Abstract: A hybrid write-assist memory system includes an array voltage supply and a static random access memory (SRAM) cell that is controlled by bit lines and a word line and employs a separable cell supply voltage coupled to the array voltage supply. Additionally, the hybrid write-assist memory system includes a supply voltage droop unit that is coupled to the SRAM cell and provides a voltage reduction of the separable cell supply voltage during a write operation. Also, the hybrid write-assist memory system includes a negative bit line unit that is coupled to the supply voltage droop unit and provides a negative bit line voltage concurrently with the voltage reduction of the separable cell supply voltage during the write operation. A method of operating a hybrid write-assist memory system is also provided.

Abstract: A configurable delay circuit and a method of clock buffering. One embodiment of the configurable delay circuit includes: (1) a first delay stage electrically couplable in series to a second delay stage, the first delay stage and the second delay stage each having an input port electrically coupled to a signal source, and (2) a delay path select circuit electrically coupled between the first delay stage and the second delay stage, and operable to select between a delay path including the first delay stage and another delay path including the first delay stage and the second delay stage.

Abstract: Small area low power data retention flop. In accordance with a first embodiment of the present invention, a circuit includes a master latch coupled to a data retention latch. The data retention latch is configured to operate as a slave latch to the master latch to implement a master-slave flip flop during normal operation. The data retention latch is configured to retain an output value of the master-slave flip flop during a low power data retention mode when the master latch is powered down. A single control input is configured to select between the normal operation and the low power data retention mode. The circuit may be independent of a third latch.

Abstract: Disclosed are devices, systems and/or methods relating to an eight transistor (8T) static random access memory (SRAM) cell, according to one or more embodiments. In one embodiment, an SRAM storage cell is disclosed comprising a word line, a write column select line, a cross-coupled data latch, and a first NMOS switch device serially coupled to a second NMOS switch device. In this embodiment, the gate node of the first NMOS switch device is coupled to the word line, a source node of the first NMOS switch device is coupled to the cross-coupled data latch, a gate node of the second NMOS switch device is coupled to the write column select line, and a source node of the second NMOS switch device is coupled to the cross-coupled data latch.

Abstract: A static random access memory (SRAM) cell is disclosed. The SRAM cell includes a storage unit configured to store a data bit in a storage node. The SRAM cell further includes an access unit coupled to the storage unit. The access unit is configured to transfer current to the storage node when a word line is asserted. The SRAM cell further includes a row header configured to provide current from a power supply when the word line is not asserted, and to not provide current from the power supply when the word line is asserted. The SRAM cell further includes a column header configured to provide current from a power supply when a write column line is not asserted, and to not provide current from the power supply when the write column line is asserted.

Abstract: A dual flip-flop circuit combines two or more flip-flip sub-circuits into a single circuit. The flip-flop circuit comprises a first flip-flop sub-circuit and a second flip-flop sub-circuit. The first flip-flop sub-circuit comprises a first storage sub-circuit configured to store a first selected input signal and transfer the first selected input signal to a first output signal when a buffered clock signal transitions between two different logic levels and a dock driver configured to receive a clock input signal, generate an inverted clock signal, and generate the buffered clock signal. The second flip-flop sub-circuit is coupled to the clock driver and configured to receive the inverted clock signal and the buffered clock signal. The second flip-flop sub-circuit comprises a second storage sub-circuit configured to store a second selected input signal and transfer the second selected input signal to a second output signal when the buffered clock signal transitions.

Abstract: Small area low power data retention flop. In accordance with a first embodiment of the present invention, a circuit includes a master latch coupled to a data retention latch. The data retention latch is configured to operate as a slave latch to the master latch to implement a master-slave flip flop during normal operation. The data retention latch is configured to retain an output value of the master-slave flip flop during a low power data retention mode when the master latch is powered down. A single control input is configured to select between the normal operation and the low power data retention mode. The circuit may be independent of a third latch.

Abstract: Mitigating external influences on long signal lines. In accordance with an embodiment of the present invention, a column of a memory array includes first and second transistors configured to pull up the bit line of the column. The column includes a third transistor configured to selectively pull up the bit line of the column responsive to a level of the inverted bit line of the column and a fourth transistor configured to selectively pull up the inverted bit line of the column responsive to a level of the bit line of the column. The column further includes fifth and sixth transistors configured to selectively pull up the bit line and inverted bit line of the column responsive to the clamp signal and a seventh transistor configured to selectively couple the bit line of the column and the inverted bit line of the column responsive to the clamp signal.

Abstract: A scan flip-flop circuit comprises a scan input sub-circuit and a selection sub-circuit. The scan input sub-circuit is configured to receive a scan input signal and a scan enable signal and, when the scan enable signal is activated, generate complementary scan input signals representing the scan input signal that are delayed relative to a transition of a clock input signal between two different logic levels. The selection sub-circuit is coupled to the scan input sub-circuit and configured to receive the complementary scan input signals and, based on the scan enable signal, output an inverted version of either the scan input signal or a data signal as a first selected input signal.

