the first current path comprises a further switching element.

6. The circuit as claimed in claim 5, wherein the controller is further configured to drive the further switching element in a manner dependent on a voltage at the first supply terminal of the driver and a reference voltage.

7. The circuit as claimed in claim 6, wherein the controller comprises an operational amplifier.

8. The circuit as claimed in claim 7, wherein a supply input of the operational amplifier is coupled to the first supply voltage potential via a charge pump.

9. The circuit as claimed in claim 1, further comprising a load switching element, wherein a control input of the load switching element is coupled to the output of the driver, and wherein the load switching element is connected in series with a load between the first supply voltage potential and the second supply voltage potential.

10. The circuit as claimed in claim 1,

wherein the first current path comprises a first N-type transistor,

wherein the switching element comprises a P-type transistor,

further comprising a series circuit formed by a resistor and a further N-type transistor, wherein a gate terminal of the P-type transistor is coupled to a node between the resistor and the further N-type transistor,

wherein a gate terminal of the N-type transistor and a gate terminal of the further N-type transistor are coupled to an output of an operational amplifier,

wherein a first input of the operational amplifier is coupled to a reference voltage input, and

wherein a second input of the operational amplifier is coupled to the first supply terminal of the driver.

11. A method, comprising:

supplying a driver via a first current path; and

selectively activating a second current path for supplying the driver if a current through the driver exceeds a predefined threshold current.

12. The method as claimed in claim 11, further comprising regulating the first and/or second current path for setting a voltage at the driver.

13. The method as claimed in claim 11, further comprising selectively deactivating the second current path if the current through the driver does not exceed the predefined threshold current.

14. A circuit, comprising:

a driver circuit configured to receive an input signal and output an output drive signal in response thereto, wherein the driver circuit further receives a supply signal at a supply terminal thereof;

a switching element configured to switch a load based on the output drive signal of the driver circuit;

a variable current path circuit configured to vary a supply current to the supply terminal of the driver circuit as a function of the current through the driver circuit.

15. The circuit as claimed in claim 14, wherein the variable current path circuit comprises:

a first current path configured to provide a regulated first current to the supply terminal of the driver circuit; and

a second current path configured to provide a regulated second current to the supply terminal of the driver circuit.

16. The circuit as claimed in claim 15, further comprising a controller configured to regulate the first current based on a voltage at the supply terminal of the driver circuit, thereby providing a voltage regulation thereat.

17. The circuit as claimed in claim 15, further comprising a controller configured to ascertain a current demand of the driver circuit and vary the second current in response thereto.

18. The circuit as claimed in claim 17, wherein the controller is configured to deactivate the second current path if the current demand falls below a predetermined threshold value.

19. The circuit as claimed in claim 18, wherein the controller comprises a difference amplifier configured to drive the first current path and the second current path based on a difference between a voltage at the supply terminal of the driver circuit and a reference voltage.