Abstract: A differential receiver includes a feedback circuit connected between an output node and one common node of the differential receiver to reduce the bandwidth and reject noise for a specific interval of time. In operation, a differential receiver bias current is controlled responsive to an output signal at the output node. Bias current is turned on during a steady-state mode with respect to the output signal, and is turned off, for a given delay period, in response to a transition mode with respect to the output signal.

Abstract: A compensated Schmitt Trigger circuit for providing a monotonic hysterisis response, the circuit including a plurality of transistors connected in series and coupled to a common input signal at their control inputs, a feedback circuit connected to the output of the plurality of transistors, an inverter coupled to the output of the plurality of transistors and to the feedback circuit for providing a hysterisis response at higher supply voltage, wherein the feedback circuit includes at least one feedback element coupled between the output of said plurality of transistors and input of the inverter for providing a monotonic hysterisis response at the output node of the Schmitt Trigger circuit. The feedback elements are connected/disconnected by control signals that reflect the variations in PVT conditions, and the control signals are derived from the standard Input/Output circuits library for compensation.

Abstract: The present invention provides an improved Chua's circuit providing current mode operation, access to all state variables, minimum use of grounded passive elements, and freedom from passive component matching comprising a dual output current conveyer based inductor having one grounded terminal, a capacitor connected across the second terminal of said inductor, a resistor having one terminal connected to the second terminal of said inductor, the second terminal of said resistor connected to one terminal of a second capacitor the other end of which is grounded, and a pair of dual output current conveyers connected together to form a 2-terminal negative resistance having one terminal connected to ground and the second terminal connected to the second terminal of said resistance.

Abstract: A voltage translator circuit for low level to high level voltage translation includes a plurality of transistors coupled to an inverter for receiving a common input signal at an input node of the plurality of transistors and passing a translated output signal to the output node of the plurality of transistors. A latch circuit is connected between a first node at the output node of the plurality of transistors and a second node that is connected to a feedback element at an input side of the plurality of transistors to form a feedback circuit that minimizes static power dissipation.

Abstract: An improved on-chip storage memory and method for storing variable data bits, the memory including an on-chip storage memory system for storing variable data bits that has a memory for storing data bits, a wrapper for converting the memory into a first-in first-out (FIFO) memory, and a controller for performing operations on the memory. In operation, the memory is converted into a FIFO memory after storing data, and output logic selects data to be output in a serial manner.

Abstract: A method for finding a maximum volume and minimum cutset in a network of interconnected nodes is provided. The method is applicable to systems that can be reduced to such a network, including telecommunication networks, traffic networks, computer networks, layouts, hydraulic networks, etc. An equivalent network is derived by replacing all nodes other then the source and sink by two interconnected nodes. A conventional method applies an augmenting path algorithm that identifies a cutset. If the feasible cutset is not achieved then a reduced network is constructed by directly connecting the member nodes of identified cutsets to the source node and repeating the above process for the reduced network until a feasible cutset is achieved.

Abstract: An integrated Low Dropout (LDO) linear voltage regulator provides improved current limiting. A differential voltage amplifier compares an output voltage to reference voltage and controls a pass transistor to make the output voltage substantially match the reference voltage. This is accomplished by sensing the output voltage of the voltage regulator for application to a first input of the differential amplifier and coupling a second input of the differential amplifier to the reference voltage. A current sense transistor utilizes current mirroring techniques to sense the current passing through the pass transistor to the output. This sensed current is compared to a reference current. The result of that comparison is fed back to the differential voltage amplifier to in a manner that increases the apparently sensed output voltage in situations where the sensed current exceeds the reference current.

Abstract: A digital logic system includes a reset input for receiving a reset signal, and a clock input for receiving an externally generated main clock signal. An ancillary clock generator generates an ancillary clock signal. A clock selection multiplexer has a first input for receiving the externally generated main clock signal, a second input for receiving the internally generated ancillary clock signal, and an output for providing the externally generated main clock signal or the internally generated ancillary clock signal to a functional circuit. A resettable edge-triggered shift register has a first input for receiving the externally generated main clock signal, a second input for receiving the reset signal, and an output connected to the clock selection multiplexer for deselecting the internally generated ancillary clock signal and selecting the externally generated main clock signal after detecting a certain number of edges of the main clock signal following the reset signal.

Abstract: A boundary scan tester is provided for testing logic devices. The boundary scan tester includes a boundary scan register, a data decompressor, a data compressor, and a derived boundary scan register. The boundary scan register registers the applied test vectors and test responses of a logic device, and the data decompressor is coupled to an input of the boundary scan register for decompressing the applied compressed test vectors. The data compressor is coupled to an output of the boundary scan register for compressing the test responses, and the derived boundary scan register is coupled to an input of the decompressor and an output of the compressor for storing and shifting in/out the compressed test vectors and test responses.

Abstract: The present invention provides an output buffer providing multiple voltages including an arrangement of bootstrapping capacitors, and a charge replenishing mechanism which provides continuous pulses to the arrangement of bootstrapping capacitors, thereby, maintaining voltage on the bootstrapping capacitors.

Abstract: A configurable output buffer capable of providing differential drive having complementary pairs of CMOS transistors having a common output terminal and a common control terminal, and with the second terminal of each CMOS transistor connected to its corresponding supply terminal through a current source/sink.

