Stmicroelectronics International N.v.

Stmicroelectronics S.r.l.

Stmicroelectronics Pvt. Ltd.

Stmicroelectronics S.a.

Nitin Chawla

Manuj Ayodhyawasi

Promod Kumar

Kedar Janardan Dhori

Anuj Grover

Harsh Rawat

Giuseppe Desoli

Thomas Boesch

Surinder Pal Singh

Tanmoy Roy

Kallol Chatterjee

Chittoor Parthasarathy

Tanuj Kumar

Bhupender Singh

Hitesh Chawla

Pascal Urard

Rakesh Malik

Aditya Bhuvanagiri

Elio Guidetti

Fabio Giuseppe De Ambroggi

Paolo Zambotti

Harvinder Singh

Tommaso Majo

Aditha Bhuvanagiri

Halvinder Singh

An in-memory computation circuit includes a memory array with SRAM cells connected in rows by word lines and in columns by bit lines. A row controller circuit simultaneously actuates word lines in parallel for an in-memory compute operation. A column processing circuit includes a read circuit that operates to reduce sensitivity to variation in bit line read current. Additionally, a testing circuit senses analog signals on the complementary bit lines to identify one of the complementary bit lines as having a less variable read current. That identified one of the complementary bit lines is coupled to the read circuit for the in-memory compute operation.

Enhanced accuracy of bit line reading for an in-memory compute operation by accounting for variation in read current

An in-memory computation circuit includes a memory array with SRAM cells connected in rows by word lines and in columns by bit lines. A row controller circuit simultaneously actuates word lines in parallel for an in-memory compute operation. A column processing circuit includes a current mirroring circuit that mirrors the read current developed on each bit line in response to the simultaneous actuation to generate a decision output for the in-memory compute operation. A bias voltage for word line driver and a configuration of the current mirroring circuit to inhibit drop of a voltage on the bit line below a bit flip voltage during execution of the in-memory compute operation. The mirrored read current is integrated by an integration capacitor to generate an output voltage that is converted to a digital signal by an analog-to-digital converter circuit.

Bit line read current mirroring circuit for an in-memory compute operation where simultaneous access is made to plural rows of a static random access memory (SRAM)

A memory circuit includes an address port, a data input port and a data output port. An upstream shadow logic circuit is coupled to provide address data to the address port of the memory circuit and input data to the data input port of the memory circuit. A downstream shadow logic circuit is coupled to receive output data from the data output port of the memory circuit. The memory circuit includes a bypass path between the address port and the data output port. This bypass path is activated during a testing operation to pass bits of the address data (forming test data) applied by upstream shadow logic circuit from the address port to the data output port.

At-speed transition fault testing for a multi-port and multi-clock memory

An in-memory computation circuit includes a memory array including sub-arrays of with SRAM cells connected in rows by word lines and in columns by local bit lines. A row controller circuit selectively actuates one word line per sub-array for an in-memory compute operation. A global bit line is capacitively coupled to many local bit lines in either a column direction or row direction. An analog global output voltage on each global bit line is an average of local bit line voltages on the capacitively coupled local bit lines. The analog global output voltage is sampled and converted by an analog-to-digital converter (ADC) circuit to generate a digital decision signal output for the in-memory compute operation.

In-memory computation circuit using static random access memory (SRAM) array segmentation

A memory array arranged as a plurality of memory cells. The memory cells are configured to operate at a determined voltage. A memory management circuitry coupled to the plurality of memory cells tags a first set of the plurality of memory cells as low-voltage cells and tags a second set of the plurality of memory cells as high-voltage cells. A power source provides a low voltage to the first set of memory cells and provides a high voltage to the second set of memory cells based on the tags.

Tagged memory operated at lower VMIN in error tolerant system

The memory array of a circuit includes sub-arrays with memory cells arranged in a row-column matrix where each row includes a word line and each sub-array column includes a local bit line. A control circuit supports two modes of circuit operation: a first mode where only one word line in the memory array is actuated during a memory read and a second mode where one word line per sub-array are simultaneously actuated during the memory read. An input/output circuit for each column includes inputs to the local bit lines of the sub-arrays, a column data output coupled to the bit line inputs, and a sub-array data output coupled to each bit line input. In memory computation operations are performed in the second mode as a function of feature data and weight data stored in the memory.

Memory architecture supporting both conventional memory access mode and digital in-memory computation processing mode

An in-memory computation circuit includes a memory array with SRAM cells connected in rows by word lines and in columns by bit lines. Each row includes a word line drive circuit powered by an adaptive supply voltage. A row controller circuit simultaneously actuates word lines in parallel for an in-memory compute operation. A column processing circuit processes analog voltages developed on the bit lines in response to the simultaneous actuation to generate a decision output for the in-memory compute operation. A voltage generator circuit generates the adaptive supply voltage for powering the word line drive circuits during the simultaneous actuation. A level of the adaptive supply voltage is modulated dependent on integrated circuit process and/or temperature conditions in order to optimize word line underdrive performance and inhibit unwanted memory cell data flip.

