Electrical computers and digital processing systems: memory – Storage accessing and control
Reexamination Certificate
2000-06-01
2001-11-20
Yoo, Do Hyun (Department: 2187)
Electrical computers and digital processing systems: memory
Storage accessing and control
C711S219000, C714S719000
Reexamination Certificate
active
06321291
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to techniques for measuring the speed of memory unit in an integrated circuit (IC), and more specifically to a built-in hardware arrangement for measuring a time interval between two consecutive outputs of the memory unit.
2. Description of the Related Art
As is known in the art, it is very important to precisely determine the speed of memory unit that is provided in an IC. A useful measure of the speed of memory unit is the time that elapses between the initiation of an operation and the completion of that operation. This is referred to as the memory access time. Another important measure is the memory cycle time, which is the minimum time delay required between the initiation of two successive memory operations.
One known technique of measuring the speed of IC memory is to successively apply memory addresses from external and detect each memory output. An IC tester is used to measure the time delay between the application of each address and the detection of the data derived from the memory. As is known, a buffer amplifier is provided between the memory and the output pins. This buffer amplifier unit inherently provides a relatively large amount of delay before the data is derived from the memory unit via the IC output pins. Thus, with the above mentioned method, it is very difficult to accurately measure the speed of memory unit.
Another approach to measuring the memory speed is to provide a memory speed measuring unit within an IC memory itself. One example of such techniques is disclosed in Japanese Laid-open Patent Application No. 4-274100. According to this conventional technique, a plurality of delay elements are incorporated in an IC memory module to determine a memory access time. However, this technique detects a memory access time at a time interval which is determined by the delay elements and accordingly, it is not expected to precisely determine the speed of memory unit.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a hardware arrangement that is built in a memory module and is able to accurately measure the speed of memory.
Another object of the present invention is to provide a method of accurately measuring the speed of memory using a built-in measuring hardware. In brief, these objects are achieved by a technique wherein in order to precisely measure the speed of memory unit, the memory unit stores at least one bit data at a predetermined bit position at each memory word. That is, the logical value of the one bit data changes alternately in order of memory address. An address increment circuit, which is provided in a module including the memory unit, successively generates memory addresses which are applied to the memory. The address increment circuit increments a memory address in response to the output of the memory. The memory speed between two consecutive memory outputs is detected by measuring a pulse width of a pulse signal outputted from the memory unit. Thus, a relatively large delay otherwise caused at a buffer amplifier can effectively be compensated.
REFERENCES:
patent: 3805152 (1974-04-01), Ebersman et al.
patent: 4949242 (1990-08-01), Takeuchi et al.
patent: 5018145 (1991-05-01), Kikuchi et al.
patent: 5636225 (1997-06-01), Osawa
patent: 5704035 (1997-12-01), Shipman
patent: 5892776 (1999-04-01), Kumakura
patent: 5910181 (1999-06-01), Hatakenaka et al.
patent: 48-26036 (1973-04-01), None
patent: 62-120698 (1987-06-01), None
patent: 64-25400 (1989-01-01), None
patent: 3-30200 (1991-02-01), None
patent: 4-274100 (1992-09-01), None
patent: 9-91995 (1997-04-01), None
Moazzami Nasser
NEC Corporation
Scully Scott Murphy & Presser
Yoo Do Hyun
LandOfFree
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