Synopsys, Inc.

Stmicroelectronics International N.v.

Vinay Kumar

Kedar Janardan Dhori

Ashish Kumar

Shishir Kumar

Sudhir Kumar

Amit Khanuja

Harsh Rawat

Ravindra Kumar Shrivastava

Saurabh Porwal

Neeraj Kapoor

Nikhil Puri

PraveenKumar Verma

Madhav Mansukh Padaliya

Sumit Srivastava

A memory device includes a plurality of select lines, a plurality of word lines, an array of memory cells, a bitline, and a resistance device. The array of memory cells includes multiple rows and multiple columns. The bitline is structured to receive a current in a read operation, causing a value stored in a selected memory cell to be readable when a select line and a word line that interest the selected memory cell are selected. The resistance device has a first terminal and a second terminal. The first terminal is coupled to the select lines, and the second terminal is coupled to ground. The resistance device is structured to bias, in the read operation, word lines of unselected memory cells in a column of a selected memory cell to a determined negative voltage.

Reducing memory device bitline leakage

A delay circuit. In some embodiments, a non-transitory computer readable medium includes stored instructions, which when executed by a processor, cause the processor to generate a digital representation of a circuit including: a first inverter, having an input, an output, and two power supply connections; a first current source, electrically coupled in series between a power supply conductor and a power supply connection of the two power supply connections of the first inverter; and a ramp generator circuit, electrically coupled to the input of the first inverter.

Delay circuit

A memory device includes bitcells connected to wordlines and bitlines, and driver circuitry that updates the bitcells. The driver circuitry includes first transistors, and a first inverter device. The first transistors drive a bitcell of a memory device. The first inverter device is coupled to the first transistors, and drives the first transistors with a first control signal. The first inverter device includes first inverter circuitry and second inverter circuitry. The first inverter circuitry receives a first signal, a first voltage, and a second voltage differing from the first voltage, and generates a first inverted signal based on the first signal, the first voltage and the second voltage. The second inverter circuitry receives the first inverted signal, the second voltage and a third voltage differing from the second voltage, and generates the first control signal based on the first inverted signal, the third voltage and the second voltage.

Reducing spurious write operations in a memory device

A static random access memory (SRAM) system includes a plurality of SRAM storage cells, each of the plurality of SRAM storage cells coupled to a respective read bit line, and a dynamic keeper coupled to the read bit line. The dynamic keeper includes a first keeper to support a read operation at a first temperature range, and a second keeper to support the read operation at a second temperature range, and a temperature-sensitive control circuit to select the first keeper or the second keeper based on temperature.

Temperature tracked dynamic keeper implementation to enable read operations

A memory array including a plurality of memory cells and a plurality of drivers is disclosed. The plurality of memory cells may be arranged in a plurality of rows and a plurality of columns. Memory cells corresponding to a row of the plurality of rows may be logically grouped into a plurality of memory array segments. The plurality of drivers may be coupled to corresponding first ends of corresponding memory array segments of the plurality of memory array segments. Second ends of the corresponding memory array segments may be coupled to second ends of corresponding adjacent memory array segments of the plurality of memory array segments. The second ends of the corresponding memory array segments and the second ends of corresponding adjacent memory array segments may be coupled to corresponding wordlines of a plurality of wordlines.

Area efficient and high-performance wordline segmented architecture

PMOS-based temperature compensated read-assist circuits for low-Vmin 6T SRAM bitcells realized in nanometer scale (e.g., 7 nm) CMOS FinFET technologies generate maximum wordline lowering (lower wordline voltages) at higher temperatures and minimum wordline lowering (higher wordline voltages) at lower operating temperatures in way that is substantially process independent and avoids post-silicon tuning. A read-assist PMOS transistor is connected between an associated wordline and VSS and controlled by a temperature compensation signal produced at an intermediate node between weak pull-up and strong pull-down PMOS transistors that are connected in series between VDD and VSS and respectively controlled by VDD and VSS during read operations. This configuration generates the temperature compensation signal at a level closer to VSS at high temperatures than at low temperatures, whereby write-ability is not impacted by the read-assist circuit at low temperature. An optional actuation circuit disables the temperature compensation circuit during non-active cycles to prevent current leakage.

Performance aware word line under-drive read assist scheme for high density SRAM to enable low voltage functionality

A reliability aware negative bit-line write assist (RA-NBL) circuit comprises a coupling capacitor to provide a negative bump for write assist, and a control input generator control charging of the coupling capacitor, such that the negative bump is high at a low voltage, and the negative bump is low at a high voltage.

Robust negative bit-line and reliability aware write assist

Read stability of a memory is enhanced in low voltage operation mode by selectively boosting a cell supply voltage for a row of memory cells. The boosted voltage results from a capacitive coupling to the word line in that row. The capacitive coupling is implemented by running the metal line of the power supply line for the cell supply voltage and the metal line for the word line adjacent to each other in a common metallization level. The selective voltage boost is controlled in response to operation of a modified memory cell exhibiting a deteriorated write margin. An output of the modified memory cell is compared to a threshold to generate a signal for controlling the selective voltage boost. Word line under-voltage circuitry is further provided to control application of an under-voltage to the word line.

Method and apparatus for enhancing read stability of a static random access memory circuit in low voltage operation

A sense amplifier enable signal generating circuit includes an input coupled to a dummy bit line of a memory. A voltage comparator circuit compares a voltage on the dummy bit line to a threshold voltage and generates an output signal when the voltage falls below that threshold voltage. A multi-bit counter circuit counts a count value in response to the output signal. A pull-up circuit pulls up the voltage on the dummy bit line in response to the output signal. A count comparator circuit compares the count value to a count threshold and generates a sense amplifier enable signal when the count value equals the count threshold.

Circuit for generating a sense amplifier enable signal with variable timing

Repair control logic for a safe memory having redundant elements is provided. The repair control logic includes comparison logic including, for each bit slice of a memory array, a comparator circuit configured to determine whether a location value of an associated bit slice of the memory array is greater than a location value of a defective bit slice of the memory array, and data switching logic including, for each bit slice of the memory array, a switching circuit, responsive to a determination that the location value of the associated bit slice is greater than the location value of the defective bit slice, to switch data from the associated bit slice to an adjacent bit slice of the memory array.

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Aligarh, India

Vinay Kumar