Micron Technology Incorporated

Round Rock Research, LLC

Joo S Choi

Troy A Manning

Brent Keeth

James Brian Johnson

Brian L Johnson

David K Ovard

George Edward Pax

Roy Edgar Greeff

Ronnie M Harrison

Dragos Dimitriu

Yogesh Sharma

Greg King

A technique to increase transfer rate of command and address signals via a given number of command and address pins in each of one or more integrated circuit memory devices during a clock cycle of a clock signal. In one example embodiment, the command and address signals are sent on both rising and falling edges of a clock cycle of a clock signal to increase the transfer rate and essentially reduce the number of required command and address pins in each integrated circuit memory device.

Memory command received within two clock cycles

Dual event command

A system having a processor, a memory controller coupled to said processor, a plurality of dynamic random access memory (DRAM) chips coupled to said memory controller and at least one of said DRAM chips comprising a clock synchronization circuit to receive a reference clock signal and to output a synchronized clock output signal. The system has a plurality of signal buses coupling the processor to the memory controller and the memory controller to said DRAM chips. The signal line conveys signals from said memory controller to said clock synchronization circuit to turn on and off the clock synchronization circuit according to control logic. A memory READ command triggered clock synchronization mode turns on a clock synchronization circuit only for memory READ operations. The clock synchronization circuit achieves a signal lock with the reference clock signal in less time than the column address strobe latency. Precise memory READ operations are thus possible without wasting power when such operations are not performed by allowing the clock synchronization circuitry to be turned off.

Read command triggered synchronization circuitry

A signal capture system and method is used to capture a data signal using a data strobe signal having a preamble of strobe signal transitions. The system includes a data latch circuit receiving the data signal. The data latch circuit is clocked by transitions of the data strobe signal to capture respective bits of data corresponding to the data signal. A decoder receives a memory command signal and generates a data start signal after a delay period from receiving the memory command signal if the command signal corresponds to a read or a write command. The receipt of read or write command signals is used by a control circuit to identify the start of valid read or write data signals. The control circuit then outputs the captured data signals responsive to the data start signal, thereby ignoring the transitions in the preamble of the data strobe signal.

System and method for capturing data signals using a data strobe signal

A memory READ command triggered clock synchronization mode turns on a clock synchronization circuit only for memory READ operations. The clock synchronization circuit achieves a signal lock with the reference clock signal in less time than the column address strobe latency. Precise memory READ operations are thus possible without wasting power when such operations are not performed by allowing the clock synchronization circuitry to be turned off.

A memory device has data transceivers, write strobe transceivers, and read strobe transceivers. The data transceivers transfer input data to the memory device and transfer output data from the memory device. The write strobe transceivers transfer timing information of the input data. The read strobe transceivers transfer timing information of the output data. The memory device also has an auxiliary circuit for generating auxiliary information. The auxiliary information includes information different from the timing information of the input data and the output data. The auxiliary circuit uses the write and read transceivers to transfer the auxiliary information to and from the memory device.

Memory device having strobe terminals with multiple functions

A memory device includes terminals for transferring input data and output data to and from a memory array. The memory device also includes an auxiliary circuit for receiving input auxiliary information associated with the input data and for generating output auxiliary information associated with the output data. The input and output auxiliary information include inverting codes, parity codes, temperature information and time delay information. The input and output auxiliary information are transferred to and from the memory device on the same terminals that the input data and the output data are transferred.

Memory device having terminals for transferring multiple types of data

A method and system for generating a reference voltage for memory device signal receivers operates in either a calibration mode or a normal operating mode. In the calibration mode, the magnitude of the reference voltage is incrementally varied, and a digital signal pattern is coupled to the receiver at each reference voltage. An output of the receiver is analyzed to determine if the receiver can accurately pass the signal pattern at each reference voltage level. A range of reference voltages that allow the receiver to accurately pass the signal pattern is recorded, and a final reference voltage is calculated at the approximate midpoint of the range. This final reference voltage is applied to the receiver during normal operation.

Growing community of inventors

Boise, ID, United States of America

Joo S Choi