Abstract: A buffer circuit (318) including a first half circuit and a second half circuit. Each half circuit includes a first MOS transistor (M4, M9) as the input device and a source follower, a second MOS transistor (M23, M22) as a transconductance amplifier device, and a third MOS transistor (M5, M8) as a folded cascode device. The first half circuit receives a buffer input voltage as the input voltage and the second half circuit receives a reference voltage as the input voltage. The first and second half circuits providing a pair of differential output signals indicative of the buffer input voltage. The buffer circuit has a very low input capacitance where the input capacitance does not vary with the buffer input voltage and other operating conditions, such as fabrication process, temperature and power supply voltage variations.

Abstract: The present invention provides a low swing current mode logic circuit including: a current mode logic block having data inputs and outputs; a pre-charging circuit for pre-charging the outputs; a dynamic current source; an evaluation circuit for evaluating the logic block during an evaluation phase; and, a feedback path arranged between the outputs and the dynamic current source which is responsive to a difference between the outputs. The simplicity of generating the low swing, achieved by the feedback which may be implemented by only two transistors, is in contrast with the complexity introduced by some methods used by other logic styles for achieving low swing.

Abstract: A circuit includes a configurable receiver circuit, a multiplexer or demultiplexer coupled to the configurable receiver circuit, and a configurable driver circuit coupled to the multiplexer or demultiplexer. The configurable receiver circuit generates an internal format signal which is received by the multiplexer or demultiplexer. The configurable driver circuit receives the internal format signal from the multiplexer or demultiplexer.

Abstract: A low power output driver includes one of a regulated reduced voltage source that receives a supply voltage and outputs a regulated reduced voltage that is a lower voltage than the supply voltage. The driver also includes a first driver input that receives a first logic signal, a second driver input that receives a second logic signal, a first driver output that outputs a first output signal and a second driver output that outputs a second output signal. The driver includes first, second, third and fourth n-type metal oxide semiconductor (NMOS) that are cross-connected between the reduced voltage and the first and second driver outputs or ground. When the second input is high, the second NMOS and the third NMOS are gated on, the second driver output is raised to the reduced voltage and the first driver output is pulled down to the internal ground.

Abstract: A circuit for calculating a logical combination of two input operands includes a first input for receiving a first dual rail signal having data values of the first input in a calculation cycle and precharge values in a precharge cycle, a second input for receiving a second dual rail signal having data values of the second input in the calculation cycle and precharge values in the precharge cycle, and an output for outputting a third dual rail signal having result values in the calculation cycle and precharge values in the precharge cycle.

Abstract: A current mode logic (CML)-CMOS converter comprises an input stage that is turned on/off by receiving an input voltage from the outside; a voltage control unit that outputs a constant voltage; a first switching unit that is connected to the input stage and the voltage control unit and is turned on/off by the constant voltage applied from the voltage control unit; and a second switching unit that is connected to the input stage and is turned on/off by a signal applied from the input stage.

Abstract: Receiver circuits using nanotube based switches and logic. Preferably, the circuits are dual-rail (differential). A receiver circuit includes a differential input having a first and second input link, and a differential output having a first and second output link. First, second, third and fourth switching elements each have an input node, an output node, a nanotube channel element, and a control structure disposed in relation to the nanotube channel element to controllably form and unform an electrically conductive channel between said input node and said output node. The receiver circuit can sense small voltage inputs and convert them to larger voltage swings.

Abstract: A drive circuit of a computer system is for driving a mode indicator. The computer system includes a first port and a second port. The mode indicator includes a first receiving end and a second receiving end. The drive circuit includes a first input end connected to the first port, a second input end connected to the second port, a first output end connected to the first receiving end, a second output end connected to the second receiving end, a power supply, a first transistor connected between the first input end and the power supply, and a second transistor connected between the second input end and the power supply. Collectors of the first and second transistors are separately connected to the first and second output ends. The mode indicator is dichromatic and has two LEDs emitting non-matching colored light.

