Static information storage and retrieval – Read/write circuit – Testing
Patent
1990-08-17
1992-07-28
Popek, Joseph A.
Static information storage and retrieval
Read/write circuit
Testing
36518903, G11C 2900
Patent
active
051345862
ABSTRACT:
An integrated circuit having a normal operating mode and a special operating mode, such as a special test mode, is disclosed. The special test mode is enabled by a series of signals, such as overvoltage excursions at a terminal, rather than by a single such excursion, so that it is less likely that the special test mode is entered inadvertently, such as due to noise or power-down and power-up of the device. The circuit for enabling the test mode includes a series of D-type flip-flops, each of which are clocked upon detection of the overvoltage condition together with a particular logic level applied at another terminal; multiple series of flip-flops may be provided for multiple special test modes. Additional features include the provision of a power-on reset circuit which locks out the entry into the test mode during power-up of the device. Acknowledgment of the entry into test mode is provided by the presentation of a low impedance at output terminals while the device is not enabled; chip enable of the device causes the device to exit the test mode. Once in test mode, the output enable terminal of the device can provide a chip enable function.
REFERENCES:
patent: 4654849 (1987-03-01), White, Jr. et al.
patent: 4860259 (1989-08-01), Tobita
patent: 4879689 (1989-11-01), Atsumi et al.
McAdams et al., "A 1-Mbit CMOS Dynamic RAM with Design--For Test Functions", IEEE Journal of Solid-State Circuits (Oct. 1986), vol. SC-21, No. 5, pp. 635-642.
Shimada et al., "A 46-ns 1-Mbit CMOS SRAM", IEEE Journal of Solid-State Circuits (Feb. 1988), vol. 23, No. 1, pp. 53-58.
Anderson Rodney M.
Jorgenson Lisa K.
Popek Joseph A.
Robinson Richard K.
SGS-Thomson Microelectronics Inc.
LandOfFree
Semiconductor memory with chip enable control from output enable does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Semiconductor memory with chip enable control from output enable, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiconductor memory with chip enable control from output enable will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1691466