Texas Instruments Corporation

Xiaowei Deng

Wah Kit Loh

Theodore Warren Houston

Anand Seshadri

Hugh Thomas Mair

Bryan David Sheffield

Luan A Dang

Terence G W Blake

David Barry Scott

Shyh-Horng Yang

Parvinder Kumar Rana

David J Toops

Zhonghai Shi

James D Gallia

Tito Gelsomini

George B Jamison

Yunchen Qiu

Lakshmikantha V Holla

Tam Minh Tran

Beena Pious

Xiaowei Zhu

Robin C Sarma

Jon Lescrenier

Yang Yi

In one example a semiconductor device has a data latch that includes first and second transmission gates and first and second inverters. The first inverter is connected between a first terminal of the first transmission gate and a first terminal of the second transmission gate. The second inverter is connected between a second terminal of the first transmission gate and a second terminal of the second transmission gate. The data latch is configured to store a datum received at the connection between the first transmission gate and the second inverter, and to store a datum received at the connection between the second transmission gate and the first inverter.

Sense amplifier look-through latch for FAMOS-based EPROM

A method of screening complementary metal-oxide-semiconductor CMOS integrated circuits, such as integrated circuits including CMOS static random access memory (SRAM) cells, for transistors susceptible to transistor characteristic shifts over operating time. For the example of SRAM cells formed of cross-coupled CMOS inverters, separate ground voltage levels can be applied to the source nodes of the driver transistors, or separate power supply voltage levels can be applied to the source nodes of the load transistors (or both). Asymmetric bias voltages applied to the transistors in this manner will reduce the transistor drive current, and can thus mimic the effects of bias temperature instability (BTI). Cells that are vulnerable to threshold voltage shift over time can thus be identified.

Array power supply-based screening of static random access memory cells for bias temperature instability

An SRAM with buffered-read bit cells is disclosed (FIGS.-). The integrated circuit includes a plurality of memory cells (). Each memory cell has a plurality of transistors (). A first memory cell (FIG.) is arranged to store a data signal in response to an active write word line (WWL) and to produce the data signal in response to an active read word line (RWL). A test circuit () formed on the integrated circuit is operable to test current and voltage characteristics of each transistor of the plurality of transistors of the first memory cell (FIGS.-).

SRAM with buffered-read bit cells and its testing

An integrated circuit containing a memory and a sense amplifier. The integrated circuit also containing an extended delay circuit which extends the delay between when a precharged bitline is floated and when a wordline is enabled. A method of testing an integrated circuit to identify bitlines with excessive leakage.

Bitline leakage detection in memories

A method of testing large-scale integrated circuits including multiple instances of memory arrays, and an integrated circuit structure for assisting such testing. In one embodiment, voltage drops due to parasitic resistance in array bias conductors are determined by extracting layout parameters, and subsequent circuit simulation that derives the voltage drops in those conductors during operation of each memory array. In another embodiment, sense lines from each memory array are selectively connected to a test sense terminal of the integrated circuit, at which the array bias voltage at each memory array is externally measured. Feedback control of the applied voltage to arrive at the desired array bias voltage can be performed.

Functional screening of static random access memories using an array bias voltage

An integrated circuit on-chip parametric (OCP) test structure includes a static random access memory (SRAM) universal test structure (UTS) having UTS ports and an OCP controller configured to determine first and second UTS ports of the SRAM UTS for independent connection to first and second on-chip test pads, respectively. The integrated circuit OCP test structure further includes a UTS OCP router connected to the OCP controller and configured to connect the first and second UTS ports of the SRAM UTS to the first and second on-chip test pads, respectively. Methods of operating an integrated circuit OCP test structure and OCP testing of an integrated circuit are also included.

Universal test structures based SRAM on-chip parametric test module and methods of operating and testing

A complementary metal-oxide-semiconductor (CMOS) static random access memory (SRAM) with no well contacts within the memory array. Modern sub-micron CMOS structures have been observed to have reduced vulnerability to latchup. Chip area is reduced by providing no well contacts within the array. Wells of either or both conductivity types may electrically float during operation of the memory. In other implementations, extensions of the array wells into peripheral circuitry may be provided, with well contacts provided in those extended portions.

Efficient static random-access memory layout

An integrated circuit including a complementary metal-oxide-semiconductor (CMOS) static random access memory (SRAM) with periodic deep well structures within the memory cell array. The deep well structures are contacted by surface well regions of the same conductivity type (e.g., n-type) in the memory cell array, forming two-dimensional grids of both n-type and p-type semiconductor material in the memory cell array area. Bias conductors may contact the grids to apply the desired well bias voltages, for example in well-tie regions or peripheral circuitry adjacent to the memory cell array.

Static random-access memory cell array with deep well regions

An embodiment of the invention provides a method for decreasing power in a static random access memory (SRAM). A first voltage is applied between latch sourcing and latch sinking supply lines for columns of memory cells that are column addressed during a read cycle. A second voltage is applied between latch sourcing and latch sinking supply lines for columns of memory cells that are not column addressed during a read cycle. Because the second voltage is less than the first voltage, power in the SRAM is reduced. In this embodiment, a memory cell in the SRAM includes at least one read buffer and a latch connected between the latch sourcing and latch sinking supply lines.

Reducing power in SRAM using supply voltage control

A solid-state memory in which each memory cell includes a cross-point addressable write element. Each memory cell includes a storage element, such as a pair of cross-coupled inverters, and a read buffer for coupling one of the storage nodes to a read bit line for the column containing the cell. The write element of each memory cell includes one or a pair of write select transistors controlled by a write word line for the row containing the cell, and write pass transistors connected to corresponding storage nodes and connected in series with a write select transistor. The write pass transistors are gated by a write bit line for the column containing the cell. In operation, a write reference is coupled to one of the storage nodes of a memory cell in the selected column and the selected row, depending on the data state carried by the complementary write bit lines for that column.

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Plano, TX, United States of America

Xiaowei Deng