Abstract: A digital circuit operating frequency characterizer provides a combination of frequency and duty cycle characterization. The digital circuit operating frequency characterizer includes a programmable frequency generator, a programmable edge variator, a test engine, and a control circuit. The programmable frequency generator provides one or more output signals, and the programmable edge variator is coupled to one or more outputs of the programmable frequency generator for adjusting duty cycle. The test engine uses the outputs from the programmable edge variator and/or programmable frequency generator to apply a defined test signal sequence to a circuit under test and produce a status output after evaluating the outputs received from the circuit under test. The control circuit is connected to the control inputs of the programmable frequency generator, programmable edge variator, and the status output of the test engine.

Abstract: An improved input buffer providing configurable single-ended and differential signaling capability, comprising an input signal comparator, a first pad connected to one input of the comparator. An internal reference voltage source may be connected to one terminal of a first selection switch. The second terminal of the first selection switch is connected to the second input of the comparator and one terminal of a second selection switch is connected to the second input of the comparator. Further, a second input pad is connected to the second terminal of the second selection switch. The invention also includes a mode selector that enables the first selection switch and disables the second selection switch for providing single-ended operation using the internal reference voltage source, or enables the second selection switch and disables the first selection switch for enabling differential operation or single-ended operation using an external voltage reference.

Abstract: A CMOS input buffer supporting multiple I/O standards and having a pair of NMOS and PMOS differential receivers, each having a first input connected to an input pad and a second input connected to a reference voltage, a first multiplexer connected to the control terminal of the current sink of the NMOS differential receiver and having one input connected to the positive supply terminal, and a second multiplexer connected to the control terminal of the current source of the PMOS differential receiver and having one input connected to the negative supply terminal or ground. The buffer further includes an inverter connected to a combined output of the PMOS and NMOS differential receivers and having an output connected to the second input of the first and second multiplexer, and a configuration storage bit for selecting the desired inputs of the first and second multiplexer, thereby supporting high speed standards as well as general purpose standards while reducing static power dissipation.

Abstract: An improved programmable logic device provides increased efficiency and enhanced flexibility in configuration of block memories and includes one or more memory blocks and a vertical shift register that receives the data to be loaded in the memory blocks. The PLD further provides a selection device for selecting the memory cells in the memory blocks that are to store the received data, and a control block for controlling the loading of the data in the memory blocks. The selection device includes an address counter connected to the input of an address decoder so as to enable the selection of addresses in the memory blocks.

Abstract: A Content Addressable Memory (CAM) cell is presented which provides for improved speed and enhanced reliability. The CAM architecture enables maximal conduction of one of the output series pass transistors in the case of a data mismatch during a search operation thereby producing a minimal voltage drop, low impedance path for charging the bootstrap capacitance at the enabled output controlled switch, and causes one of the series pass transistors to conduct for discharging the bootstrap capacitance at the beginning of the precharge period of the bit lines.

Abstract: An enhanced JTAG interface provides an additional clock output at any desired I/O port of a logic device during normal operation. The interface includes a boundary scan data cell associated with each I/O port that enables either input data to the I/O port in a normal mode or routes the boundary scan input data during a JTAG operation. A control cell is associated with each data cell for selectively enabling either a normal mode or a JTAG mode of the boundary scan cell. A set of JTAG instructions enable/disable JTAG operation and select JTAG functions. The boundary scan data cell is modified to incorporate a multiplexing arrangement to selectively route the JTAG clock to the I/O port when required. The control cell is modified to selectively enable/disable the routing of the JTAG clock in the boundary scan data cell. The JTAG instruction set is enhanced to incorporate instructions to select the desired I/O port and to enable the routing.

Abstract: A method and system for improved optimal mapping of LUT based FPGA's. The invention comprises performing a topological sort on the network to be mapped, whereby the network is represented in form of a Directed Acyclic Graph. The system locates feasible reconvergent paths existing from transitive fan-ins of each node using a Reconvergent Path Locator for replicating fan-outs of the nodes in the DAG, and therefore optimizing the number of LUT's and the time consumed in the mapping process.

Abstract: A transceiver provides a high-speed transmission signal using shared resources and reduced area. A differential amplifier has its current source/sink connected to a supply terminal. A multiplexing circuit is configured to connect an input of the differential amplifier to an I/O pad so as to output a received input/output signal to internal integrated circuit logic during one mode, or alternatively connect an output of the differential amplifier to the I/O pad so as to output a signal received from the internal integrated circuit logic for input/output during another mode. A level translation operation on the signal may be performed with respect to outputting the signal received from the internal integrated circuit logic.

Abstract: An on-chip timing measurement circuit for improving skew measurement and timing parameter characterization in integrated logic circuits providing increased accuracy and range. The measurement circuit includes a chip delay element characterization circuit for determining chip specific delay values having one output connected to a second control input of the programmable delay generator and receiving an output from the programmable delay generator for providing a value corresponding to the measured chip specific delay element timing, the characterization circuit being enabled by a control signal from the analyzer during a setup phase of the measurement cycle thereby enhancing the accuracy of the measurement for both skew measurement and timing parameter characterization.