Abstract: An ECL output buffer circuit is constituted by an output buffer circuit main portion and its control circuit. In the output buffer circuit main portion, an output from a differential switch is input to the base of a bipolar transistor (emitter follower). The emitter of the bipolar transistor is connected to an output terminal. A ground potential is applied to the collector of the bipolar transistor. One end of the channel conductive path of a MOS transistor is connected to the base of the bipolar transistor. The other end of the channel conductive path is connected to a power-supply terminal via a constant-current source. The control circuit controls the ON/OFF operation of the MOS transistor and the output level of the bipolar transistor. When the output buffer circuit main portion is to be set in a standby state, the control circuit performs control to set the MOS transistor in an ON state and set the output of the bipolar transistor at low level.

Abstract: A translator circuit (21) converts an ECL logic level to a TTL logic level. The translator circuit (21) operates at high speeds, rejects power supply noise, and does not use Schottky diodes for preventing transistors from saturating. The translator circuit comprises a differential input stage (22), a level shift stage (23), a differential stage (24), and an output stage (25). The differential input stage (22) is responsive to an ECL signal and provides a differential output signal. The level shift stage (23) level shifts the differential output signal of the differential input stage a predetermined DC voltage. The differential stage (24) is responsive to the level shift stage (23) and generates first and second output signals. The differential stage (24) rejects power supply noise coupled from the level shift stage (23).

Abstract: According to the present invention, integrated circuitry provides for the ability to selectively introduce delays into the timing of the integrated circuit, without the expense and time associated with methods used in the prior art. As a minimum, a fuse element having at least one fuse and a transistor element having at least one transistor are placed in parallel to each other between a voltage supply of a gate of the integrated circuit and a corresponding voltage supply of the integrated circuit. When the fuse element is intact, the fuse element provides a relatively low resistance path from the voltage supply of the gate and the corresponding voltage supply of the integrated circuit. However, upon blowing the fuse element, this low resistance path is no longer available. An increased resistance path through the transistor element must be used, and the integrated circuit is slowed down accordingly.

Abstract: Programmable circuitry (10) is provided including a plurality of logic modules (12) each having at least one input conductor (16). A nearest neighbor conductor (36) is fusibly coupled to output circuitry (25) of a selected logic module (12), the nearest neighbor conductor (36) intersecting the input conductor (16) of a nearest neighbor logic module (12). A fuse (40) disposed at the intersection of the nearest neighbor conductor (36) and the input conductor (16) of the nearest neighbor logic module (12) is provided for selectively establishing electrical coupling therebetween.

Abstract: An I/O buffer is provided that is noise-isolated, i.e., less susceptible to the effect of switching noise. In particular, a noise isolated I/O buffer includes an output terminal, a transient switching circuit connected to first power and ground voltage sources, to a logic input signal and to the output terminal, and a logic holding circuit connected to second power and ground voltage sources separate from the first power ground voltage sources, to the logic input signal and to the output terminal. The transient switching circuit causes a logic level of the output terminal to be switched responsive to a change in the input signal. The logic holding circuit causes the logic level of the output terminal to be maintained in the absence of a change in the input signal. In the absence of a change in the input signal, the transient switching circuit may be turned off, therefore presenting a high impedance to the first power and ground voltage sources.

Abstract: Apparatus for converting superconductor low level signals to semiconductor signal levels utilizing a continuous superconductor to semiconductor converter circuit biased for maximum gain and without the need for a clocked reset signal. Employing a unique biasing arrangement utilizing two capacitors and one transistor, this circuit has long term bias voltage retention and good power supply noise rejection ratio.

Abstract: Noise on address lines is prevented from causing incomplete preparation for reading data after an address transition is detected. One ensures that a flash memory device reads correct data by guaranteeing that each address transition detection, including false address transition detections caused by noise, permits sufficient preparation to read data reliably. An address detected pulse is generated whenever at least one bit of an address changes. If noise causes an invalid address transition detected pulse that is too short to occur, the short pulse will be extended to permit preparation for the memory to be read. Input summation circuitry receives an input pulse and combines the input pulse with a feedback signal to form an input sum signal. Feedback circuitry receives the input sum signal and outputs the feedback signal to the input summation circuitry. The feedback signal holds the input sum signal until the feedback circuit is reset.

