Abstract: A BiCMOS logic circuit having greater drive and speed at low voltage is provided. The logic circuit includes a switching device which allows the pull-down device of the logic circuit to be driven directly by an input signal without first having to switch a MOS device. The switching device conducts current between the input terminal of the logic device and the pull-down device when the output signal equals a certain value.

Abstract: A carry logic circuit for a programmable logic device which uses a single function generator to create a carry propagate signal (P) and an output signal (S). The function generator includes a plurality of signal generation circuits, each of which is controlled by a first input signal (A) and a second input signal (B). One of the signal generation circuits is programmed to provide a desired carry propagate signal (P) in response to the first and second input signals (A,B). The carry propagate signal (P) is transmitted for use outside of the function generator to perform a carry propagation function for the carry logic circuit. The remaining signal generation circuits are programmed to generate one or more intermediate output signals in response to the first and second input signals (A,B). These intermediate output signals, in combination with carry propagate signal (P), are representative of the desired output signal (S).

Abstract: An improved local clock driver for locating race conditions within a integrated digital circuit. Highly integrated digital circuits have many local circuits and each local circuit has a local clock driver. The local clock driver strengthens and distributes a clock signal within the local circuit. The improved local clock driver introduces a controllable delay circuit in all the local clock drivers of the digital integrated circuit. By selectively delaying each local clock driver, clock skew problems that cause race conditions can be located. To compensate for such race conditions caused by clock skew problems, the delay circuit can be turned on in the receiving local block circuit.

Abstract: A signal transmitting circuit includes one or more circuit blocks having a driving circuit and an intra-block transmission line for transmitting a signal produced by the driving circuit, one or more circuit blocks having a receiving circuit and an intra-block transmission line for transmitting the signal to said receiving circuit, and a main interblock transmission line for propagating a signal between both of the driving and receiving circuit blocks. Inter-block transmission line is terminated at one or two ends by one or two resistors having substantially the same impedance as the interblock transmission line itself.

Abstract: A integrated circuit buffer includes a first inverter comprising a pull-up transistor of a first conductivity type (e.g., p-channel) and a pull-down transistor of a second conductivity type (e.g., n-channel) for driving a load. The buffer further includes a second inverter comprising a pull-up transistor of the second conductivity type (e.g., n-channel) and a pull-down transistor of the first conductivity type (e.g., p-channel) that also drives the load. The first and second inverters are driven by a drive circuit that provides signals that are substantially out of phase. Therefore, in operation the pull-up transistors are active during a first time period, and the pull-down transistors are active during a second time period. In this manner, the drive capability of the buffer is improved in the face of voltage bounce on the power supply bondpads, which is typically due to package inductance.

Abstract: A hierarchical switch matrix in a very high-density programmable logic device (CPLD) interconnects a multiplicity of programmable logic blocks in the CPLD. A new level of functionality coupled with high speed is provided by the hierarchical switch matrix. The hierarchical switch matrix includes three levels, a global switch matrix, a segment switch matrix and a block switch matrix. The block switch matrix provides a high speed signal path for signals within a programmable logic block. The segment switch matrix provides a high speed means of communication for signals within a segment, while the global switch matrix provides a high speed path for communication between segments. The hierarchical switch matrix of this invention provides a fixed, path independent, uniform, predictable and deterministic time delay for each group of signals routed through the hierarchical switch matrix.

Abstract: A latch circuit has an enable circuit responds to clock pulse levels of a first polarity by outputting an enabling voltage of a second polarity opposite to the first polarity. The latch circuit also has first and second inverters which each have an output, a first biasing input connected to a first polarity voltage, a first input, a second a biasing input receiving the enabling voltage from the enable circuit and a second input. When enabled by the enabling voltage, each inverter drives its respective output to a voltage of the first polarity in response to receiving a signal of the second polarity at its first input. Alternatively, when enabled, each inverter drives its respective output to a voltage of the second polarity in response to receiving a signal of the first polarity at its second input. The first input of the first inverter receives, between the leading and trailing edges of the first polarity clock pulse levels, a signal to be stored.