Abstract: An actively compensated CML circuit includes a CML buffer circuit and a bandwidth expansion circuit. The CML buffer circuit includes a first MOS transistor and a second MOS transistor in a differential pair configuration. A first load resistor is coupled to a first MOS transistor drain at a first output terminal and a second load resistor is coupled to a second MOS transistor drain at a second output terminal. The bandwidth expansion circuit is coupled to the CML buffer circuit in a source follower configuration. The bandwidth expansion circuit includes a third MOS transistor and a fourth MOS transistor. A capacitor is coupled across a third MOS transistor source and a fourth MOS transistor source. The fourth MOS transistor and the third MOS transistor generate a high pass function at the first output terminal and the second output terminal.

Abstract: In a differential line receiver circuit having differential amplifier circuit where output rise and fall times are influenced by the ability of internal current sources to charge parasitic capacitances, a feedback circuit is provided to tune those current sources so as to deliver equal rise and fall time on both outputs. According to one embodiment a detector signal is derived from timing errors resulting from such rise and fall time discrepancies by means of a nested CMOS inverter arrangement coupled to an integrating element, and then used to control one or both of said current sources.

Abstract: Programmable logic device integrated circuitry having differential I/O circuitry is provided. The differential I/O circuitry may include output drivers for providing differential digital output data signals across pairs of output lines. A user may program the I/O circuitry to accommodate different high-speed differential I/O signaling standards. The user may also program the I/O circuitry to provide a desired amount of preemphasis to the output data signals.

Abstract: Embodiments of the present invention provide a transmitter of a semiconductor device, which can output signals corresponding to input signals having various common mode levels and amplitudes. The transmitter may include a pre-driver unit, main driver unit, and a control circuit. The pre-driver unit modifies a common mode level and the amplitude of first internal output signals to generate internal output signals in response to driver control signals. The main driver unit modifies the common mode level and the amplitude of the second internal output signals. The control circuit detects the common mode level and the amplitude of a connected circuit. The common mode level and the amplitude of the output signals may then automatically be adjusted to be the same as the common mode level and the amplitude of this connected circuit High speed signal conditioning may be accomplished.

Abstract: A switched capacitor buffer operating by the push-pull method is taught. The buffer may include a pull-up device and a pull-down device. A switched capacitor circuit may be used to control the pull-up device and the pull-down device to achieve accurate push-pull operation. According to some embodiments, the switched capacitor buffer displays an optimal combination of design simplicity, low power consumption and high-frequency response.

Abstract: Embodiments utilize analog sub-threshold circuits to perform Boolean logic and soft-gate logic. These analog circuits may be grouped into configurable logic blocks that are locally asynchronous, but block-level synchronous. The Boolean logic, or function, performed by these blocks may be configured by programming bits. Other embodiments are described and claimed.

Abstract: A method and apparatus for creating high speed logic circuits in a CMOS environment using current steering logic cells with actively-peaked NMOS or PMOS loads and the biasing of these logic cells is disclosed. The logic cells can include, for example, buffers, AND gates, OR gates, flip-flops, and latches. The current steering cells with actively-peaked loads can provide benefits such as reduced power consumption, smaller area, and higher speed performance over conventional devices. This performance boost is preferably achieved using NMOS followers with resistively degenerated gates to create frequency peaked transfer function of current-mode logic cells. These logic cells with actively-peaked loads can advantageously be used in circuits in which relatively good power area and performance are desired for state machine logic, parallel to serial conversions, serial to parallel conversions, and the like.

Abstract: Embodiments of the invention include an integrated circuit including a line driver. The integrated circuit includes a voltage mode driver comprising complementary first and second input voltage drivers, a programmable resistor network and a current mode driver. The programmable resistor network allows the amplitude of the line driver outputs to be controlled based on the particular resistor connections in the programmable resistor network. Also, the differential impedance of the integrated circuit and the common mode impedance of the integrated circuit are based on the resistance values of the resistors in the programmable resistor network.

Abstract: There is provided a CML to CMOS converter comprising two current sources both connected between a first power supply, having a first potential, and a driving node, first and second push-pull drive stages each having a current path connected between a second power supply, having a second potential, and the driving node, and each having a control input for one half of a CML signal and an output node. Each of the two output nodes is connected to the control node of a respective one of the current sources, each current source being connected to decrease the current it supplies to the driving node if the potential of its respective output of the converter moves towards the potential of the first power supply.