Abstract: A level conversion output circuit includes two level conversion circuits for "high" and "low" logic signals, each of which includes a first CMOS inverter operating between an internal power supply of 3.3 V and ground, and a second CMOS inverter operating between an external power supply of 5 V and ground. One of the level conversion circuits is provided with an additional p-MOS transistor so that a 5.0 V voltage is applied to a gate of a p-MOS transistor of the second CMOS inverter from the external power supply through the additional p-MOS transistor, when the p-MOS transistor of the second CMOS inverter is controlled to be turned off.

Abstract: A variable speed digital signal reproducing apparatus, particularly related to low speed reproduction of a digital signals recorded in a recording medium. The apparatus includes a unit for determining whether a reproduction PCM signal is renewed or not. Based on the renewal determination, PCM data of one frame is stored in a memory and the PCM data is read at a frequency rate corresponding to a tape reproducing speed at that time. Furthermore an interpolating device operates on the read PCM data to produce a PCM signal having the same frequency with which the PCM signal was read from the memory means.

Abstract: A digital logic circuit is provided which eliminates excessive power consumption while providing high speed transitions between logic states. The digital logic circuit includes a pull-down device coupled to an input line. The digital logic circuit further comprises a weak pull-up device and a strong pull-up device coupled to the pull-down device at a node. A means for providing a signal on an output line of the programmable logic device is coupled to the pull-down device and the pull-up devices. The weak pull-up device holds the node high if the pull-down device is in an off state. However, if the pull-down device is in an on state, the strong pull-up device is also turned on, thereby providing a stable intermediate voltage on the node. A feedback path from the output line controls the state of the strong pull-up device.

Abstract: An open drain output circuit includes a package having a reference potential section on at least a portion thereof. An output terminal of the circuit disposed on the package is connected through a load resistor to an external power supply. A common terminal also disposed on the package is connected to an external point of reference potential. A parasitic load capacitance is formed between the common terminal and the load resistor. A field effect transistor having drain, source and gate regions is disposed within the package. The drain and source regions are connected to the output and common terminals, respectively. The conductivity of the drain-source conduction path is variable in accordance with the value of a control voltage applied between the gate and source regions. Connections of the drain and source regions to the output and common terminals, respectively, provide parasitic inductances.

Abstract: A multiplexer configuration includes at least one first and one second group of transistors each including one first, one second and at least one third transistor. Current sources are connected to a first supply potential terminal and emitters of the transistors of each respective one of the groups are connected to one another and to a respective one of the current sources. A first resistor has one terminal connected to a second supply potential terminal and has another terminal and collectors of the first transistors of each respective one of the groups are connected to one another and to the other terminal of the first resistor. An output terminal is connected to the other terminal of the first resistor. Bases of the second transistors of each respective one of the groups are input terminals for a respective data signal. Bases of the third transistors of each respective one of the groups are terminals for a respective selection signal. The selection signals are mutually complementary.

Abstract: The low-power two-stage data output buffer (20,70) includes a two-stage switching circuit (50, 72) that drives an n-channel pull-up transistor (24) in two stages, thus only using current from the pumped high voltage supply during the second stage of the operation. The two-stage switching circuit (50, 72) first drives the pull-up transistor (24) with the supply voltage, V.sub.DD, then drives it with the pumped high voltage supply, V.sub.PP. A feedback circuit, coupled between the output node (28) and the two-stage switching circuit (50, 72), generates a path from the high voltage supply, V.sub.PP, to the n-channel pull-up transistor (24) in response to the supply voltage level appearing on the output node (28), and blocks the path from the high voltage supply, V.sub.PP, to the supply voltage.

