High speed latch circuits using gated diodes

• US 7,242,629 B2
• Filed: 07/24/2006
• Issued: 07/10/2007
• Est. Priority Date: 09/03/2004
• Status: Expired due to Fees

• Current Assignee: GlobalFoundries, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Dennard, Robert H., Chang, Leland, Luk, Wing K., Montoye, Robert
• Primary Examiner(s): Hoang; Huan
• Assistant Examiner(s): PHAM, LY D
• Application Number:
  US11/491,701
• Publication Number:
  US 20060255850A1
• Time in Patent Office: 351 Days
• Field of Search: 327/51, 327/52, 327/57, 327/61, 365/205, 365/207, 365/189.05, 330/252, 330/287
• US Class Current: 365/205
• CPC Class Codes: G11C 7/06 Sense amplifiers; Associated circuits , e.g. timing or triggering circuits
• CPC Class Codes: G11C 7/065 Differential amplifiers of latching type
• CPC Class Codes: H03F 1/56 Modifications of input or output impedances, not otherwise provided for
• CPC Class Codes: H03F 2200/183 the amplifier comprising a gated diode
• CPC Class Codes: H03F 3/10 with diodes parametric amplifiers H03F7/00
• CPC Class Codes: H03F 3/347 in integrated circuits

Abstract

A sense amplifier circuit comprises (1) an isolation device comprising a control terminal and first and second terminals, the first terminal of the isolation device coupled to a signal line, (2) a gated diode comprising first and second terminals, the first terminal of the gated diode coupled to the second terminal of the isolation device, and the second terminal of the gated diode coupled to a set line; and (3) control circuitry coupled to the control terminal of the isolation device and adapted to control voltage on the control terminal of the isolation device in order to enable and disable the isolation device. A latch circuit further comprises a precharge device comprising a control terminal and first and second terminals, the first terminal of the precharge device coupled to a power supply voltage, and the second terminal of the precharge device coupled to the first terminal of the isolation device.

Claims

1. A latch circuit comprising:

a pass device comprising a control terminal and first and second terminals, the first terminal of the pass device coupled to a signal line, the control terminal of the pass device coupled to a first clock line;

a precharge device comprising a control terminal and first and second terminal, the control terminal of the precharge device coupled to a second clock line, the first terminal of the precharge device coupled to a power supply voltage, and the second terminal of the precharge device coupled to the first terminal of the pass device;

a gated diode comprising first and second terminals, the first terminal of the gated diode coupled to the second terminal of the pass device, and the second terminal of the gated diode coupled to a third clock line; and

an output device comprising an input and an output, the input of output device coupled to the first terminal of the gated diode and to the second terminal of the pass device, the output of the output device adapted to be the output of the latch circuit, the output device adapted to produce an output signal on the output of a sense amplifier circuit based on a voltage on the first terminal of the gated diode;

wherein the signal line is adapted to be coupled to an input signal.

2. The latch of claim 1, wherein the gated diode comprises a Metal Oxide Semiconductor Field Effect Transistor (MOSFET), and wherein the MOSFET is formed with at least one deep source/drain region but without any source/drain extensions or halos.

3. The latch circuit of claim 1, wherein the second and third clock lines are adapted to be coupled to a clock signal and wherein the first clock line is adapted to be coupled to a complemented version of the clock signal.

4. The latch circuit of claim 3, the wherein precharge device and the pass device each comprises a P-type Field Effect Transistor (PFET) and wherein the gated diode comprises a P-type device.

5. The latch circuit of claim 1, wherein the output device comprises an inverter comprising a P-type Field Effect Transistor (PFET) and an N-type Field Effect Transistor (NFET).

6. The latch circuit of claim 5, wherein:

the PFET comprises a control terminal and first and second terminals, the control terminal of the PFET coupled to the first terminal of the gated diode, the first terminal of the PFET coupled to a power supply voltage, and the second terminal of the PFET coupled to a first terminal of the NFET; and

the NFET comprises a control terminal, the first terminal and a second terminal, the control terminal of the NFET coupled to the first terminal of the gated diode, and the second terminal of the NFET coupled at ground;

wherein the first terminal of the NFET comprises the output of the output device.

7. The latch circuit of claim 1, wherein the first, second and third clock lines are adapted to be coupled to a single clock signal.

8. The latch circuit of claim 7, wherein precharge device comprises a P-type Field Effect Transistor (PFET), wherein the pass device comprises an N-Type FET (NFET) and wherein the gated diode comprises a P-type device.

9. The latch circuit of claim 1, further comprising a keeper device comprising a control terminal and first and second terminals, the control terminal of the keeper device coupled to the output of the latch circuit, the first terminal of the keeper device coupled to the voltage supply, and the second terminal of the keeper device coupled to the first terminal of the gated diode.

10. The latch circuit of claim 9, wherein the keeper comprises a P-type Field Effect Transistor (PFET).

11. The latch circuit of claim 1, wherein the first clock line coupling the output of the latch circuit with the control terminal of the pass device and wherein the pass device comprises a P-type Field Effect Transistor (PFET).

12. The latch circuit of claim 11, wherein the latch circuit further comprises a protection diode having a control terminal and an output terminal, output device is coupled to the voltage source and to ground, the control terminal of the protection diode is coupled to ground and the output terminal of the protection diode is coupled to the first terminal of the gated diode.

13. The latch circuit of claim 12, wherein the protection diode comprises an N-type FET (NFET) comprising the control terminal and first and second terminals, the first terminal of the NFET of the protection diode being the output terminal of the protection diode, and the second terminal of the NFET of the protection diode coupled to the control terminal of the NFET of the protection diode.

14. The latch circuit of claim 1, wherein the first clock line comprises a line coupling the output of the latch circuit with the control terminal of the pass device, the pass device comprises a P-type Field Effect Transistor (PFET), the pass device further comprises an N-type Field Effect Transistor (NFET) in parallel with the PFET, the NFET comprising a control terminal and first and second terminal, the control terminal of the NFET coupled to the third clock line, the first terminal of the NFET coupled to the signal line, and the second terminal of the NFET coupled to the first terminal of the gated diode.

15. A semiconductor comprising at least one latch circuit, each of the at least one latch circuits comprising:

a pass device comprising a control terminal and first and second terminal, the first terminal of the pass device coupled to a signal line, the control terminal of the pass device coupled to a first clock line;

a precharge device coupled to a power supply voltage, and the second terminal of the precharge the control terminal of the precharge device coupled to a second clock line, the first terminal of the precharge device coupled to a power supply voltage, and the second terminal of the precharge device couple to the first terminal of the pass device;

a gated diode comprising first and second terminals, the first terminal of the gated diode coupled to the second terminal of the pass device, and the terminal of the gated diode coupled to a third clock line; and

an output device comprising an input and an output, the input of the output device coupled to the first terminal of the gated diode and to the second terminal of the pass device, the output of the output device adapted to be the output of the latch circuit, the output device adapted to produce an output signal on the output of the sense amplifier circuit based on a voltage on the first terminal of the gated diode;

wherein the signal line is adapted to be coupled to an input signal.