Granted Patent B2

US 7,545,694 · App. 11/839,632 · Granted Jun 9, 2009

Abstract

Claims (37)

1. A circuit, comprising:

a configuration selector comprising a read amplifier, a debug circuit and a backup read circuit;

a controllable input node comprising an enabling circuit, the controllable input node coupled to the configuration selector; and

a differential signal generator comprising a reference signal source, the differential signal generator is coupled to the controllable input node,

wherein said configuration selector is operable to selectively couple a signal to disable data latching and further operable to enable linear amplification in a storage cell responsive to a delayed generation of different signals generated by said differential signal generator.

2. The circuit of claim 1 , wherein the configuration selector comprises:

a plurality of transistors further comprising a plurality of Metal Oxide Semiconductor (MOS) transistors;

a plurality of cross coupled transmission gates coupled to the plurality of transistors in a positive feedback configuration; and

an inverter selectively coupled to the plurality of cross coupled transmission gates, in a latch enable configuration and in a linear enable configuration.

3. The circuit of claim 2 , wherein the plurality of cross coupled transmission gates is coupled to:

a control node comprising a gate terminal of a MOS transistor;

an input node; and

an output node of the plurality of transistors.

4. The circuit of claim 1 , wherein the controllable input node comprises:

a plurality of input transistors coupled to a plurality of differential input signals from the differential signal generator; and

an enabling transistor coupled to a common input node of the plurality of input transistors.

5. The circuit of claim 4 , wherein the enabling transistor is coupled to a latch sense enable signal at a gate terminal.

6. The circuit of claim 1 , wherein the differential signal generator comprises a current to voltage converter.

7. The circuit of claim 6 , wherein the current to voltage converter comprises a differential amplifier further comprising a plurality of input current terminals and a plurality of output voltage terminals.

8. The circuit of claim 1 , further comprising a multiple mode differential amplifier unit.

9. A method, comprising:

generating differential signals responsive to a comparison between a reference signal and a data storage value;

enabling data latching in a storage cell;

disabling data latching and enabling linear amplification in the storage cell responsive to a delayed generation of differential signals; and

enabling memory array leakage characterization.

10. The method of claim 9 , wherein the step of generating differential signals responsive to the comparison between the reference signal and the data storage value comprises generating a differential voltage.

11. The method of claim 9 , wherein the step of comparison between the reference signal and the data storage value comprises comparing a reference current with a memory cell current.

12. The method of claim 9 , wherein the step of enabling data latching in the storage cell comprises:

developing a differential voltage corresponding to a digital logic value;

latching the differential voltage corresponding to the digital value; and

amplifying the latched differential voltage to a digital output.

13. The method of claim 9 , wherein the step of disabling data latching in the storage cell responsive to the delayed generation of differential signals comprises enabling linear sensing of differential voltage to thereby initiate debug.

14. The method of claim 9 , wherein the step of enabling memory array leakage characterization comprises:

establishing a leakage current reference;

comparing a memory array leakage value with the established leakage current reference;

regenerating differential signals; and

enabling linear differential sensing for characterizing a memory array leakage current.

Assignments (8)