CURRENT GENERATION CIRCUIT

• US 20140152106A1
• Filed: 10/02/2013
• Published: 06/05/2014
• Est. Priority Date: 12/03/2012
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Park, Sang Gyu, Kwon, Soon-Myung
• Granted Patent: US 9,466,986 B2
• Time in Patent Office: Days
• US Class Current: 307/52
• CPC Class Codes: G05F 3/242 with compensation for device parameters, e.g. channel width modulation, threshold voltage, processing, or external variations, e.g. temperature, loading, supply voltage
• CPC Class Codes: H02J 4/00 Circuit arrangements for mains or distribution networks not specified as ac or dc

Abstract

A current generating circuit that includes a first current source that generates a first current having a negative temperature coefficient a second current source that generates a second current having a positive temperature coefficient. A compensation circuit generates a common current using a first transistor that receives the first current and a second transistor formed in a mirroring structure, a third transistor that receives the second current, and a fourth transistor formed in a mirroring structure. In addition, the compensation circuit provides the common current as an output current using a transistor that is formed in at least a pair of mirroring structures.

Claims

1. A constant current generating circuit, comprising:

a first current source that generates a first current that has a negative temperature coefficient;

a second current source that generates a second current that has a positive temperature coefficient; and

a compensation circuit that generates a common current using a first transistor that receives the first current and a second transistor formed in a mirroring structure, a third transistor that receives the second current, and a fourth transistor formed in a mirroring structure, wherein the compensation circuit provides the common current as an output current using a transistor formed in at least a pair of mirroring structures.

2. The current generating circuit of claim 1, wherein a current amount of the first current and a current amount of the second current are adjusted between the first transistor and the second transistor and between the third transistor and the fourth transistor, respectively using a width/length (W/L) ratio of the transistor.

3. The current generating circuit of claim 1, wherein the common current has a corresponding temperature coefficient within a predetermined error range in an intermediate value of the negative temperature coefficient and the positive temperature coefficient.

4. The current generating circuit of claim 1, wherein the first transistor, the second transistor, the third transistor, and the fourth transistor are metal-oxide-semiconductor field-effect transistors (MOSFET) of an N-type channel.

5. The current generating circuit of claim 1, wherein the common current is transferred to a transistor formed in a pair of mirroring structures to adjust a current amount thereof, wherein the output current is a source current.

6. The current generating circuit of claim 5, wherein the transistor that is formed in the pair of mirroring structures controls a current amount of a common current provided to the output current by adjusting a width/length (W/L) ratio of a transistor that has a gate connected to a gate of a transistor in which the common current is transferred based on a W/L ratio of a transistor.

7. The current generating circuit of claim 5, wherein the transistor that is formed in the pair of mirroring structures is a metal-oxide-semiconductor field-effect transistor (MOSFET) of a P-type channel.

8. The current generating circuit of claim 1, wherein the common current is transferred to a transistor formed in two pairs of mirroring structures to adjust a current amount thereof, wherein the output current is a sink current.

9. The current generating circuit of claim 8, wherein the transistor that is formed in the two pairs of mirroring structures includes:

a first pair of transistors to which the common current is transferred; and

a second pair of transistors that output the output current,

wherein the first pair of transistors are metal-oxide-semiconductor field-effect transistors (MOSFET) of a P-type channel, and the second pair of transistors are MOSFET transistors of an N-type channel.

10. The current generating circuit of claim 9, wherein two transistors of a mirroring structure of the first pair of transistors and the second pair of transistors, respectively control a current amount that flows to the transistor by adjusting a width/length (W/L) ratio between two transistors of the mirroring structure.

11. The current generating circuit of claim 9, wherein each of sources of the first pair of transistors are connected to a first power source that applies a predetermined level constant voltage, and each of sources of the second pair of transistors apply a constant voltage of a level lower than the level constant voltage or is connected to a second power source that has a ground potential.

12. A constant current generating circuit, comprising:

a first current source that generates a first current having a negative temperature coefficient;

a second current source that generates a second current having a positive temperature coefficient; and

a compensation circuit connected to the first current source and the second current source to receive the first current and the second current and is configured to generate a predetermined constant third current that has a substantially small temperature coefficient insensitive to a temperature change.

13. The constant current generating circuit of claim 12, wherein the constant current has a reduced temperature coefficient when a temperature coefficient of each current transferred from the first current second and the second current source is supplemented.