VOLTAGE GENERATOR TO COMPENSATE FOR PROCESS CORNER AND TEMPERATURE VARIATIONS

• US 20170169867A1
• Filed: 05/11/2016
• Published: 06/15/2017
• Est. Priority Date: 12/11/2015
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Inventors: Nguyen, Hao, Mui, Man, DESAI, Amul, Kwon, Ohwon
• Granted Patent: US 9,959,915 B2
• Time in Patent Office: Days
• CPC Class Codes: G05F 1/463 Sources providing an output which depends on temperature
• CPC Class Codes: G11C 7/04 with means for avoiding disturbances due to temperature effects
• CPC Class Codes: G11C 7/08 Control thereof
• CPC Class Codes: G11C 7/10 Input/output [I/O] data interface arrangements, e.g. I/O data control circuits, I/O data buffers
• CPC Class Codes: G11C 7/1048 Data bus control circuits, e.g. precharging, presetting, equalising
• CPC Class Codes: G11C 7/106 Data output latches
• CPC Class Codes: G11C 7/12 Bit line control circuits, e.g. drivers, boosters, pull-up circuits, pull-down circuits, precharging circuits, equalising circuits, for bit lines
• CPC Class Codes: G11C 7/22 Read-write [R-W] timing or clocking circuits; Read-write [R-W] control signal generators or management
• CPC Class Codes: H01L 27/0211 adapted for requirements of temperature

Abstract

The present disclosure describes a system, a circuit, and method for process and temperature compensation in an integrated circuit. For example, the system includes a bus, a data latch, and a voltage generator. The data latch includes a plurality of transistors coupled to the bus. The voltage generator includes a tracking transistor with one or more physical characteristics that substantially match one or more respective physical characteristics—e.g., gate width and gate length dimensions—of at least one of the plurality of transistors in the data latch. The voltage generator is configured to adjust a pre-charged voltage on the bus based on an electrical characteristic of the tracking transistor.

Claims

1. A system comprising:

a bus;

a data latch comprising a plurality of transistors coupled to the bus; and

a voltage generator comprising a tracking transistor,

wherein one or more physical characteristics of the tracking transistor substantially match one or more respective physical characteristics of at least one of the plurality of transistors in the data latch, and

wherein the voltage generator is configured to adjust a pre-charged voltage on the bus based on an electrical characteristic of the tracking transistor.

2. The system of claim 1, wherein the system further comprises:

a sensing circuit coupled to the data latch via the bus, wherein the sensing circuit comprises a strobe transistor controlled by a strobe control signal, wherein the strobe control signal comprises a strobe control signal timing window based on a discharge rate of the pre-charged voltage, and wherein the discharge rate is based on the electrical characteristic of the tracking transistor.

3. The system of claim 1, wherein the voltage generator comprises an adjustable resistor circuit coupled to the tracking transistor and a current source, wherein the adjustable resistor circuit is configured to change a resistor value between the tracking transistor and the current source based on monitored temperature.

4. The system of claim 1, wherein the voltage generator is configured to lower the pre-charged voltage in response to an increase in temperature.

5. The system of claim 1, wherein the tracking transistor comprises a connection between a drain terminal of the tracking transistor and a gate terminal of the tracking transistor.

6. The system of claim 1, wherein the tracking transistor and the at least one of the plurality of transistors in the data latch are n-channel metal-oxide-semiconductor field-effect transistors.

7. The system of claim 1, wherein the at least one of the plurality of transistors in the data latch comprises a pass transistor for the data latch.

8. The system of claim 1, wherein the one or more physical characteristics of the tracking transistor comprise gate width and gate length dimensions.

9-14. -14. (canceled)

15. A method comprising:

generating, with a voltage generator, a pre-charged voltage on a bus coupled to a data latch; and

adjusting the pre-charged voltage based on temperature;

wherein the data latch comprises a plurality of transistors coupled to the bus, and

wherein the voltage generator comprises a tracking transistor, the tracking transistor comprising one or more physical characteristics that substantially match one or more respective physical characteristics of at least one of the plurality of transistors in the data latch.

16. The method of claim 15, further comprising:

discharging, with a sensing circuit, the pre-charged voltage via a strobe transistor controlled by a strobe control signal.

17. The method of claim 16, wherein the discharging the pre-charged voltage comprises storing, in the data latch, a voltage potential on the bus provided by the sensing circuit.

18. The method of claim 15, wherein the adjusting comprises lowering the pre-charged voltage in response to an increase in temperature.

19. The method of claim 15, wherein the tracking transistor and the at least one of the plurality of transistors in the data latch have the same device type.

20. The method of claim 15, wherein the one or more physical characteristics of the tracking transistor comprise gate width and gate length dimensions.

21. A circuit comprising:

data latch circuitry coupled to a source node; and

a voltage generator configured to produce a voltage potential on the source node, the voltage generator comprising,

adjustable resistance circuitry configured to provide a selected amount of resistance between the source node and a common node, and

a tracking transistor having a physical characteristic configured to correspond to a physical characteristic of the data latch circuitry,

wherein the voltage generator is configured to vary an amplitude of the voltage potential produced on the source node based an electrical characteristic of the tracking transistor.

22. The circuit of claim 21, wherein the physical characteristic of the tracking transistor is configured to correspond to a physical characteristic of a transistor of the data latch circuitry.

23. The circuit of claim 22, wherein the physical characteristic comprises one or more of a transistor dimension, a transistor gate dimension, a transistor gate width, a transistor type, a transistor process, and a transistor process corner.

24. The circuit of claim 21, wherein a first terminal of the tracking transistor is coupled to the common node, and wherein a second terminal of the tracking transistor is coupled to the source node and a gate terminal of the tracking transistor.

25. The circuit of claim 24, wherein the second terminal of the tracking transistor is coupled to the source node through the adjustable resistance circuitry, wherein the first terminal is coupled to a drain of the tracking transistor, and wherein the second terminal is coupled to a source of the tracking transistor.

26. The circuit of claim 21, wherein the voltage generator is configured to vary the amplitude of the voltage potential based on a temperature signal, the voltage generator further comprising:

a current source configured to generate a current, at least a portion of the current flowing through the adaptive resistance circuitry; and

temperature control circuitry configured select the amount of resistance provided by the adjustable resistance circuitry based on a temperature value.