Arm Limited

Nicolaas Klarinus Johannes Van Winkelhoff

Bastien Jean Claude Aghetti

Bo Zheng

Fakhruddin Ali Bohra

Lalit Gupta

El Mehdi Boujamaa

Christophe Denis Lucien Frey

Sebastien Nicolas Ricavy

Yannick Marc Nevers

Nimish Sharma

Mikael Brun

Ali Alaoui

Pierre Lemarchand

Gerald Jean Louis Gouya

Denis René André Dufourt

Andy Wangkun Chen

Cyrille Nicolas Dray

Virgile Javerliac

Jungtae Kwon

Hsin-Yu Chen

Vincent Philippe Schuppe

Hetansh Pareshbhai Shah

Stephane Zonza

Durgesh Kumar Dubey

Ashish Bhardwaj

Cédric Sacha Redeau

Various implementations described herein refer to a method for providing memory with one or more banks. The method may include coupling read-write column multiplexer circuitry to the memory via bitlines including coupling a write column multiplexer to the bitlines for write operations and coupling a read column multiplexer to the bitlines for read operations. The method may include performing concurrent read operations and write operations in the one or more banks of the memory with the write column multiplexer and the read column multiplexer via the bitlines.

Concurrent memory access operations

Various implementations described herein refer to an integrated circuit having a memory cell array with a first number of rows and a second number of rows. The integrated circuit may include a first pre-decoder that receives a row address and selects a first row from the first number of rows based on the row address. The integrated circuit may include a second pre-decoder that receives the row address from the first pre-decoder and selects a second row from the second number of rows based on the row address received from the first pre-decoder. The integrated circuit may include a single row decoder that receives the row address and selects either the first row or the second row based on a row selection bit from the row address.

Wordline decoder circuitry

Various implementations described herein refer to a method for providing single port memory with a bitcell array arranged in columns and rows. The method may include coupling a wordline to the single port memory including coupling the wordline to the columns of the bitcell array. The method may include performing multiple memory access operations concurrently in the single port memory including performing a read operation in one column of the bitcell array using the wordline while performing a write operation in another column of the bitcell array using the wordline, or performing a write operation in one column of the bitcell array using the wordline while performing a read operation in another column of the bitcell array using the same wordline.

System device and method for providing single port memory access in bitcell array by tracking dummy wordline

Various implementations described herein are directed to an implementation of a higher order multiplexer using lower order multiplexers. In an embodiment, the implementation requires a slight modification to the existing circuitry design of the lower multiplexers. A plurality of multiplexers may be coupled with each other such that a common input port and output port is formed. Using an enable signal, only one of the coupled multiplexers may be enabled at a time while the remaining multiplexers are switched off. Therefore, upon receiving a select signal indicating an address of a memory cell, the lower multiplexers coupled together function as a higher order multiplexer in selecting the appropriate column corresponding to the memory cell.

Circuit architecture to derive higher mux from lower mux design

Various implementations described herein are directed to a device having memory circuitry with a core array of bitcells. The device may include write assist circuitry having passgates coupled to the bitcells via bitlines. The passgates may include a first passgate coupled to the bitcells via a first bitline and a second passgate coupled to the bitcells via a second bitline, and a gate of the second passgate may be coupled to the first bitline.

Write assist circuitry

A memory, a data processing system comprising a memory, a method of operating a memory and a memory compiler apparatus and method of memory compilation are provided, which relate to a memory comprising data storage circuitry to store data values at data locations. Addressing circuitry is provided to access the data value at a storage location in dependence on a received address and readout circuitry to provide an output value in dependence on the accessed data value. The memory further comprises scrambling circuitry to select at least one of: a mapping between the address and the storage location; and a mapping between the data value and the output value, in dependence on a received scrambling value. The mapping between the address and the storage location and/or the data value and the output value can thus be easily and rapidly changed.

Dynamic memory scrambling

Various implementations described herein are directed to a circuit for memory applications. The circuit may include a data storage structure having column multiplexor transistors coupled to complementary bitlines. The circuit may include a wordline shape enhancer having a pair of passgate transistors coupled between the complementary bitlines and a capacitive load.

Wordline shape enhancer

A memory protection device for controlling access to a memory and a method of controlling access to a memory are disclosed. A memory status value held by latch circuitry in the memory protection device determines whether the memory is an enabled or a disabled state. After power-up, a power-on-reset signal causes the memory status value to indicate the enabled state. In response to the assertion from a received control signal a memory kill signal is generated by the memory protection device which causes the memory status value to switch to its disabled state and the memory status value then cannot be changed back to the enabled state without a power reset. The memory status value being in the disabled state causes enable signal generation circuitry of the memory to openly be able to generate its read enable signal and write enable signal in a disabled state, thus preventing access to the memory.