Abstract: A dual flip-flop circuit combines two or more flip-flip sub-circuits into a single circuit. The flip-flop circuit comprises a first flip-flop sub-circuit and a second flip-flop sub-circuit. The first flip-flop sub-circuit comprises a first storage sub-circuit configured to store a first selected input signal and transfer the first selected input signal to a first output signal when a buffered clock signal transitions between two different logic levels and a dock driver configured to receive a clock input signal, generate an inverted clock signal, and generate the buffered clock signal. The second flip-flop sub-circuit is coupled to the clock driver and configured to receive the inverted clock signal and the buffered clock signal. The second flip-flop sub-circuit comprises a second storage sub-circuit configured to store a second selected input signal and transfer the second selected input signal to a second output signal when the buffered clock signal transitions.

Abstract: In various embodiments, a memory cell and a memory are provided. The memory cell comprises a Static Random Access Memory (SRAM) cell including a reset-set (RS) flip-flop and a Read Only Memory (ROM) cell being connected (or coupled) to the SRAM cell to set logic states of internal latch nodes of the RS flip-flop when the ROM cell is triggered. The size of the memory cells proposed in an embodiment of the invention is much smaller than the sum of the size of ROM cells and the size of SRAM cells with the capacity of the memory cells same as the sum of the capacity of the ROM cells and the capacity of the SRAM cells.

Abstract: One embodiment of the present invention sets forth a technique for shifting the voltage level of signals from a low voltage domain to a high voltage domain, where VDDH is the supply voltage of the high voltage domain and VDDL is the supply voltage of the low voltage domain. A level shifting circuit uses a single input rather than dual rail inputs and does not produce a direct current flow in order to reduce the power consumption. The voltage level shifting circuit may also be used to shift a clock signal since the delays of the rising and falling edges of the clock signal are matched by using a delay element.

Abstract: An apparatus includes a single-rail input connected to a low-voltage domain and a voltage-transition circuit connected to the single-rail input. The voltage-transition circuit is configured to convert a voltage of the low-voltage domain received via the single-rail input to a voltage of the high-voltage domain.

Abstract: One embodiment of the present invention sets forth a technique for shifting the voltage level of signals from the high voltage domain to a low voltage domain, where VDD_IO is the supply voltage of the high voltage domain and VDD_Logic is the supply voltage of the low voltage domain. A level shifting circuit using a combination of I/O and logic transistors avoids exceeding a maximum tolerable voltage across the gate and source of any of the transistors. The level shifting circuit operates includes a reference voltage circuit that is independent of VDD_IO, so the same level shifting circuit may be used for various VDD_IO voltages. Additionally, the voltage level shifting circuit is not sensitive to scaling of VDD_Logic and operates properly when VDD_Logic is reduced due to shrinking silicon process technology and/or is reduced for a low power application.

Abstract: One embodiment of the present invention sets forth a sense amplifier flop design that is tolerant of process variation. Specific staging of signal transitions through the sense amplifier flop circuit eliminate operational phases involving short-circuit currents between n-channel field-effect transistors (N-FETs) and p-channel field effect transistors (P-FETs) in a complementary-symmetry metal-oxide semiconductor process. By eliminating short-circuit currents between N-FETs and P-FETs within the sense amplifier flop, a large variation in conductivity ratio between N-FETs and P-FETs may be tolerated by the sense amplifier flop. This tolerance to conductivity ratio translates to a tolerance for process variation by the sense amplifier flop circuit.

Abstract: Embodiments for an area efficient high performance memory cell comprising a transistor connected to one of a bit line and a bit line bar are disclosed.

Abstract: One embodiment of the present invention sets forth a synchronous two-port static random access memory (SRAM) design with the area efficiency of a one-port SRAM. By restricting both access ports to an edge-triggered, synchronous clocking regime, the internal timing of the SRAM can be optimized to allow high-performance double-pumped access to the SRAM storage cells. By double-pumping the SRAM storage cells, one read access and one write access are possible per clock cycle, allowing the SRAM to present two external ports, each capable of performing one transaction per clock cycle.

Abstract: One embodiment of the present invention sets forth an active bit line charge keeper circuit for improving the reliability of a static random access memory (SRAM) circuit. The active bit line charge keeper circuit includes two sub-circuits, each disposed between bit line pairs within the SRAM circuit. The first sub-circuit mitigates residual state associated with over-developed read state on the bit lines. The second sub-circuit mitigates the effects of residual state associated with reading one value on a given pair of bit lines and subsequently writing a different value. By mitigating the effects of residual state within an SRAM circuit, higher reliability at a given performance level may be achieved.

Abstract: An apparatus and method are provided for preventing a current leakage or direct current when a low voltage domain is powered down. Included is a voltage transition circuit connected between a low voltage domain and a high voltage domain. Such voltage transition circuit includes a circuit component for preventing a current leakage when the low voltage domain is powered down.

Abstract: One embodiment of the present invention sets forth a set of three building block circuits for designing a flexible timing generator for an integrated circuit. The first and second building blocks include delay elements that may be customized and fine-tuned prior to fabrication. The third building block may be tuned prior to fabrication as well as after fabrication. The three building blocks may be incorporated into a modular architecture, enabling designers to easily generate well-characterized, flexible, generic timer circuits.