Abstract: In a flip-flop circuit where latched complementary signals of first and second output terminals are inverted by complementary first and second input pulses, the conductivity of a first load transistor connected to the first output terminal is controlled by the signal from the second output terminal, and the conductivity of a second load transistor connected to the second output terminal is controlled by the signal from the first output terminal.

Abstract: The present disclosure relates to a differential signaling circuit including differential signaling circuitry having at least one output and one input, that can operate in multiple mode of operations while using a single, low voltage supply source. Two or more switches are included and configured to selectively couple a supply voltage to the output dependent on a mode of operation of the differential signaling circuitry. The circuit also includes a switch control biasing circuit operatively coupled to at least one of the switches and to the output of the differential signaling circuitry. The switch control biasing circuit provides a switch control biasing voltage to control a state of the switch based on a voltage level of the output. Further, a bulk biasing circuit is included and operatively coupled to the switch. The bulk biasing circuit selectively provides a bulk biasing voltage to the switch based on the voltage level of the output.

Abstract: In general, the embodiments introduce a pre-charge state between an idle state (when no data in being transmitted) and an active state (when data is being transmitted). In the pre-charge state, both differential signals are pre-charged to the common mode voltage, which is also the crossover voltage. Similarly, an additional pre-charge state is inserted between the active state and the idle state when the signals transition from active to idle. Because both signals for each bit, including the first and last bits, are being driven from the same voltage level, the quality of the first and last bits are improved to be similar in quality to the middle bits.

Abstract: An amplitude limiting value can be set to an intended value of a designer and the dependence of the amplitude limiting value on the temperature can be avoided.

Abstract: An input circuit (a first transistor pair) that receives complementary input signals is connected to a latch circuit (a second transistor pair) that converts the amplitude of an input signal into second amplitude higher than first amplitude. A current mirror circuit (a third transistor pair) is disposed between the latch circuit and a high-level power supply line. The current mirror circuit makes a source voltage of the second transistors being turned on lower than the source voltage of the second transistors being turned off. The second transistors being turned on are likely to be turned off although the on-current of corresponding first transistors is low. To the contrary, the second transistors being turned off are likely to be turned on. Accordingly, even when a voltage of a high logic level of an input signal is low, the level conversion circuit can surely operate without malfunction.

Abstract: A differential voltage signal (LVDS) driver circuit and/or a Current Mode Logic (CML) driver circuit. The circuit includes two current switches, each coupled to a corresponding input node. In a complementary manner, when a differential signal is applied across the input nodes, one current switch is open, while the other current switch is closed, and vice versa. A current allocation component allocates current between the two input current switches such that, when the first current switch is closed and the second current switch is open, increasing current is allocated through the first current switch and the intervening current path between the current allocation component and the first current switch, and vice versa. The circuit includes complementary pre-emphasis and/or current-aided pre-emphasis mechanisms that boost differential output transmission edges.

Abstract: An AND circuit is provided, which has a first differential pair including a first transistor and a second transistor, to which a first input differential signal is inputted, a second differential pair including a third transistor and a fourth transistor, to which a fixed bias is inputted, a third differential pair including a fifth transistor and a sixth transistor, to which a second input differential signal is inputted, and in which the first differential pair is connected to the fifth transistor and the second differential pair is connected to the sixth transistor, and an output terminal, which is connected to the first or second transistor and outputs an AND signal or a NAND signal of the first and second input differential signals.

Abstract: A method and apparatus for creating high speed logic circuits in a CMOS environment using current steering logic cells with actively-peaked NMOS or PMOS loads and the biasing of these logic cells is disclosed. The logic cells can include, for example, buffers, AND gates, OR gates, flip-flops, and latches. The current steering cells with actively-peaked loads can provide benefits such as reduced power consumption, smaller area, and higher speed performance over conventional devices. This performance boost is preferably achieved using NMOS followers with resistively degenerated gates to create frequency peaked transfer function of current-mode logic cells. These logic cells with actively-peaked loads can advantageously be used in circuits in which relatively good power area and performance are desired for state machine logic, parallel to serial conversions, serial to parallel conversions, and the like.

