Abstract: The present invention discloses a neural network accelerator and a neural network acceleration method based on structured pruning and low-bit quantization. The neural network accelerator includes a master controller, an activations selection unit, an extensible calculation array, a multifunctional processing element, a DMA, a DRAM and a buffer. The present invention makes full use of the data reusability during inference operation of a neural network, reduces the power consumption of selecting input activation and weights of effective calculations, and relieves the high transmission bandwidth pressure between the activations selection unit and the extensible calculation array through structured pruning and data sharing on the extensible calculation array, reduces the number of weight parameters and the storage bit width by combining the low-bit quantization technology, and further improves the throughput rate and energy efficiency of the convolutional neural network accelerator.

Abstract: The present disclosure provides a multiplication and accumulation circuit based on radix-4 booth code and differential weight storage. The circuit includes an input data encoding circuit, a differential weight storage circuit, an integral calculation circuit and a differential ADC circuit. The input data encoding circuit is configured to encode original input data. The differential weight storage circuit is configured to store weight values, and multiply the original input data after being encoded by the weight values stored to obtain multiplication results. The integral calculation circuit is configured to respectively accumulate a positive value and a negative value of each multiplication result. The differential ADC circuit is configured to perform analog-to-digital conversion on a difference between accumulated results of the positive values and the negative values to obtain a digital multiplication and accumulation result.

Abstract: According to various embodiments, a write control circuit configured to control writing to a memory cell by applying a writing current to the memory cell may be provided. The write control circuit may include: a current application circuit configured to apply the writing current to the memory cell; a determination circuit configured to determine whether writing to the memory cell is finished; and a stop writing circuit configured to cut off the writing current from the memory cell if it is determined that writing to the memory cell is finished.

Abstract: A method of writing a first state or a second state to a memory cell may be provided. Writing the first state to the memory cell may include electrically connecting a first switch in electrical connection to a first end of the memory cell to a first voltage and electrically connecting a second switch in electrical connection to a second end of the memory cell to a fourth voltage to apply a first potential difference to cause formation of the first state in the memory cell. Writing the second state to the memory cell may include electrically connecting the first switch to the second voltage and electrically connecting the second switch to the third voltage to apply a second potential difference to cause formation of the second state in the memory cell.

Abstract: A reading circuit for a resistive memory cell is provided, the circuit including a current source, a precharge switch, a comparator circuit including a first input node (in-node), and a second in-node, the precharge switch configured to couple the current source to the first in-node to apply a precharge voltage during a first reading time period, and to decouple the current source during a second reading time period, the comparator circuit configured to operate during a third reading time period, a memory cell access switch to enable a current flow at least partially during the second and the third reading time periods through a memory cell, the comparator circuit configured to compare a voltage at the first in-node with a reference voltage at the second in-node and to determine a programming state of the memory cell based on the voltage at the first in-node during the third reading time period.

Abstract: According to various embodiments, a write control circuit configured to control writing to a memory cell by applying a writing current to the memory cell may be provided. The write control circuit may include: a current application circuit configured to apply the writing current to the memory cell; a determination circuit configured to determine whether writing to the memory cell is finished; and a stop writing circuit configured to cut off the writing current from the memory cell if it is determined that writing to the memory cell is finished.

Abstract: A writing circuit for a magnetoresistive memory cell is provided.

Abstract: A latch circuit is described comprising a switchable resistive element and a switching circuit configured to set the switchable resistive element to a first resistive state in response to receiving a set signal and to set the switchable resistive element to a second resistive state in response to receiving a reset signal.

Abstract: A method of writing a first state or a second state to a memory cell may be provided. Writing the first state to the memory cell may include electrically connecting a first switch in electrical connection to a first end of the memory cell to a first voltage and electrically connecting a second switch in electrical connection to a second end of the memory cell to a fourth voltage to apply a first potential difference to cause formation of the first state in the memory cell. Writing the second state to the memory cell may include electrically connecting the first switch to the second voltage and electrically connecting the second switch to the third voltage to apply a second potential difference to cause formation of the second state in the memory cell.

Abstract: A writing circuit for a magnetoresistive memory cell is provided.

Abstract: A reading circuit for a resistive memory cell is provided, the circuit including a current source, a precharge switch, a comparator circuit including a first input node (in-node), and a second in-node, the precharge switch configured to couple the current source to the first in-node to apply a precharge voltage during a first reading time period, and to decouple the current source during a second reading time period, the comparator circuit configured to operate during a third reading time period, a memory cell access switch to enable a current flow at least partially during the second and the third reading time periods through a memory cell, the comparator circuit configured to compare a voltage at the first in-node with a reference voltage at the second in-node and to determine a programming state of the memory cell based on the voltage at the first in-node during the third reading time period.

Abstract: A current writing circuit for a resistive memory cell arrangement is provided. The current writing circuit comprises a first current source; a first reference potential terminal; a first switch configured to switch between the first current source and the first reference potential terminal during a write operation; a second current source; a second reference potential terminal; and a second switch configured to switch between the second reference potential terminal when the first switch is switched to the first current source, and the second current source when the first switch is switched to the first reference potential terminal, during the write operation, wherein the first current source and the second current source are of the same polarity. Further embodiments relate to a memory cell arrangement and a method of writing into a target resistive memory cell of a resistive memory cell arrangement.

Abstract: A current writing circuit for a resistive memory cell arrangement is provided. The current writing circuit comprises a first current source; a first reference potential terminal; a first switch configured to switch between the first current source and the first reference potential terminal during a write operation; a second current source; a second reference potential terminal; and a second switch configured to switch between the second reference potential terminal when the first switch is switched to the first current source, and the second current source when the first switch is switched to the first reference potential terminal, during the write operation, wherein the first current source and the second current source are of the same polarity. Further embodiments relate to a memory cell arrangement and a method of writing into a target resistive memory cell of a resistive memory cell arrangement.