Abstract: A programmable logic device (10) has a number of programmable logic elements (LEs) (12) which are grouped together in a plurality of logic array blocks (LABs) (14). An LE incorporates a plurality of partitioned look-up tables (40a, 40b) that may be selectively connected to its inputs and outputs by means of a number of multiplexers (44a-d, 46). Shared LAB-wide input lines (43a, 43b) provide a shared input line into a number of LEs in a LAB. A digital information processing system (500) incorporating the invention is disclosed. A wide-input AND gate (74) combining the outputs of a number of LEs is disclosed.

Abstract: A field programmable gate array having independently buffered output lines of a CLB for handling critical path situations. One of the CLB's output ports is coupled to a vertical interconnect line and a horizontal interconnect line. Two separate buffers are used to drive these lines. One buffer drives the horizontal interconnect line, while the other drives the vertical interconnect line. One of these lines is used to conduct the output signal that corresponds to the critical path. The other line is used to conduct the output signal onto other branches that are not part of the critical path. Hence, by using a separate buffer to drive the critical path, it is not loaded with the circuits associated with the non-critical branches.

Abstract: In order to provide a detector with fewer switching elements for detecting simultaneous occurrence of more than one of logic `1` or logic `0` out of plural inputs, 4 inputs A, B, C and D for example, a detector of the invention detects more than one of logic `1` from NAND logic of outputs of 3 OR-NAND composit gates as follows. ##EQU1## Each OR-NAND composit gate is composed of 4 pMOS transistors for common use and 4 nMOS transistors and a NAND gate of 3 inputs is composed of 3 pMOS transistors and 3 nMOS transistors.Therefore, the detector of 4 inputs of the invention can be composed of 22 MOSFETs insted of 36 MOSFETs needed for a conventional detector of 6 NAND gates of 2 inputs and a NAND gate of 6 inputs.

Abstract: A logic circuit comprises an output line, a first switch having an end connected to the output line and another end connected to a power source potential, a second switch having an end connected to the output line and another end connected to a ground potential, and a switching/rectifying circuit, which has an end connected to the output line and another end connected to an intermediate power source potential, for switching/rectifying, in which said intermediate power source potential is higher than the ground potential and lower than the power source potential. With this configuration, said switching/rectifying circuit includes a third switch and a rectifier connected in series.

Abstract: A block clock and initialization circuit for a programmable logic block in a complex very high density programmable logic device generates a plurality of block clock signals and block initialization signals for elements in the programmable logic block. The block clock and initialization circuit includes a block clock generator circuit and a block initialization circuit. The block clock generator circuit receives a first set of product terms in a plurality of product terms and a plurality of clock signals as input signals. In response to the input signals, the block clock generator circuit generates output signals on a plurality of block clock lines. The block initialization circuit receives a second set of product terms in the plurality of product terms as input signals. In response to the input signals, the block initialization circuit generates a plurality of output signals on the block initialization lines.

Abstract: A dynamic clocked inverter latch with reduced charge leakage includes a first node biasing circuit with a P-MOSFET and an N-MOSFET totem-pole-coupled between VDD and an output node, and a second node biasing circuit with another N-MOSFET and another P-MOSFET totem-pole-coupled between the output node and VSS. The first P-MOSFET receives an input data signal and the first N-MOSFET receives a clock signal and in accordance therewith together cause the output node to charge to a charged state having a charge voltage associated therewith. The second N-MOSFET also receives the input data signal while the second P-MOSFET receives the inverse of the clock signal and in accordance therewith together cause the output node to discharge to a discharged state having a discharge voltage associated therewith.

Abstract: A programmable logic device (PLD) cell is used to construct a high density high performance programmable logic device (PLD). The PLD cell includes two programmable logic block cells. The PLD cell also includes an I/O cell and an input macrocell. In addition the PLD cell includes a sub-bank of a programmable output switch matrix bank and a sub-bank of a programmable input switch matrix bank. Each programmable logic block cell includes a multiplicity of product terms. At least one product term in the cluster is programmably available to the cluster. When the product term is disconnected from the cluster, the product term is used for control of the polarity of the logic macrocell output signal or asynchronous functions. Thus, the programmably connectable product term can be used for either synchronous or asynchronous operations. If the programmably connectable and disconnectable product term is connected to the product term cluster, the programmable logic block cell is used for synchronous operations.

