Abstract: This invention relates generally to the accessing of random access access memory arrays and, more specifically to circuits and techniques for increasing the data valid time of such memory arrays without increasing either the access or cycle times of the array. This is accomplished by providing, during a read cycle, a read signal directly to an output driver and simultaneously providing, via a parallel path, a latch output to the same driver. The latch output is provided under control of the read signal and a returning portion of a clock pulse such that the latch output overlaps the direct read signal from a read/write amplifier. An output is provided from the latch until it is reset and may last well into the next read cycle even when a new read signal is present.

Abstract: This invention relates generally to the static, random access, semiconductor memory arrays which incorporate split-emitter memory cells. The latter are accessed during a read cycle of a selected memory cell by precharging all the bit lines of unselected memory cells associated with the word line of the selected cell. This is accomplished by switchably connecting a voltage source to all the unselected bit lines which charges their bit line capacitances. Then, when read current sources are switchably connected to both the selected and unselected memory cells and the associated word line is switched to a WORD SELECT source, the read current associated with the unselected bit lines flows via charging switches to the precharge voltage sources and the read current associated with the selected bit lines along with dynamic current from uncharged selected bit line capacitances flows into the selected cell.

Abstract: The memory cell array is one in which the bit lines associated with each column of double-ended memory cells are interleaved with the bit lines of adjacent columns of memory cells. Because the spacing of metallic bit lines is governed by certain ground rules, cell length in the x-dimension could be reduced no further as long as metallic interconnections were used. To overcome the spacing limitation of metallic interconnections, polycrystalline fingers or extensions are substituted for metal cross-coupling interconnections. The latter in conjunction with metallic straps which are shorter than the widths and spacing of two metallic interconnection lines provides a significant reduction in the x-dimension and hence in cell area. The method and structure taught may be utilized with both bipolar and unipolar devices.

Abstract: A technique for making ohmic electrical interconnections between semiconductor regions of opposite conductivity type, without requiring metallic interconnection lines. This technique has applicability in any circuit using bipolar devices, and in particular is useful to provide a very dense static memory array of bipolar transistors. To join the opposite conductivity regions, intermediate layers are formed including a silicide of a refractory metal, such as W, Mo, Ta, etc. and at least one layer of doped polycrystalline semiconductor material. For a single crystal of silicon having N and P type regions, the refractory metal silicide forms an electrical connection to at least one doped polysilicon layer of a first conductivity type and to either a single crystal semiconductor region of the opposite conductivity type or to another polysilicon layer which also has the opposite conductivity type.

Abstract: Design/test technique to facilitate improved long-term stability testing of static memory arrays with high inherent data retention characteristics at extremely small standby current requirements. The test concept is based on the fact that defects in the standby condition system of a memory array have a bearing on the word line standby potential. Detection of word line potentials differing from their nominal value defined for the standby state, i.e., in the unselected operation mode, is accomplished by performing a disturb write operation into the partly or totally unselected array. As a result cells along a defective word line are less disturbed than those along a goood or normal word line. This inverted error pattern is used for screening defect word lines which otherwise would show up as long-term data retention problems.

Abstract: A memory structure for very large memory arrays on a chip is described where the memory array is divided into a number of subarrays. The subarrays are controlled via common word decoders and subarray decoders. The word lines of the individual subarrays are individually selectable through word line switches, and the bit lines of the subarrays are applied directly to a common line system, and interconnected in such a manner that the peripheral circuits, e.g. the data input and output circuits, can be arranged in practically any free location on the chip.

Abstract: A bipolar logic circuit with superior speed/power characteristics is described. Circuit operation is based on a unique dynamic minority carrier charge exchange mechanism between the input diodes performing the logic and the oppositely poled level shift diode(s) at the input of the transistor output stage. To accomplish this, the input or logic diodes as well as the level shift diode(s) are laid out as large .tau..sub.s diodes with .tau..sub.s being the minority carrier charge storage time constant. Thus, despite very small dc currents during static operation (resulting in an extremely small dc power dissipation) high dynamic switching currents for turning-off as well as for turning-on the output transistors are achieved.

Abstract: A semiconductor memory is described, whose word lines are divided into several partial word lines or partitions, wherein each partial word line is connected to a word switch and all word switches of a word line are selected and controlled via a first word control line and a second word control line.

Abstract: A memory is described comprising static MTL memory cells for high operation speeds. The cell or primary injectors and the bit line injectors are coupled to each other by an angular injection coupling via the low-resistivity base region of the cell flip-flop transistors. This results in a signal path with reduced series resistance and thus higher signals and a faster read operation obtainable. The density is additionally increased by using in common the primary injectors and the bit line injectors of adjacent cells of the array.

Abstract: A method of and a circuit arrangement for reading an integrated MTL(I.sup.2 L) store are described, wherein prior to or during a read operation, line capacities are discharged and in addition to the word line drivers and the bit line drivers, a read/write circuit is provided. Simultaneously with the selection of a word line (WL) or with a slight time delay (t1), two identical current sources (IRD0) are connected by means of two switches (S0 and S1) to the relevant bit lines (B0 and B1). As a result, the two injectors of the two bit line PNP transistors (T1 and T4) are supplied with the same currents. In a second phase (t2), the current sources (IRD0) are switched off so that the duration of the second time phase (t2) considerably exceeds the storage time constant (.tau.e) of the bit line PNP transistor (T4) connected to the switched "OFF" NPN transistor (T3) of a cell. The effective storage time constant (.tau.