Adaptive word line underdrive control for an in-memory compute operation where simultaneous access is made to plural rows of a static random access memory (SRAM)

A memory circuit includes an array of memory cells arranged in rows and columns. A word line is connected to the memory cells of each row. A row decoder circuit operates in response to an internal clock and an address to selectively apply a word line signal to one word line and further generate a dummy word line signal. A control circuit includes a clock generator that generates the internal clock which is reset in response to a reset signal. A first delay circuit receives the dummy word line signal and outputs a first delayed dummy word line signal. A second delay circuit receives the dummy word line signal and outputs a second delayed dummy word line signal. A multiplexer circuit selects between the first and second delayed dummy word line signals for output as the reset signal in response to a logic state of a mode control signal.

Tuning of read/write cycle time delay for a memory circuit dependent on operational mode selection

Systems and devices are provided to enable granular control over a retention or active state of each of a plurality of memory circuits, such as a plurality of memory cell arrays, within a memory. Each respective memory array of the plurality of memory arrays is coupled to a respective ballast driver and a respective active memory signal switch for the respective memory array. One or more voltage regulators are coupled to a ballast driver gate node and to a bias node of at least one of the respective memory arrays. In operation, the respective active memory signal switch for a respective memory array causes the respective memory array to transition between an active state for the respective memory array and a retention state for the respective memory array.

Computing system power management device, system and method

An in-memory compute (IMC) device includes an array of memory cells and control logic coupled to the array of memory cells. The array of memory cells is arranged as a plurality of rows of cells intersecting a plurality of columns of cells. The array of memory cells includes a first subset of memory cells forming a plurality of computational engines at intersections of rows and columns of the first subset of the array of memory cells. The array also includes a second subset of memory cells forming a plurality of bias engines. The control logic, in operation, generates control signals to control the array of memory cells to perform a plurality of IMC operations using the computational engines, store results of the plurality of IMC operations in memory cells of the array, and computationally combine results of the plurality of IMC operations with respective bias values using the bias engines.

In-memory compute array with integrated bias elements

A circuit includes a memory array with SRAM cells connected in rows by word lines and in columns by bit lines. A row controller circuit simultaneously actuates, through a word line driver circuit for each row, word lines in parallel for an in-memory compute operation. A column processing circuit processes analog voltages developed on the bit lines in response to the simultaneous actuation to generate a decision output for the in-memory compute operation. A bit line clamping circuit includes a sensing circuit that compares the analog voltages on a given pair of bit lines to a threshold voltage. A voltage clamp circuit is actuated in response to the comparison to preclude the analog voltages on the given pair of bit lines from decreasing below a clamping voltage level.

Selective bit line clamping control for an in-memory compute operation where simultaneous access is made to plural rows of a static random access memory (SRAM)

A memory array includes a plurality of bit-cells arranged as a set of rows of bit-cells intersecting a plurality of columns. The memory array also includes a plurality of in-memory-compute (IMC) cells arranged as a set of rows of IMC cells intersecting the plurality of columns of the memory array. Each of the IMC cells of the memory array includes a first bit-cell having a latch, a write-bit line and a complementary write-bit line, and a second bit-cell having a latch, a write-bit line and a complementary write-bit line, wherein the write-bit line of the first bit-cell is coupled to the complementary write-bit line of the second bit-cell and the complementary write-bit line of the first bit-cell is coupled to the write-bit line of the second bit-cell.

Bit-cell architecture based in-memory compute

An in-memory computation circuit includes a memory array with SRAM cells connected in rows by word lines and in columns by bit lines. Body bias nodes of the transistors in each SRAM cell are biased by a modulated body bias voltage. A row controller circuit simultaneously actuates word lines in parallel for an in-memory compute operation. A column processing circuit processes analog voltages developed on the bit lines in response to the simultaneous actuation to generate a decision output for the in-memory compute operation. A voltage generator circuit switches the modulated body bias voltage from a non-negative voltage level to a negative voltage level during the simultaneous actuation. The negative voltage level is adjusted dependent on integrated circuit process and/or temperature conditions in order to optimize protection against unwanted memory cell data flip.

Adaptive body bias management for an in-memory compute operation where simultaneous access is made to plural rows of a static random access memory (SRAM)

The memory array of a memory includes sub-arrays with memory cells arranged in a row-column matrix where each row includes a word line and each sub-array column includes a local bit line. A row decoder circuit supports two modes of memory circuit operation: a first mode where only one word line in the memory array is actuated during a memory read and a second mode where one word line per sub-array are simultaneously actuated during the memory read. An input/output circuit for each column includes inputs to the local bit lines of the sub-arrays, a column data output coupled to the bit line inputs, and a sub-array data output coupled to each bit line input. Both BIST and ATPG testing of the input/output circuit are supported. For BIST testing, multiple data paths between the bit line inputs and the column data output are selectively controlled to provide complete circuit testing.

Built-in self test circuit for segmented static random access memory (SRAM) array input/output

Embodiments are directed towards a system on chip (SoC) that implements a deep convolutional network heterogeneous architecture. The SoC includes a system bus, a plurality of addressable memory arrays coupled to the system bus, at least one applications processor core coupled to the system bus, and a configurable accelerator framework coupled to the system bus. The configurable accelerator framework is an image and deep convolutional neural network (DCNN) co-processing system. The SoC also includes a plurality of digital signal processors (DSPs) coupled to the system bus, wherein the plurality of DSPs coordinate functionality with the configurable accelerator framework to execute the DCNN.

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Noida, India

Nitin Chawla