Abstract: A logic circuit combines a plurality of pass-transistor logic trees and a multiple-input logic gate for receiving intermediate logic signals from the respective pass-transistor logic trees, and can express a complex logical operation while decreasing the number of stages in pass-transistor logic trees and improving operation speed. Even a logical operation that cannot be expressed efficiently by a known or conventional pass-transistor logic circuit can be expressed efficiently with performance higher than that of a known CMOS logic circuit. Furthermore, when a static feedthrough current of the multiple-input logic gate is suppressed, power consumption can be reduced. In some embodiments, since circuitry for suppressing a static feedthrough current of the multiple-input logic gate is arranged so that a probability of occurrence of logical collision with a preceding stage will decrease or will be nil, power consumption can further be reduced.

Abstract: The present invention provides an output buffer on a monolithic integrated circuit with programmability, such that one of sixteen output configurations is selected for providing the proper signaling interface to peripheral devices. An input signal (SELECT) in selector circuit (12) provides the transfer of one of two sets of input data signals into function control circuit (14). With the input signal (EN) applied, control signals in the function control circuit (14) set the configuration mode for the output buffer circuit (16). The data input signal INPUT DATA, in accordance with the programmed configuration mode for the output buffer circuit (16), transitions the output signal, DBOUT. The output buffer circuit (16) is programmable for providing an open-drain output, a tri-stated output, a high current output, a low current output, a PCI output, and an output selected from two operating voltages for signal level translation functions.

Abstract: A wired combinational logic arrangement responsive to N binary signal sources includes N circuits, one for each source. The circuits drive a common output terminal. Each circuit includes first and second devices for pulling the common terminal to first and second different voltages during successive abutting activation periods. The first device supplies a current to the common terminal that is considerably greater than the current supplied to the common terminal by the second device. The arrangement further includes a third device for pulling the common terminal to the second voltage at all times. The third device supplies a current to the common terminal that is either equal to or less than the current supplied by the second device.

Abstract: The pulse output circuit device comprises two transistors (2, 4) for constructing an output buffer, a transistor (7) connected between the output line (OUTP) of the output buffer and the high potential supply voltage (VDD), a transistor (8) connected between the output line (OUT) of the output buffer and the low potential supply voltage (GND), a control circuit (39) for applying a gate signal to the transistor (7), and a control circuit (40) for applying a gate signal to the transistor (8).

Abstract: An FPGA architecture is provided which uses logic unit output lines of more than one length and provides extension lines to increase the reach of a logic unit output line. The architecture allows extremely fast connections between one logic unit and another. Also, all logic unit output lines drive about the same number of buffered programmable interconnection points (PIPs) so that the signal delay between one logic unit and the next can be predicted regardless of the functions and routing which have been selected by a user. The frequency of PIPs decreases as distance from the originating logic unit increases. This has the benefit of cooperating with software which tends to place interconnected logic in close proximity. The architecture is preferably implemented with a tile layout with one logic unit in each tile, and logic unit input and output lines extending through several tiles. Thus one tile boundary is like another and there is minimum hierarchy.

Abstract: Depletion mode pass gates utilized in a PLD to enable a gate voltage of Vcc to be applied for turn off, as opposed to a higher voltage required for enhancement type devices. With Vcc applied for turn off, gate oxide stress is reduced and chip reliability increased. A decoder utilizing PMOS transistors is further used to supply a negative gate voltage to enable turn off of the depletion mode pass gates. In one embodiment, to prevent pumping the power supply voltage above Vcc when supplying Vcc to gates of the pass gates, the decoder is an all PMOS device using PMOS transistors to connect Vcc to gates of the pass gates. In another embodiment both NMOS and PMOS transistors are utilized, with PMOS blocking transistors utilized to prevent a negative voltage from being applied to the NMOS transistors and causing current leakage. A negative voltage pump is further provided to supply a sufficient negative voltage.