Abstract: A Transistor-Transistor Logic (TTL) gate is disclosed wherein a different amount of base current is applied to the inverter transistor than is applied to the base of the output transistor. In one embodiment, a current mirror circuit controls the amount of base current flowing between the input transistor collector terminal and the base terminal of the inverter transistor to an amount less than that flowing between the input transistor collector terminal and the base terminal of the output transistor. In another embodiment, a resistor in series with the base of the inverter transistor performs the same function as the current mirror circuit.

Abstract: A vertical pair of complementary, bipolar transistors is disclosed which includes a semiconductor substrate of one conductivity type and a pair of dielectric isolation regions disposed in contiguous relationship with the substrate. An injector region of opposite conductivity type is disposed between the pair of isolation regions. A pair of heavily doped, polycrystalline, semiconductor regions of the one conductivity type is disposed over and in registry with the pair of isolation regions. Similarly, a single crystal, semiconductor region of the one conductivity type is disposed over and in registry with the injector region. Finally, a first zone of opposite conductivity type is disposed in the single crystal region and a second zone of the one conductivity type is disposed in the first zone.

Abstract: A multiaddressable highly integrated semiconductor storage is provided, the storage locations of which are addressable by several independent address systems for parallel reading and/or writing. The storage locations are each made up of n storage elements. One storage location consists, for example, of at least two flip-flops which, via coupling elements are connected to associated separate bit and word lines. Each storage location has at least three independently selectable or addressable entry/exit ports permitting the following operations to be executed in parallel: Read word A, read word B, write word C as well as any combination of two or individual ones of those operations. The number of read ports can be increased by providing further address systems and by substituting triple, quadruple, etc., storage cells for a cell pair.

Abstract: Monolithically integrated storage arrangement with storage cells arranged in a matrix and consisting of two cross-coupled I.sup.2 L structures (T1, T2 and T1', T2') each in the manner of a flip-flop, wherein the read signal is derived from the charge carrier current reinjected into the injection zone (P1 or P1') of the respective conductive inverting transistor (T1 or T1') and thus into the connected bit line (BL0, BL1). The storage cells of a matrix line are selected via a common address line (X) coupled to the emitters (N1, N1') of the inverting transistors (T1, T1') of said storage cells.In spite of the fact that the structures have minimum area requirements, a high read signal is obtained by subdividing the address line (X) into two partial word lines (X1, X2). One partial word line (X1) is connected to all emitters (N1) of the inverting transistors (T1) of one I.sup.2 L structure of all storage cells of a matrix line.

Abstract: A semiconductor circuit in which a plurality of transistors is provided, the collector regions/contacts and the base regions/contacts of the transistors being mutually self-aligned. In one embodiment, the collectors have conductive layer contacts (such as metal) and are self-aligned to polysilicon base contacts while in another embodiment the base contacts are comprised of a conductive (metal) layer while polysilicon is used for the collector contacts. The collectors of these transistors can be butted to a field oxide to reduce the extrinsic base area and to minimize excess charge storage in the base region. The base contacts, whether polysilicon or metal, etc. provide alternate base current paths so that the removal of the extrinsic base area does not adversely affect the total amount of base current which can flow.

Abstract: Disclosed is a restore circuit for restoring an integrated semiconductor storage array having storage cells consisting of bipolar transistors. The restore circuit includes a reference voltage generator, an impedance converter, and switches to connect the reference voltage generator and the impedance converter to the storage array. The reference voltage generating circuit includes a current source and at least one reference storage cell identical in construction to the storage cells of the array. The reference voltage generating circuit provides a reference voltage to the impedance converter which supplies a second reference voltage to the array at a greatly reduced impedance. The equivalent circuit of the storage cells is that of a capacitor in parallel with a diode. Thus, the impedance converter provides an initial surge of capacitive current which restores the cells, followed by a standby current which is a function of the diode characteristics of the cell equivalent circuit.

Abstract: A method and arrangement is provided for selecting and discharging a pair of bit lines of a plurality of charged pairs of bit lines of a memory circuit having cells of the merged transistor logic type. A selected pair of bit lines is discharged through a selected cell coupled to the selected pair of bit lines while simultaneously the remaining or non-selected pairs of bit lines are discharged through a common switch into non-selected word lines.

Abstract: Disclosed is a simulated storage cell structure for use as a reference voltage generator in a semiconductor store fabricated in Merged Transistor Logic (MTL) technology. The simulated storage cell structure includes n elongated regions of P-type diffusion arranged in parallel to each other in an N-type trough of semiconductor material. The elongated P-type regions are alternately designed as collector and Injector strips.

Abstract: An inverter is disclosed which includes a fast turn-on circuit and a turn-off circuit comprising a standby current source and a parallel circuit of a diode and capacitor connected to the input of a bipolar transistor. Standby current plus an input transient applied via the charged capacitor cause high speed turn-on of the bipolar device. The diode having a lower threshold than the bipolar base-emitter diode switches when a turn-off transient is applied to the bipolar device shunting standby current which held the bipolar in the conducting state to ground via the conducting diode.

Abstract: In integrated semiconductor memory cell arrangements, particularly integrated semiconductor memory cell arrangements using merged transistor logic configurations, line capacitances are discharged before accessing to reduce access time and power consumption. Individual bit line transistor switching means are coupled to each bit line to provide a discharge path for the line capacitances associated therewith. Common transistor switching means are coupled to each individual bit line transistor switching means to commonly discharge the individual discharge currents received from each individual bit line transistor switching means. Individual word line transistor switching means are also connected to respective word lines to distribute the current passing through the common transistor switching means to the respective word lines. The discharge circuit arrangement permits minimum-area bit line and word line transistor switching means.