Abstract: Systems and methods provide current mode logic buffers and interface circuits. As an example, in accordance with an embodiment of the present invention, a CML buffer is disclosed that receives and/or provides multiple signal pairs having different common mode voltages to operate over a wider common mode voltage range.

Abstract: A differential amplifier is configured to receive an input signal whose magnitude is referenced between a reference voltage and a first power supply magnitude. A differential current conducted by the differential amplifier induces current to be conducted by a first current mirror, which in turn induces current to be conducted by a second current mirror. The current conducted by the second current mirror produces an output signal that is referenced between the reference voltage and a second power supply magnitude.

Abstract: A system and method is disclosed for providing a fast turn on bias circuit that permits a fast transition from an idle “power down” state to an active “power up” state in current mode logic (CML) transmitter output circuits. The invention comprises a capacitor coupled to a bias transistor and a charge switch circuit for controlling the operation of the capacitor. The capacitor has a value of capacitance that is equal in magnitude and opposite in sign to the Miller coupling capacitance in the bias transistor. The capacitor compensates for the Miller coupling capacitance within the bias transistor in less than ten nanoseconds. This permits a CML transmitter to more quickly restart the transmission of data after an active state has been initiated.

Abstract: The CML (current mode logic) to CMOS converter with a leakage balancing transistor for jitter reduction includes: a differential input stage; an output stage having a first branch coupled to a first output of the differential input stage and a second branch coupled to a second output of the differential input stage; and a leakage balancing transistor coupled to the first branch of the output stage.

Abstract: A current mode transmitter includes a first sink current path, through which a current flows from an output port according to a first bias voltage, a charge error canceller, which supplies a current from a high power supply voltage to a current control port in response to an input signal and counteracts a variation of a second bias voltage in response to an inverted input signal, which has an opposite polarity to that of the input signal, and the second bias voltage, and a second sink current path, which sinks current supplied from the output port in response to the second bias voltage and the inverted input signal, the second sink current path being controlled by the current control port. The input signal and the inverted input signal are complementary.

Abstract: A data input buffer for use in a semiconductor device, including: a detection unit for receiving a reference voltage signal and an input data signal through a first input terminal and a second input terminal respectively in order to detect a voltage level of the input data signal based on a result of comparing the input data signal with the reference voltage in response to a clock enable signal inputted through a third input terminal; and a noise elimination unit connected between the first input terminal and the third input terminal for eliminating a noise of the reference voltage signal.

Abstract: Circuit for providing drive signal waveforms. The circuit includes a current mode logic (CML) driver that includes a common mode voltage (VCM), an output node and a complementary output node. The circuit also has a level shifting mechanism that is coupled to the CML driver. The level shifting mechanism adjusts the common mode voltage (VCM) by either drawing a level shifting current from the output node and the complementary output node or injecting a level shifting current into the output node and the complementary output node.

Abstract: One embodiment of the present invention provides a proximity I/O switch, which is configured to transfer data between the components in a computer system. This proximity I/O switch is comprised of multiple switch chips, which are coupled together through capacitive coupling. This enables the multiple switch chips to communicate with each other without being constrained by the limitations of conventional non-capacitive communication mechanisms. The multiple switch chips in the proximity I/O switch are also configured to communicate with components in the computer system through conventional non-capacitive communication mechanisms.

Abstract: Comparators outputting offset calibration. A MOS current mode logic (MCML) circuit receives input signals and generates differential logic signals on output terminals thereof, and comprises a calibration unit coupled to the output terminals, calibrating output offsets at the output terminals according to digital calibration codes. An output stage is coupled to the differential logic signals at the output terminals of the MCML circuit to amplify the differential logic signal and generating a comparison resulting signal. By adjusting the digital calibration codes applied to the calibration unit, current on the output terminals can be adjusted, such that output offsets at the output terminals of the MCML circuit 10 can be eliminated.

Abstract: An output buffer circuit drives multiple signal formats. The output buffer circuit reduces duplication of output bond pads on an integrated circuit die. The output buffer circuit reduces a need for including conversion buffers on system boards. A single integrated circuit including the output buffer circuit may meet a variety of applications. The output buffer achieves these results with a programmable output voltage swing and a programmable output common mode voltage. In some embodiments of the present invention, an integrated circuit includes at least one single-ended buffer and at least one differential circuit coupled to a pair of outputs. One of the single-ended buffer and the differential circuit is selectively enabled to provide a signal to the outputs.

