Abstract: A semiconductor integrated circuit system having a function of automatically adjusting an output resistance value with reference to a temperature of an LSI which is operating. When a count value obtained from a counter by counting the output of a timer becomes equal to a predetermined value, a temperature sensor measures temperatures of LSIs. If a temperature fluctuation measured from a previous measured value is greater than a predetermined width, then a control apparatus issues an output resistance value adjustment request signal to output resistance adjustment units of the LSIs.

Abstract: A circuit for selectively generating one of three voltage level as an output has a pull-up transistor and a pull-down transistor. The circuit includes a bias voltage source for generating a constant voltage signal; a temperature compensating constant-current source for outputting variable voltage signal corresponding to a temperature change; a tri-state control circuit for receiving a data signal to generate a control signal based on the data signal; and a switching circuit, in response to the control signal, for selectively the bias voltage source and the temperature compensating constant current source to the pull-up and pull-down transistors.

Abstract: A driver circuit for driving a load connected between an output terminal and a reference potential, includes a first transistor having a collector connected to a first supply potential and an emitter connected to the output terminal. A second transistor has a collector connected to the output terminal and an emitter connected to the reference potential. An emitter-coupled transistor pair has bases to which a symmetrical control signal is applied, one collector which is coupled through a first resistor to the first supply potential and another collector which is coupled through a second resistor with the output terminal. A controllable current source supplies the transistor pair. A control device controls the current source in proportion to a supply voltage occurring between the first supply potential and the reference potential.

Abstract: This invention provides a circuit and method to replace the passive resistive or statically biased active load devices with dynamically biased active load devices. This allows the load devices to present an effective load which varies depending on the state of the circuit output. The effective load and the time rate of change of the effective load can be dynamically optimized to improve circuit performance with changing conditions. The effective load is varied according to the state of the circuit by the use of time-delayed negative feedback. The biasing of the load devices is also capable to control the logic swing of the circuit. A bias generating circuit employing a dynamically biased active load is described. This provides a method for a family of logic circuits, especially CML circuits, to operate at low voltage and low power at high switching speeds, having symmetrical rise and fall times and well defined logic signal swings.

Abstract: Temperatures on a chip, including particular regions of a chip are monitored by sensing changes in sub-threshold conduction of a field effect transistor (FET) integrated on the chip due to changes in charge carrier population distribution with temperature therein. Such changes in sub-threshold current with temperature are preferably detected using a current mirror and two FETs with different channel geometry and slightly different gate voltages such that the currents are equal at a specific design temperature. The slightly different gate voltages are conveniently provided by a low current voltage divider with or without on-chip voltage regulation in which resistor ratios can be accurately and repeatably obtained. Variations from that temperature thus yield large current differences and substantial signal swing which improve noise immunity. Hysteresis can be applied to the output (or amplified output) of the current mirror to obtain bistable thermostat-like action.

Abstract: A method and an apparatus for controlling compensated buffer circuits. In one embodiment, a compensation buffer control circuit includes a compensation unit with a compensation signal memory location such as a compensation register. The compensation unit is configured to produce a local compensation control signal to control a compensated buffer circuit. The compensation signal memory location is configured to selectively receive and store and the local compensation control signal generated by the compensation unit. The contents of the compensation signal memory location may be read, which allows for the external reading of the local compensation signal generated by the compensation unit. In addition, an external write of an external compensation control signal may be performed to the compensation signal memory location such that the output of the compensation unit can be overridden.

Abstract: A memory device includes a plurality of PMOS transistors and a voltage regulator circuit. Each transistor has a gate, a source region, a drain region, and a well containing the source and drain regions. Each transistor is characterized by a threshold voltage which is dependent on temperature and on a body-source bias voltage. Each transistor is also characterized by a sub-threshold current which is dependent on the transistor's threshold voltage. The voltage regulator circuit is operatively coupled to each well to provide the body-source bias voltage to each well. The voltage regulator circuit temperature-compensates the body-source bias voltage to maintain the threshold voltage of each transistor approximately constant despite changes in temperature. The memory device thus advantageously has a relatively constant stand-by current despite temperature variations.

Abstract: An output buffer includes inverting units which output a level of signal according to a power voltage and temperature. Since the gates of the transistors in the inverting units have threshold voltages which are controlled to operate according to the power voltage and temperature, the gap between the worst and best case conditions of transitional current and speed is reduced, and the performance of a storage device is optimized.

Abstract: A data output drive transistor is rendered conductive when the potential of an internal node attains an H level, whereby an output node is discharged to the level of ground potential. When the drive transistor is turned on, the output node is discharged to the level of ground potential at high speed. This drive transistor is turned on for a predetermined time period when output of a high level data is completed, whereby the output node is discharged to the level of the ground potential for a predetermined time period. As a result, the potential of the output node is lowered from a high level to an intermediate level, so that the amplitude of a subsequent output signal is reduced. An output circuit that can effectively prevent generation of ringing with no increase in the access time is provided. A countermeasure is provided to suppress a ringing at output node which drives the output node at high speed when the output node potential attains a potential at which no ringing is caused.

