International Business Machines Corporation

Friedrich C Wernicke

Wilfried Klein

Erich Klink

Dieter F Wendel

Knut K Najmann

Helmut H Heimeier

Rudolf Brosch

Jurgen Pille

Manoj N Kumar

Robert C Wong

George McNeil Lattimore

Joachim Keinert

Siegfried K Wiedmann

Michael Kevin Ciraula

Ronald W Knepper

Volker Rudolph

Klaus Heuber

Stefan Buettner

Joseph M Poplawski, Jr

William B Chin

Rudolph D Dussault

Wielfried Klein

Stefan Buttner

A new method is indicated for the restore of bitlines and data-lines from memory-cells. All bit- and datalines are switched together during the restore activity so that all restore-FETs can be prepared with the necessary re-charging current. The non-addressed bitlines are then switched off through their bitswitches. In this manner, the dimensions of the re-charging devices can be considerably reduced.

Restore function for memory cells using negative bitline-selection

Static wordline redundancy memory device

A method and apparatus for providing single clock cycle pipelined access of a memory system, which combines synchronization and self resetting techniques, includes an array of memory cells that are arranged into columns and rows and intercoupled by bit lines and word lines. The memory system also includes an address decoder and a sense enable circuit. The address decoder, upon receiving an address, interprets the address to enable a particular word line, or word lines, and to disable precharging of a bit line, or bit lines. With the word line active, the sense enable circuit generates a sense enable signal when the clock signal has encountered a transitional edge, or is in an active state. When the sense enable signal is active, the sense amplifier reads the data from the addressed memory cell via the bit lines to produce output data.

Method and apparatus for synchronized pipeline data access of a memory

A transistor memory cell is disclosed of the type wherein an unclamped conducting transistor in each of a plurality of memory cells connected to a given word line is driven into saturation when storing data. The cell is equipped with controlled active devices for discharging the saturation capacitance of the conducting transistors prior to writing new data into the cells. Each active device is characterized with a forward low-impedance current direction and reverse high impedance current direction therethrough for each saturation transistor. Each active device is connected to discharge an associated saturation transistor in its forward current direction. In one embodiment, each active device discharges to a word line when the line is brought to an appropriate control potential. In another embodiment, each active device discharges to a separate discharge line not connected to the work line when the former line is brought to an appropriate control potential. The active devices may be diodes. In yet a further embodiment, the active devices may comprise diodes with leaky reverse bias characteristics. These diodes, in their reverse bias current direction, may be used as the memory cell loads. Alternatively, a PNP transistor may be used as the memory cell load. Resistors may be included in the discharge line to prevent word line-bit line voltage clamping.

Memory cell with active device for saturation capacitance discharge

A phase splitter with latch comprises a true complement generator in the form of a current switch (T1, T2, T3, R3) which supplies two complementary output signals in response to an input signal (VIN). The outputs of this true complement generator are in each case connected to an associated emitter follower (T4, T5). The two emitter followers (T4, T5) have identical emitter resistors (R6, R7) which simultaneously serve as collector load resistors of two cross-coupled transistors (T6, T7) also comprise identical but higher emitter resistors (R13, R14) than the emitter followers (T6, T7). The emitters of the cross-coupled transistors (T6, T7) are each connected to one of the two inputs of an output stage (T8, T9, T11) consisting of a current switch. This current switch is connected to operating voltage (VEE) through a clock-controlled transistor (T11). Upon actuation of the output stage, i.e., when transistor (T11) is on, the active emitter resistance of one of the cross-coupled transistors (T6, T7) is pulled below the value of the emitter resistors (R6, R7) of the emitter followers (T4, T5), thus causing the latch circuit to be latched as a function of the input signal.

Phase splitter with latch

Disclosed is a phase splitter with integrated latch circuit, where the complementary output signals generated after an input signal applied to a true-complement generator are available directly without any load by the latch circuit, where upon a premature change of the input signal there is no undesired change of the previously set switching state or of the output signals, respectively, and where a simple clocking for functional control can be used. The advantages presented by the disclosed Phase splitter substantially consist in that the speed with which the complementary output signals are supplied is extremely high since the output signals are available directly, i.e. with only one stage delay, the latch circuit being non-conductive in the stationary state, and thus in a latching process does not have to be switched from one stage to the other, but only switched on.

Phase splitter with integrated latch circuit

After a controlled strong lowering of the word line potential for the purpose of addressing a cell, said potential is immediately recharged simultaneously increasing the potential on the N side of the two PNP injectors of the cell and causing the injector capacitances of the selected storage cells and the bit line capacitances to form a capacitive voltage divider, so that the bit lines connected thereto are recharged to different degrees by the different magnitudes of the injector capacitances. Thus, the differential signal formed on the bit lines is noticeably amplified by the supply of currents of different magnitudes.

Circuit arrangement for capacitive read signal amplification in an

Semiconductor storage in which the current necessary for reading and/or writing the storage cells is generated simply by discharging input capacitances of the non-selected storage cells and is fed directly to the selected storage cells for reading and/or writing.

Method of and circuit arrangement for reading and/or writing an

An integrated semiconductor memory having memory cells which have (or are designed to have) inherent asymmetrical access times for the distinguishable memory states thereof. The memory is operated on the basis of the shorter access time. This is accomplished by utilizing an oppositely asymmetrical sense system, preferably in the form of a pre-set sense latch. For example, in the case of a digital memory with the reading of a '0' state having a shorter access time than the reading of a '1' state, at the beginning of a read operation a sense latch is set to the (slower) '1' state. Thus, only in the case of reading a '0' is the state of the latch changed to the '0' state. Thus, the actual access time is no longer determined by the longer access time, namely, the reading of a '1'. The access time is determined by the shorter access time, namely, the reading of a '0'. The concept may also be used if the sense latch has an asymmetric access time. Then it is advantageous to intentionally choose a corresponding asymetrical memory cell design.

Integrated semiconductor memory and method of operating same

In an integrated circuit an improved highly integrated semiconductor structure for providing a Schottky diode-resistor circuit configuration is disclosed. Although not limited thereto, the improved highly integrated semiconductor structure has particular utility when employed in a monolithic memory.

Highly integrated semiconductor structure providing a diode-resistor

A memory storage system which utilizes semiconductor storage cells comprised of cross-coupled bipolar transistors arranged in a memory system array with an error reference circuit and a standby reference circuit that is controlled by a clock signal. The standby reference circuit and the error reference circuit are both coupled to the bit lines and selectively control a restore circuit that maintains, in the standby state, a selected potential on the bit lines such that short access times are realized and current is prevented from flowing into unselected cells when adjacent defective cells are being read or written.

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Schoenaich, Germany

Friedrich C Wernicke