Sperry Rand Corporation

Merton A Horne

Bruce A Brillhart

Walter W Heikkila

Thomas A Pogemiller

A sense amplifier/latch circuit for a Metal Nitride Oxide (MNOS) Block Orgaized Random Access Memory (BORAM) with analog memory retention interrogation capabilities. The sense amplifier/latch circuit includes the associative memory transistors as an integral part of the latch as well as circuitry for increasing the switching speed of the sense latch in response to the differing conductances of the memory transistors when a row address voltage is applied to their gates.

MNOS BORAM sense amplifier/latch

An improved sense latch circuit for differentially sensing an MNOS memory FET's voltage thresholds, selectively operable in either a memory retention or read interrogation mode with enhanced sensitivity and improved power conservation. The improvement consisting of the additional cross coupling of each of the latch outputs to a respective plurality of MOS FETs coupled in series with each of the MNOS FET inputs, which cross coupling reduces extraneous current paths and increases the switching sensitivity of the sense latch circuit.

MNOS FET memory retention characterization test circuit with enhanced

A method and sense latch circuit are described for determining the memory retention characteristics of differentially sensed metal nitride oxide semiconductor field effect transistor (MNOS FET) memory cells and arrays made up of such cells. The method involves substitution of one differential comparator input with a known reference voltage (VR) for determining the analog voltage threshold levels of the memory cells. The sense latch circuit, which can be fabricated as an integrated circuit, is responsively coupled to control inputs so that it can be operated in either a read or memory retention interrogation mode. The determination of the analog threshold levels of each cell of an array at given times permits the determination of the array's memory window (i.e., memory retention characteristics).

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Eagan, MN, United States of America

Merton A Horne