Abstract: The invention provides a logic circuit including (a) a load element having ends one of which is electrically connected to a first terminal of a voltage source, and the other to an output terminal, (b) a first enhancement mode FET including a drain electrode electrically connected to the output terminal, a gate electrode connected to an input terminal, and a source electrode connected to a junction, (c) a second enhancement mode FET including a drain electrode electrically connected to the first terminal, a gate electrode connected to the output terminal, and a source electrode connected to the junction, and (d) a depletion mode FET including a drain electrode electrically connected to the junction, a gate electrode connected to a control terminal, and a source electrode connected to a second terminal of the voltage source. The logic circuit ensures sufficient noise margin to temperature variation, resulting in a lower supply voltage.

Abstract: When high frequency signals are transmitted to an integrated circuit through a lfine, the line must have a matched terminal resistance located as closely as possible to its end. Every portion of the line without a matched terminal resistance, and each branch of the line, produces disturbing signal reflections. In modern housings of large-scale integrated circuits the terminals are only separated by 0.5 mm, and it becomes increasingly more difficult to connect a resistance as closely as possible to the terminal of the integrated circuit. According to the invention, a field effect transistor (T.sub.R), which functions as a terminal resistance, is located inside the integrated circuit. The value determined by the channel resistance is adjusted by means of a regulated control voltage, so that the effects of operating temperature, changes in the supply voltage and deviations in the integrated circuit caused by manufacturing processes have no effect on the resistance value needed for the line match.

Abstract: A method and apparatus that controls and modulates the amount of hysteresis in a buffer in response to changes in operating conditions. The buffer comprises a first stage switching element and a hysteresis control element. The first stage switching element is configured to have a DC voltage trip point. As an input voltage, transitioning from a first state to a second state, is applied to the first stage switching element, the first stage switching element transitions as the input voltage reaches the DC voltage trip point. The transition of the first stage switching element enables the hysteresis control element to provide a feedback path biasing the first stage switching element. Consequently, as the input voltage transitions from the second logic level to the first logic level, the first stage switching element transitions at a voltage level offset from the DC trip point to provide hysteresis in the buffer.

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: An output buffer with a slew rate that is load independent is comprised of an output buffer (14) that is connected to an output terminal (12). The output buffer (14) is controlled such that it can drive a load (18) with different drive levels by changing the transconductance internal thereto. The transition on the input to the buffer (14) is passed through an intrinsic delay block (34) and variable delay block (40) to provide a delay signal on a node (42). A first phase detector latch (50) with a first threshold voltage compares this transition with the transition on the output terminal (12). A second phase detector latch (60) with a second threshold voltage, also compares this delayed transition with that on the output terminal (12). If both of the latches (50) and (60) indicate that the delayed transition occurred after the transition on the output terminal (12), a control signal on a line (78) is changed by incrementing a counter (74). This will increase the drive to a load (18).

Abstract: A memory device includes a plurality of PMOS transistors and a voltage regulator circuit. Each transistor has a gate, a source region, a drain region, and a well containing the source and drain regions. Each transistor is characterized by a threshold voltage which is dependent on temperature and on a body-source bias voltage. Each transistor is also characterized by a sub-threshold current which is dependent on the transistor's threshold voltage. The voltage regulator circuit is operatively coupled to each well to provide the body-source bias voltage to each well. The voltage regulator circuit temperature-compensates the body-source bias voltage to maintain the threshold voltage of each transistor approximately constant despite changes in temperature. The memory device thus advantageously has a relatively constant stand-by current despite temperature variations.

Abstract: A low capacitance impedance emulator suitable for active conductor termination. The impedance emulator includes an emulating FET and a control circuit coupled to the gate of the emulating FET for maintaining the FET in a linear region of operation. The control circuit includes a control FET, an impedance setting resistor, and an amplifier. The control FET is driven in a closed-loop fashion so that the impedance of the control FET has a known relationship with respect to that of the resistor. The output of the amplifier controls the conduction of both the emulating and control FETs so that the emulating FET provides an impedance proportional to that of the control FET and thus, related to the impedance of the resistor. A disconnect feature is provided, whereby the impedance emulator is responsive to a disconnect signal for disconnecting the impedance provided by the emulating FET.

Abstract: A voltage detector for determining the high or low status of a power supply output voltage, including a front-end detector and an inverting amplifier. The front-end detector includes a number of NMOS and PMOS transistors which constitute active loads. The voltage detector is inherently independent of device fabrication condition changes, as well as on the temperature variations.

Abstract: A CMOS inverter circuit is provided which includes a compensation circuit which modifies the inverter threshold depending on changes in supply voltage and/or temperature. The inverter includes a standard CMOS inverter, current boosting circuitry and a reference signal generator. The input of the inverter is coupled to the current boosting circuitry. A reference signal is also coupled to the current boosting circuitry in order to change the effective PMOS to NMOS ratio of the inverter to control the input threshold over a range of supply voltages and/or temperatures. The reference signal generator generates a reference signal which is dependent upon changes in supply voltage and which can be controlled over a range of temperatures.