Controlling access to a memory

The present invention provides an apparatus and method for erasing data in a memory device comprising an array of memory cells, and configured to operate from a clock signal. The apparatus includes erase circuitry, responsive to receipt of an erase signal in an asserted state, to perform a forced write operation independently of the clock signal in respect of each memory cell within a predetermined erase region of said array. Further, erase signal generation circuitry is configured to receive a control signal and to maintain said erase signal in a deasserted state provided that the control signal takes the form of a pulse signal having at least a predetermined minimum frequency between pulses. The erase signal generation circuitry is further configured to issue said erase signal in said asserted state if the control signal does not take the form of said pulse signal. Such an approach enables the security of a memory device to be improved, and in particular prevents hackers from taking advantage of data remanence effects, by ensuring that stored data is overwritten in an efficient, and clock independent, manner, triggered by assertion of an erase signal generated if a pulse-based control signal does not take it is expected form.

Apparatus and a method for erasing data stored in a memory device

A memory device including an array of memory cells arranged as a plurality of rows and columns. Write circuitry then controls a voltage level of the associated at least one bit line for each of the addressed memory cells to cause write data to be written into the addressed memory cells. In the presence of an asserted erase signal, a decoder circuitry's operation is modified such that it issues, independently of the clock signal, an asserted word line signal on the word line associated with each row in a predetermined erase region of the array. Further, the write circuitry's operation is modified so that it controls the voltage level of the associated at least one bit line for each memory cell in the predetermined erase region, in order to cause erase write data to be written into the memory cells of the predetermined erase region.

Memory device and a method for erasing data stored in the memory device

A functional circuit is coupled to a power supply conductor by at least one power gating transistor. A switching device applies a gate drive voltage to a gate terminal of the power gating transistor via a resistive element. The power gating transistor provides a Miller capacitance between its drain and gate terminals. The Miller capacitance, the resistance of the resistive element, and the drive strength of the switching device are configured such that, in response to the switching device switching the gate drive voltage to allow more current to pass through the power gating transistor, the Miller capacitance provides a feedback mechanism competing against the switching device to reduce the slew rate of the gate drive voltage such that the current passing between the power gate supply conductor and the functional circuit through the power gating transistor is less than the saturation current of the power gating transistor.

Power gating circuit

Memory circuitryincludes a memory cellcoupled to a plurality of bit line pairsproviding multiple access ports. Write boost circuitryserves to increase a write voltage applied to write a data value into the memory cell during at least a boost period of a write access. Collision detection circuitrydetects when the write access at least partially overlaps in time with a read access. If a collision is detected, then write assist circuitry serves to drive the bit line pair of the detected read access with a write assist voltage difference having the same polarity as the write voltage and a magnitude less than the write voltage with the boost voltage applied. The write assist circuitry drives the bit line pair of the colliding read independently of the write boost circuitry applying the boost voltage such that the boost voltage is undiminished by the action of the write assist circuitry.

Memory circuitry with write boost and write assist

An integrated circuit and method includes retention voltage generation circuitry which receives a supply voltage from a supply voltage node and provides a retention voltage. Functional circuitry is connected between the retention voltage node and a reference voltage node and is held in a data retention state when at least a minimum voltage is provided between the retention voltage node and the reference voltage node. Each of the circuits includes at least one p-type threshold device and at least one n-type threshold device, both having a characteristic threshold voltage. The p-type and n-type threshold devices are connected in parallel between the supply voltage node and the retention voltage node. A variation in the characteristic threshold voltage of either of the at least one p-type or the at least one n-type device maintains at least the minimum voltage between the retention voltage node and the reference voltage node.

Retention voltage generation

A timing control circuit comprises at least three current control units coupled in parallel between a first circuit and a second circuit node. The current control units each have an active mode and an inactive mode. The current control units are responsive to a timing trigger event to pass current whose magnitude is dependent on how many of the current control units are in the active mode. The current control units comprise a plurality of groups. Current control units within a same group are responsive to a change in a bit of a control value corresponding to that group to switch together between the active and inactive modes, such that the magnitude of the current is dependent on which of the groups are in the active mode. The signal timing in the associated circuit is varied in dependence on the magnitude of the current.

Timing control circuit

A timing circuit and corresponding method are provided to generate an output timing signal in dependence on an input timing signal. The timing circuit comprises a plurality of circuit components, each circuit component configured to receive an input dependent on the input timing signal and to generate an output in dependence on that input. Each circuit component performs switching operations by switching its output level in response to a transition of its input level. Each circuit component exhibits a delay in switching its output level, the delay comprising a first delay associated with a first switching of its output level and a second delay associated with a second switching of its output level. The first switching is in an opposite direction to the second switching and the first delay and the second delay exhibit a change in magnitude as each circuit component repeatedly performs its switching operations. This change in magnitude is in opposite directions for the first delay and the second delay respectively, and the plurality of circuit components are arranged such that a timing of the output timing signal is dependent on both said first delay and said second delay, such that the effects of each on the timing of the output signal counteract one another.

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Villard-Bonnot, France

Nicolaas Klarinus Johannes Van Winkelhoff