Abstract: A programmable, equalizing buffer is provided having feedback transistors used to vary the transfer function of the equalizing buffer, such that a low pass response of a transmission channel is substantially equalized. A zero in the buffer's transfer function is established by a conductive state of transistors caused by signal feedback. Multiple transistors establish increased flexibility for establishing the location of the zero, while a cascade of buffer stages provides a second order transfer function effective to cancel second order channel effects.

Abstract: Embodiments of the present invention perform logical operations utilizing a symmetric logic circuit comprising two logic units. In a symmetric logic circuit, the circuit configuration used to process a first logic input in the first logic unit is the same as the circuit configuration used to process a second logic input in the second logic unit, and the circuit configuration used to process the second logic input in the first logic unit is the same as the circuit configuration used to process the first logic input in the second logic unit. The present invention may be used for logic circuits that perform a variety of logical operations, such as XOR, AND, NAND, OR, or NOR.

Abstract: A semiconductor integrated circuit with stabilized amplitude and offset potential of output signals comprising an output circuit including plural transistors supplied with differential signals, for performing switching operation. A first transistor is connected between a first power supply potential and the output circuit. A second transistor is connected between the output circuit and a second power supply potential. A third transistor is connected to the first power supply potential. A fourth transistor, passes a current proportional to that flowing in the second transistor. A differential amplifier controls gate potentials of the first and third transistors such that a potential at a connection point between a first resistance and a second resistance approaches a predetermined potential.

Abstract: A low power high-speed design for integrated circuits using BiCMOS processes is disclosed. The design uses a first stage including bipolar transistor pairs configured as inputs and drivers for an output. A second CMOS stage is coupled to the first stage in a series-gated configuration and receives clock or data inputs. A third stage is coupled to the second stage and is configured as a current source. The combination results in circuits that can operate at conventional supply voltages of 1.8 volts.

Abstract: Programmable logic device integrated circuitry having differential I/O circuitry is provided. The differential I/O circuitry may include output drivers for providing differential digital output data signals across pairs of output lines. A user may program the I/O circuitry to accommodate different high-speed differential I/O signaling standards. The user may also program the I/O circuitry to provide a desired amount of preemphasis to the output data signals.

Abstract: Driver circuit that generates a drive waveform with a static bit swing and a pre-emphasis bit swing. The driver circuit includes an input (IN) node, a complementary input (INB) node, an output (OUT) node and a complementary output (OUTB) node. The driver circuit includes a fundamental swing determination mechanism (FSDM) that is coupled to the output (OUT) node and a complementary output (OUTB) node. The fundamental swing determination mechanism (FSDM) determines or sets the fundamental swing of the drive waveform by generating a fundamental current. The fundamental swing determination mechanism (FSDM) includes at least one switched resistor circuit. The driver circuit also includes a modulation swing determination mechanism (MSDM) that is coupled to the output (OUT) node and a complementary output (OUTB) node. The modulation swing determination mechanism (MSDM) determines or sets the modulation swing of the drive waveform by generating a modulation current.

Abstract: A semiconductor device having a plurality of cascaded IC's (14, 15, 16), wherein the matching impedance between a signal transmission path (12) connected to an external signal transmission path and an input-side or output-side IC (14, 16) is set at 50 ohms which is equal to the characteristics impedance of the external signal transmission path. The matching impedance between a internal signal transmission path (13) and an input-side or output-side IC or intermediate IC is set at 200 ohms which is higher than the 50 ohms. The semiconductor device reduces the current dissipation and can operate at a higher speed.

Abstract: A circuit topology for high speed low voltage logic circuits is disclosed that reduces the number of levels of stacked active circuit elements from 3 to 2. Circuits providing a variety of logic functions are presented, including a latch, an exclusive OR gate, a combination XOR and latch, a multiplexer and a demultiplexer. Circuits built according to the principles of the invention have been operated at speeds of 40 GHz. The circuit topology can operate at supply voltages as low as 2V (for silicon or silicon-germanium based devices) and provide power saving of 25%–50% or more, depending on the logic function. In some embodiments, circuits comprising single ended or differential inputs can be provided.

