Abstract:
The disclosed embodiments relate to components of a memory system that support timing-drift calibration. In specific embodiments, this memory system contains a memory device (or multiple devices) which includes a clock distribution circuit and an oscillator circuit which can generate a frequency, wherein a change in the frequency is indicative of a timing drift of the clock distribution circuit. The memory device also includes a measurement circuit which is configured to measure the frequency of the oscillator circuit. Additionally, the memory system contains a memory controller which can transmit a request to the memory device to trigger the memory device to measure the frequency of the oscillator circuit. The memory controller is also configured to receive the measured frequency from the memory device and uses the measured frequency to determine the timing drift in the memory device.
Abstract:
The disclosed embodiments related to a clocked memory system which performs a calibration operation at a full-rate frequency to determine a full-rate calibration state that specifies a delay between a clock signal and a corresponding data signal in the clocked memory system. Next, the clocked memory system uses the full-rate calibration state to calculate a sub-rate calibration state, which is associated with a sub-rate frequency (e.g., 1/2, 1/4 or 1/8 of the full-rate frequency). The system then uses this sub-rate calibration state when the clocked memory system is operating at the sub-rate frequency. This calculation of the sub-rate state calibration states eliminates the need to perform an additional time-consuming calibration operation for each sub-rate.
Abstract:
A memory device comprising a programmable command-and-address (CA) interface and/or a programmable data interface is described. In an operational mode, two or more CA interfaces may be active. In another operational mode, at least one, but not all, CA interfaces may be active. In an operational mode, all of the data interfaces may be active. In another operational mode, at least one, but not all, data interfaces may be active. The memory device can include circuitry to select: an operational mode; a sub-mode within an operational mode; one or more CA interfaces as the active CA interface(s); a main CA interface from multiple active CA interfaces; and/or one or more data interfaces as the active data interfaces. The circuitry may perform these selection(s) based on one or more bits in one or more registers and/or one or more signals received on one or more pins.
Abstract:
The disclosed embodiments relate to components of a memory system that support timing-drift calibration. In specific embodiments, this memory system contains a memory device (or multiple devices) which includes a clock distribution circuit and an oscillator circuit which can generate a frequency, wherein a change in the frequency is indicative of a timing drift of the clock distribution circuit. The memory device also includes a measurement circuit which is configured to measure the frequency of the oscillator circuit.
Abstract:
In one embodiment, a memory device includes a memory core and input receivers to receive commands and data. The memory device also includes a register to store a value that indicates whether a subset of the input receivers are powered down in response to a control signal. A memory controller transmits commands and data to the memory device. The memory controller also transmits the value to indicate whether a subset of the input receivers of the memory device are powered down in response to the control signal. In addition, in response to a self-fresh command, the memory device defers entry into a self-refresh operation until receipt of the control signal that is received after receiving the self-refresh command.
Abstract:
In one embodiment, a memory device includes a memory core and input receivers to receive commands and data. The memory device also includes a register to store a value that indicates whether a subset of the input receivers are powered down in response to a control signal. A memory controller transmits commands and data to the memory device. The memory controller also transmits the value to indicate whether a subset of the input receivers of the memory device are powered down in response to the control signal. In addition, in response to a self-fresh command, the memory device defers entry into a self-refresh operation until receipt of the control signal that is received after receiving the self-refresh command.
Abstract:
In one embodiment, a memory device includes a memory core and input receivers to receive commands and data. The memory device also includes a register to store a value that indicates whether a subset of the input receivers are powered down in response to a control signal. A memory controller transmits commands and data to the memory device. The memory controller also transmits the value to indicate whether a subset of the input receivers of the memory device are powered down in response to the control signal. In addition, in response to a self-fresh command, the memory device defers entry into a self-refresh operation until receipt of the control signal that is received after receiving the self-refresh command.
Abstract:
In one embodiment, a memory device includes a memory core and input receivers to receive commands and data. The memory device also includes a register to store a value that indicates whether a subset of the input receivers are powered down in response to a control signal. A memory controller transmits commands and data to the memory device. The memory controller also transmits the value to indicate whether a subset of the input receivers of the memory device are powered down in response to the control signal. In addition, in response to a self-fresh command, the memory device defers entry into a self-refresh operation until receipt of the control signal that is received after receiving the self-refresh command.
Abstract:
In a multirank memory system in which the clock distribution trees of each rank are permitted to drift over a wide range (e.g., low power memory systems), the fine-interleaving of commands between ranks is facilitated through the use of techniques that cause each addressed rank to properly sample commands intended for that rank, notwithstanding the drift. The ability to perform such “microthreading” provides for substantially enhanced memory capacity without sacrificing the performance of single rank systems. This disclosure provides methods, memory controllers, memory devices and system designs adapted to these ends.
Abstract:
In one embodiment, a memory device includes a memory core and input receivers to receive commands and data. The memory device also includes a register to store a value that indicates whether a subset of the input receivers are powered down in response to a control signal. A memory controller transmits commands and data to the memory device. The memory controller also transmits the value to indicate whether a subset of the input receivers of the memory device are powered down in response to the control signal. In addition, in response to a self-fresh command, the memory device defers entry into a self-refresh operation until receipt of the control signal that is received after receiving the self-refresh command.