Abstract:
In some examples, a memory device has a memory array configured to include sets of bit cells grouped based in part on an arrangement of local source lines. Each of the groups of cells may include an assist bit having a lower impedance than the other bit cells of the group to cause current distributed by the local source lines to be largely provided to the assist bit. In some examples, the assist bit include a shorted tunnel junction and in other examples, multiple assist bits may be connected by one or more bridge assisted bit lines.
Abstract:
A method of reading data from a plurality of bits in a spin-torque magnetoresistive memory array includes performing one or more referenced read operations of the bits, and performing a self-referenced read operation, for example, a destructive self-referenced read operation, of any of the bits not successfully read by the referenced read operation. The referenced read operations can be initiated at the same time or prior to that of the destructive self-referenced read operation.
Abstract:
Circuitry and a method for regulating voltages applied to magnetoresistive bit cells of a spin-torque magnetoresistive random access memory (ST-MRAM) reduces time-dependent dielectric breakdown stress of the word line transistors. During a read or write operation, only the ends of the selected bit cells are pulled down to a low voltage and/or pulled up to a high voltage depending on the operation (write 0, write 1, and read) being performed. The ends of the unselected bit cells are held at a precharge voltage while separately timed signals pull up or pull down the ends of the selected bit cells during read and write operations.
Abstract:
A cell bias control circuit maximizes the performance of devices in the read/write path of memory cells (magnetic tunnel junction device+transistor) without exceeding leakage current or reliability limits by automatically adjusting multiple control inputs of the read/write path at the memory array according to predefined profiles over supply voltage, temperature, and process corner variations by applying any specific reference parameter profiles to the memory array.
Abstract:
A method of reading data from a plurality of bits in a spin-torque magnetoresistive memory array includes performing one or more referenced read operations of the bits, and performing a self-referenced read operation, for example, a destructive self-referenced read operation, of any of the bits not successfully read by the referenced read operation. The referenced read operations can be initiated at the same time or prior to that of the destructive self-referenced read operation.
Abstract:
In a spin-torque magnetic random access memory (MRAM) that includes local source lines, auto-booting of the word line is used to conserve power consumption by reusing charge already present from driving a plurality of bit lines during writing operations. Auto-booting is accomplished by first driving the word line to a first word line voltage. After such driving, the word line isolated. Subsequent driving of the plurality of bit lines that are capacitively coupled to the word line causes the word line voltage to be increased to a level desired to allow sufficient current to flow through a selected memory cell to write information into the selected memory cell. Additional embodiments include the use of a supplemental voltage provider that is able to further boost or hold the isolated word line at the needed voltage level.
Abstract:
In some examples, a memory device is configured to receive a precharge command and an activate command. The memory device performs a first series of events related to the precharge command in response to receiving the precharge command and a second series of events related to the activate command in response to receiving the activate command. The memory device delays the start of the second series of events until the first series of events completes.
Abstract:
In some examples, a memory device is configured to receive a precharge command and an activate command. The memory device performs a first series of events related to the precharge command in response to receiving the precharge command and a second series of events related to the activate command in response to receiving the activate command. The memory device delays the start of the second series of events until the first series of events completes.
Abstract:
In some examples, a memory device is configured with non-volatile memory array(s) having one or more associated volatile memory arrays. The memory device may include a non-destructive write mode configured to prevent access to the non-volatile memory array(s) during an initiation or calibration sequence performed by the memory device or an electronic device associated with the memory device to calibrate read and write access timing associated with the memory device.
Abstract:
In some examples, a memory device includes multiple memory banks equipped with an isolation switch and dedicated power supply pins. The isolation switch of each memory bank is configured to isolate the memory bank from global signals. The dedicated power supply pins are configured to connect each of the memory banks to a dedicated local power supply pads on the package substrate to provide local dedicated power supplies to each of the memory banks and to reduce voltage transfer between memory banks over conductors on the device, the device substrate, or the package substrate of the memory device.