An array of memory cells can be configured into one or more scan chains that uses non-overlapping scan word line pulses in a direction opposite to a direction of the scan chain to shift scan bits in the direction of the scan chain from a scan chain input to a scan chain output. A memory cell may include a latch and a scan input multiplexer. The array includes a pulse generator to derive a pulse generator output from a clock pulse, and a digital delay line to generate the non-overlapping scan word line pulses from the pulse generator output. The scan chain may include a latch from an input buffer and may scan multiple columns or rows.

A method is disclosed for scanning an array of memory cells arranged in rows and columns, where the array includes a scan chain partitioned into multiple sections. Each section includes a first scan multiplexer, a section buffer cell, and multiple memory cells. The method includes determining whether a scan shift mode is entered, asserting a scan enable signal to select second inputs of each first scan multiplexer when the scan shift mode is entered, coupling the scan input with the input of the section buffer cell of the first section, and coupling the output of the memory cell in the previous section with the input of the section buffer cell in the next section. The method further includes updating the contents of the section buffer cell and the memory cells using clock signals and scan word line pulses.

A method is disclosed for scanning an array of memory cells arranged in rows and columns, where the array includes a scan chain partitioned into multiple sections. Each section includes a first scan multiplexer, a section buffer cell, and multiple memory cells. The method includes determining whether a scan shift mode is entered, asserting a scan enable signal to select second inputs of each first scan multiplexer when the scan shift mode is entered, coupling the scan input with the input of the section buffer cell of the first section, and coupling the output of the memory cell in the previous section with the input of the section buffer cell in the next section. The method further includes updating the contents of the section buffer cell and the memory cells using clock signals and scan word line pulses.

Apparatuses and techniques for logging a memory address associated with faulty usage-based disturbance data are described. In an example aspect, a memory device can detect, at a local-bank level, a fault associated with usage-based disturbance data. This detection enables the memory device to log a row address associated with the faulty usage-based disturbance data. To avoid increasing a complexity and/or a size of the memory device, some implementations of the memory device can perform the address logging at the multi-bank level with the assistance of an engine, such as a test engine. The memory device stores the logged address in at least one mode register to communicate the fault to a memory controller. With the logged address, the memory controller can initiate a repair procedure to fix the faulty usage-based disturbance data.

Apparatuses and techniques for logging a memory address associated with faulty usage-based disturbance data are described. In an example aspect, a memory device can detect, at a local-bank level, a fault associated with usage-based disturbance data. This detection enables the memory device to log a row address associated with the faulty usage-based disturbance data. To avoid increasing a complexity and/or a size of the memory device, some implementations of the memory device can perform the address logging at the multi-bank level with the assistance of an engine, such as a test engine. The memory device stores the logged address in at least one mode register to communicate the fault to a memory controller. With the logged address, the memory controller can initiate a repair procedure to fix the faulty usage-based disturbance data.

A memory-testing circuit in a circuit comprises: a test controller; a memory data source selection device configured to select input data for a write port of the memory from test data outputted from the test controller and data from an output of the memory; and a memory address source selection device configured to select an address for an address port of the memory from an address outputted from the test controller and one of one or more preset addresses of the memory. The one or more preset addresses correspond to one or more preserved locations of the memory configured to temporarily store data for one or more locations of the memory to be tested.

A memory-testing circuit in a circuit comprises: a test controller; a memory data source selection device configured to select input data for a write port of the memory from test data outputted from the test controller and data from an output of the memory; and a memory address source selection device configured to select an address for an address port of the memory from an address outputted from the test controller and one of one or more preset addresses of the memory. The one or more preset addresses correspond to one or more preserved locations of the memory configured to temporarily store data for one or more locations of the memory to be tested.

An apparatus and method for performing memory operations in memory stacks comprising receiving a memory operation request at a first memory controller, where the first memory controller is in included in a first logic die in communication with a first memory die of a first memory technology, from a processor via a first bus. The method further comprising, on a condition that the memory operation request is associated with a second memory technology, communicating the memory operation request to a second memory controller via a side bus, where the second memory controller is included in a second logic die in communication with a second memory die of the second memory technology, and, on a condition that the memory operation request is associated with the first memory technology, performing the memory operation request. The first and second logic dies and the first and second memory dies being stacked on the processor.

An apparatus and method for performing memory operations in memory stacks comprising receiving a memory operation request at a first memory controller, where the first memory controller is in included in a first logic die in communication with a first memory die of a first memory technology, from a processor via a first bus. The method further comprising, on a condition that the memory operation request is associated with a second memory technology, communicating the memory operation request to a second memory controller via a side bus, where the second memory controller is included in a second logic die in communication with a second memory die of the second memory technology, and, on a condition that the memory operation request is associated with the first memory technology, performing the memory operation request. The first and second logic dies and the first and second memory dies being stacked on the processor.

An apparatus includes one or more control circuit configured to connect to a nonvolatile memory cell structure that includes nonvolatile memory cells each having a programmable resistive element. The one or more control circuit is configured to receive an address that corresponds to a location in the nonvolatile memory cell structure and set a variable resistor according to the location. The variable resistor is connected in series with a selected nonvolatile memory cell that is located at the location. The one or more control circuit is further configured to drive a memory access current through the selected nonvolatile memory cell and the variable resistor in series.