Abstract: A digital LSI chip comprises the principal element of a printer controller. On the chip are output transistors for driving connection pads and external loads connected thereto. The chip performance is influenced by variations in the manufacturing Process, supply Voltage, and Temperature (PVT). All of these influence the time delay and risetime characteristics of the output transistors, as does varying the gain of predrivers supplying drive signals for the output transistors. To minimize the influence of PVT variables on these characteristics, a table of predrive gain needed to compensate the effect of PVT variables is generated for several points over the PVT range. Likewise, the frequency of a ring oscillator sensor is tabulated over the same points. These data are paired and stored in a memory. At startup and other times, a microprocessor determines the sensor frequency, accesses the table and sets appropriate predriver gains, thereby maintaining the output transistor characteristics nominally constant.

Abstract: A method for operating a digital logic semiconductor component, wherein: the logic semiconductor component is operated in several operational modes at respective fixed clock cycles depending on environmental temperatures; each operational mode is allocated a respective clock cycle with, in each case, a different clock frequency; each operational mode is allocated a respective temperature-dependent limit value with, in each case, a different limit temperature which when reached causes a change of operational mode to occur; and, when changing to an operational mode with a higher limit temperature, the clock frequency is reduced, and when changing to an operational mode with a lower limit temperature, the clock frequency is increased.

Abstract: A driver for providing binary signals from a data system to a transmission line is disclosed. The driver includes a first field-effect transistor (FET) coupled between an output node and ground for conducting current from the output node to ground. The output node is connectable to the transmission line. An initial charging stage provides an initial charging current to the gate of the first FET for a period of time not to exceed an initial charging time period. The initial charging time period has a length approximately equal to a period of time necessary to increase the gate voltage of the first FET from ground to the threshold voltage of the first FET. A main charging stage provides a main charging current to the gate of the first FET for a period of time not to exceed a main charging time period. A discharging stage provides a discharging current from the gate of the first FET to ground.

Abstract: A translator circuit for converting from a first logic-level range to a second logic-level range, as is generally involved in the translation from an ECL stage to a CMOS stage. The translator includes a reference stage that provides a reference voltage that is coupled to the CMOS logic stage as well as the ECL logic stage. The ECL logic stage is indirectly coupled between a high potential power rail and a low potential power rail through a plurality of transistors. The CMOS stage is coupled to the ECL stage through two emitter-follower transistors. The CMOS stage uses current-mirroring techniques in combination with the isolated reference stage to effect a translation from the ECL logic level to the CMOS logic level. The CMOS stage also provides relatively fast propagation time which may be set, within certain limits, to a desired time.

Abstract: A driver for providing binary signals from a data system to a transmission line is disclosed. The driver includes a first field-effect transistor (FET) coupled between an output node and ground for conducting current from the output node to ground. The output node is connectable to the transmission line. A first input stage conducts current from a first voltage supply to the gate of the first FET. The first input stage includes a voltage sensing amplifier for comparing a reference voltage to the voltage potential of the output node and for controlling the amount of current conducted to the gate of the first FET in response to the comparison. A second input stage conducts current from the gate of the first FET to ground.

Abstract: A high speed multiple input NOR gate. In an illustrative embodiment, the invention includes a plurality of pull-down transistors for providing an output signal. A pull-up transistor is coupled to the plurality of pull-down transistors for providing a drive current. A regulator is coupled to the pull-up transistor for regulating the drive current in response to temperature and power supply voltage variation so as to maintain the speed of the output signal during a low-to-high transition of the output signal. In specific implementations, the NOR gate is designed to regulate the output signal so that a high level or a low level thereof is maintained at a predetermined level.

Abstract: Voltage translator apparatus to translate TTL or CMOS logic level inputs to 0/-5 V logic levels that is insensitive to temperative and bias supply variation. A unique circuit structure comprises a level shift stage employing transistors configured to level shift a source of operating potential to a controlling potential to be applied to a predriver stage. The controlling potential is a function of the input logic levels. The predriver stage drives an output stage capable of providing complementary 0/-5 V logic outputs. The configuration is such as to afford low power consumption as well as proper operation over wide bias supply and temperature ranges.

Abstract: A temperature compensation circuit (54 and 56, FIG. 3 ) is disclosed for maintaining the voltage at a first node. The amount of time the voltage at the first node is maintained is dependent upon the temperature of a temperature sensitive element (96). The circuit comprises a bleed-off transistor (86) and at least one temperature sensitive element (97). The first terminal (90) of the bleed-off transistor (86) is coupled to the first node and the second terminal (88) is coupled to a first voltage level. The control electrode (92) of the bleed-off transistor (86) is coupled to the first terminal (94) of the temperature sensitive element (96). The other pole of the element is coupled to a second voltage level. The element is operable to generate a voltage drop across its poles dependent upon its temperature.