Abstract: A CML XOR logic circuit is provided that includes a pair of pull-up transistors, a pair of current source transistors and a logic switch network coupled between the pull-up transistors and the current source transistors. The logic switch network including a plurality of transistors divided into a first branch, a second branch and a third branch. A tail current flows through the first branch, the second branch or the third branch based on at least two input signals to the plurality of transistors.

Abstract: A LVDS output driver has been disclosed. One embodiment of the LVDS output driver includes a number of source followers, each of the source followers including a pull-down transistor having a source, a drain, a gate, and a bulk terminal. The embodiment of the LVDS output driver further includes a number of pull-up transistors, each of the pull-up transistors having a source, a drain, and a gate, wherein the drain of each of the pull-up transistors is coupled to the source of a pull-down transistor of the source followers, to output a number of differential signals via the drains of the pull-up transistors. Other embodiments are described and claimed.

Abstract: The power supply-voltage dependency of a current source current is reduced and the power supply voltage is lowered. The invention includes an emitter-coupled logic circuit 118 and a reference-voltage generating circuit 119 for generating a reference voltage VCSC for controlling a drain current (=current source current ICS) of a constant current-supplying n-type MOS transistor 110. The emitter-coupled logic circuit 118 comprises a current switch made up of a pair of emitter-coupled bipolar transistors 106 and 107, a constant current-supplying n-type MOS transistor 110 that is connected in series with the current switch, and resistor means 108 and 109 connected in series with the bipolar transistors 106 and 107 individually for obtaining an output voltage.

Abstract: A line driver which is especially suitable for wirebound data transmission at high bit rates, comprising several parallel-connected driver stages (3) respectively comprising a first pair of transistors consisting of two transistors (4, 5) which are controlled in a differential manner according to digital data to be transmitted, and a second pair of transistors (4, 5). The transistors belonging to the second pair of transistors (6, 7) are series-connected to a corresponding transistor (4, 5) of the first pair of transistors. The individual driver stages (3) are connected by the transistors (6, 7) of the second pair of transistors in a parallel manner to both the terminals of the line driver. Each driver stage (3) is associated with a control circuit (2) with transfer gates (14, 15), producing the differential control signals (VGA, VGB) for the two transistors (4, 5) of the corresponding first pair of transistors.

Abstract: Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C3MOS) logic with inductive broadbanding fabricated in conventional CMOS process technology. Optimum balance between power consumption and speed for each circuit application is achieved by combining high speed C3MOS logic with inductive broadbanding/C3MOS logic with low power conventional CMOS logic. The combined C3MOS logic with inductive broadbanding/C3MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems.

Abstract: To speed up the operation of a decoder circuit, reduce the power consumption of the decoder circuit and increase the cycle, each circuit such as a buffer, a predecoder and a main decoder in the decoder circuit includes a semiconductor logic circuit in which the number of columns of transistors for pulling down at an output node is small, even if the number of inputs is many and the true and a complementary output signal having approximately the same delay time are acquired and the output pulse length of each circuit in the decoder circuit is reduced. With this arrangement, the operation of the decoder circuit can be sped up, the power consumption can be reduced, the cycles can be increased and, in a semiconductor memory, for example, access time and power consumption can be reduced and the cycles can be increased.

Abstract: A high-speed differential signaling logic gate includes a 1st input transistor, 2nd input transistor, complimentary transistor, current source, a 1st load, and a 2nd load. The 1st input transistor is operably coupled to receive a 1st input logic signal, which may be one phase of a first differential input signal. The 2nd input transistor is coupled in parallel with the 1st input transistor and is further coupled to receive a 2nd input logic signal, which may be one phase of a 2nd differential input signal. The complimentary transistor is operably coupled to the sources of the 1st and 2nd input transistors and to receive a complimentary input signal, which mimics the other phase of the 1st differential logic signal and the 2nd differential logic signal. The current source sinks a fixed current from the 1st and 2nd input transistors and the complimentary transistor. The 1st load is operably coupled to the drains of the 1st and 2nd input transistors to provide a 1st phase of a differential logic output.