Abstract: A macrocell for use in a programmable logic device (PLD) providing for enhanced logic capability and reduced setup time. The preferred embodiment of the macrocell includes two look-up tables, for increased fan-in, and two flip-flops that increase fan-out, thereby doubling logic capability of the PLD without unacceptably increasing device size. Doubling the register count makes this PLD particularly suitable for applications employing high density sequential logic. Furthermore, a second register can be used for receiving fast input signals form an input to the PLD to reduce setup time.

Abstract: A field programmable gate array (10) having a plurality of logic modules (31-35) has a pair of driver circuits (51-52) connected between each logic module (31) and logic module interconnection tracks or lines (12-16, 20-23) (51-52). Each of the drivers (51-52) has an input connected to receive a common output signal from the associated logic module (31). The output from each of the driver circuits (51-52) is selectively connectable to one of the interconnection tracks by a different respective antifuse (27). The output of each driver circuit (51-52) has a current magnitude less than a level that would damage the antifuse (27) but greater than a predetermined level, so that the track capacitances can be charged as rapidly as possible to increase the propagation time of a signal in the array. In one embodiment (10), the respective logic module interconnection lines or tracks 12 to which the pair of antifuses are connected are different logic module interconnection lines (12, 13).

Abstract: A driver circuit in an integrated circuit includes a flip-flop circuit and a plurality of AND gates. The flip-flop circuit causes an external control signal which is supplied externally to synchronize with a clock signal, and produces an internal control signal. The AND gates control a plurality of outputs based on a data signal in accordance with the internal control signal. Since the internal control signal is synchronized with the clock signal, changes in the outputs from the AND gates are delayed from the timing of the clock signal. Thus, it is possible to prevent the occurrence of malfunction caused by a switching current to flow in transient of changes in the outputs.

Abstract: There is disclosed herein a method and apparatus for distributing high speed clock signals on an integrated circuit while eliminating clock skew. The invention is particularly useful in field programmable gate arrays where the signal paths are defined by the user after the integrated circuit leaves the place of manufacture and enables field programmable gate arrays to operate at clock speeds in excess of 200 MHz, a speed not previously attainable. Clock skew is eliminated by generating differential clock signals at each of four corners of the array from master differential clock signal delivered simultaneously to each of the four corners. The differential clock signals generated at each corner have ramps the rise time of which slightly exceeds the propagation delay of a clock signal traversing the array.

Abstract: A dubbing system for duplicating a tape-shaped recording medium on which an amount of information signals for a given period of time are recorded in each of many tracks having different azimuth angles between adjacent tracks includes a reproducing apparatus wherein N rotary heads (N: an integer which is at least 2) which have different azimuth angles between adjacent heads and rotate in a closely adjacent state are used for reproducing, as N channel signals, information signals from N adjacent tracks formed on a first tape-shaped recording medium, and a recording apparatus wherein N rotary heads which have different azimuth angles between adjacent heads and rotate in a closely adjacent state are arranged to receive the reproduced N channel signals and to record them on a second tape-shaped recording medium while forming N adjacent tracks on the second tape-shaped recording medium.

Abstract: This invention discloses a signal output circuit including DC and AC buffers having output nodes commonly connected to a signal output terminal, and an AC buffer control circuit for driving the AC buffer when an output from the DC buffer is changed and for controlling an output from the AC buffer in a high-impedance state when the output from the DC buffer is stationary.

Abstract: Cascode voltage switch (CVS) logic circuits include a CMOS logic tree having multiple logic branches and a bipolar, branch isolation transistor. Each logic branch of the logic tree changes state between a logic "1" and a logic "0", with a state change being manifested as a charging or discharging of the logic branch. The bipolar transistor comprises a multiple-emitter bipolar transistor wherein each emitter is electrically coupled to a different logic branch of the CMOS logic tree. A precharge circuit, coupled to the logic tree via the bipolar transistor, provides charge to an output of the CVS circuit prior to operation of said logic tree. The logic branches of the logic tree are charged and discharged substantially independently of one another thereby enhancing speed of the combinatorial logic circuit. Various circuit modifications and generalizations are also discussed.