DEVICE HAVING INTERNAL VOLTAGE GENERATING CIRCUIT

• US 20150338863A1
• Filed: 01/28/2015
• Published: 11/26/2015
• Est. Priority Date: 05/20/2014
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: IKEDA, YUTAKA
• Granted Patent: US 9,740,220 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G05F 1/461 using an operational amplifier as final control device
• CPC Class Codes: G05F 1/56 using semiconductor devices in series with the load as final control devices G05F1/461 takes precedence
• CPC Class Codes: G05F 1/575 characterised by the feedback circuit
• CPC Class Codes: G11C 5/147 Voltage reference generators, voltage or current regulators; Internally lowered supply levels; Compensation for voltage drops G11C5/141 takes precedence

Abstract

A device includes an amplifying circuit having first and second input terminals and an output terminal, a ground terminal, a variable resistance circuit, and a resistance selecting circuit coupled in series to the variable resistance circuit between the output terminal and the ground terminal. The resistance selecting circuit includes a first node coupled to the second input terminal, a plurality of resistors coupled in series to each other and a plurality of gate circuits each coupled between the first node and one end of a corresponding one of the resistors.

Claims

1. A device comprising:

an amplifying circuit having first and second input terminals and an output terminal;

a ground terminal;

a variable resistance circuit; and

a resistance selecting circuit coupled in series to the variable resistance circuit between the output terminal and the ground terminal, the resistance selecting circuit including a first node coupled to the second input terminal, a plurality of resistors coupled in series to each other and a plurality of gate circuits each coupled between the first node and one end of a corresponding one of the resistors.

2. The device as claimed in claim 1, further comprising a reference voltage generating circuit configured to supply a reference voltage to the first input terminal of the amplifying circuit, wherein the reference voltage is substantially stable regardless of a thermal change on the device.

3. The device as claimed in claim 1, further comprising:

a memory cell array operable by an internal voltage; and

an internal voltage generating circuit configured to generate the internal voltage based on a voltage supplied to the output terminal of the amplifying circuit.

4. The device as claimed in claim 1, wherein the plurality of gate circuits of the resistance selecting circuit are configured to be controlled to have a selected one of the gate circuits closed and the other or others of the gate circuits opened.

5. The device as claimed in claim 1, wherein the plurality of gate circuits of the resistance selecting circuit includes transistors coupled between the first node and the second nodes, respectively.

6. The device as claimed in claim 5, further comprising a code storing circuit configured to supply code signals to gates of the transistors, respectively.

7. The device as claimed in claim 1, wherein the variable resistance circuit is coupled between the output terminal and the resistance selecting circuit and the resistance selecting circuit is coupled between the variable resistance circuit and the ground terminal.

8. The device as claimed in claim 1, wherein the resistance selecting circuit is coupled between the output terminal and the variable resistance circuit and the variable resistance circuit is coupled between the resistance selecting circuit and the ground terminal.

9. The device as claimed in claim 7, further comprising an additional variable resistance circuit coupled between the resistance selecting circuit and the ground terminal.

10. A device comprising:

an amplifying circuit configured to be supplied with first and second voltages and to generate a third voltage responsive to a voltage comparison between the first and second voltages;

a variable resistance circuit configured to be supplied with the third voltage and to supply a fourth voltage different from the third voltage; and

a resistance selecting circuit configured to be supplied with the fourth voltage and to generate a plurality of internal voltages different from each other based on the fourth voltage, the resistance selecting circuit further configured to output a selected one of the internal voltages as the second voltage to the amplifying circuit.

11. The device as claimed in claim 10, further comprising a reference voltage generating circuit configured to generate a reference voltage that is substantially stable regardless of a thermal change on the device as the first voltage.

12. The device as claimed in claim 10, wherein the resistance selecting circuit includes a plurality of internal nodes to which the internal voltages are supplied, an output node to which the selected one of the internal voltages is supplied, and a plurality of gate circuits each coupled between a corresponding one of the internal nodes and the output node.

13. The device as claimed in claim 12, wherein the plurality of gate circuits are configured to be controlled such that a selected one of the plurality of gate circuits is closed and at least one of the other gate circuits of the plurality of gate circuits is opened.

14. The device as claimed in claim 10, wherein the resistance selecting circuit is further configured to supply a fifth voltage different from the fourth voltage and the device further comprises an additional variable resistance circuit configured to be supplied with the fifth voltage and a ground voltage.

15. The device as claimed in claim 14, wherein the variable resistance circuit and the additional variable resistance element are configured to be controlled such that a sum of resistance values of the variable resistance circuit and the additional variable resistance circuit is substantially stable.

16. A device comprising:

first, second, third and fourth nodes;

a first resistive element coupled between the first and second nodes;

a second resistive element coupled between the second and third nodes;

a first switch coupled in parallel to the first resistive element; and

a second switch coupled between the second and fourth nodes.

17. The device as claimed in claim 16, further comprising:

a fifth node; and

a third switch coupled between the third and fourth nodes.

18. The device as claimed in claim 17, further comprising:

a fourth switch coupled between the fourth and fifth nodes.

19. The device as claimed in claim 17, further comprising:

a fourth resistive element coupled in series to the first resistive element between the first and second nodes; and

a fifth switch coupled in parallel to the fourth resistive element.

20. The device as claimed in claim 19, further comprising an amplifying circuit including a first input terminal supplied with an input voltage, a second input terminal coupled to the fourth node, and an output terminal coupled to the first node.