Abstract: An apparatus for controlling operation of an amplifier device when supply voltage provided to the amplifier device varies at an input voltage supply locus. The amplifier device has an operating parameter varying in generally direct proportion with the supply voltage. The apparatus includes: (a) a reference parameter supply providing a reference parameter; (b) a modeling circuit coupled with the input voltage supply locus that models the amplifier device; (c) a comparing circuit coupled with the modeling circuit and the reference parameter supply that compares a model operating parameter from the modeling circuit and the reference parameter and provides a control signal to the modeling circuit and the amplifier device in response to the comparing; the control signal alters operation of the modeling circuit and the amplifier device to reduce variance between the reference parameter and the model operating parameter from a predetermined relationship.

Abstract: An apparatus for compensating operating current in an amplifier device when supply voltage to the amplifier device decreases below a predetermined value at an input voltage supply locus includes: (a) A first control circuit coupled with the input voltage supply locus. The first control circuit generates an output signal at an output locus when the supply voltage decreases below the predetermined value. (b) A second control circuit coupled with the output locus and coupled with the amplifier device.

Abstract: A driver circuit comprises a driver portion, differential voltage input terminals, feedback circuitry, and differential voltage output terminals. The feedback circuitry connects a sample portion of the driver portion to a mixer portion of the driver portion. The sample portion may comprise an internal connection to the driver portion, for example, at a midpoint between differential outputs by the driver portion before regulation of the same differential voltages.

Abstract: An apparatus for regulating voltage for at least one differential transistor pair having a voltage follower buffer, the voltage follower section having a first voltage-temperature response, includes: (a) a differential amplifier having two input loci and an output locus, a first input locus of the two input loci receiving a reference voltage; (b) a temperature responsive unit coupled between the output locus and ground; and (c) a feedback line coupled between the temperature responsive unit and a second input locus of the two input loci. The temperature responsive unit has a second voltage-temperature response similar to the first voltage-temperature response.

Abstract: A system and method is described for a driver circuit used for high speed data transmission in LVDS and CML transceiver device applications. The transceivers are intended to receive a low voltage differential input signal and interchangeably drive a standard LVDS load with a TIA/EIA-644 compliant LVDS signal, and a standard CML load with a standard CML compatible signal. The driver circuit operates at speeds up to 1.36 Gbps, making it compatible with the OC-24 signaling rate for optical transmission. To accomplish this, the driver uses a mixed combination of voltage and current mode drive sections in the output circuit when coupled to LVDS loads, and when the driver is coupled to CML loads, operates purely in a current mode using only the current mode drive section.

Abstract: An apparatus for effecting high speed switching of a communication signal between a first component and a second component includes: (a) a switching circuit configured for receiving the signal from the first component that includes a plurality of switch elements responding to the signal to produce an interim signal that is substantially a model of the signal; (b) a follower circuit having an input locus coupled with the switching circuit for receiving the interim signal; the follower circuit has an output locus configured for presenting an output signal that is substantially duplicating the interim signal; and (c) a control circuit coupling the follower circuit with the switching circuit and receives a feedback signal from the follower circuit representative of the output signal; the control circuit responds to the feedback signal to effect operation of the switching circuit to control at least one first parameter relating to the interim signal.

Abstract: An apparatus for effecting high speed switching of a communication signal between a first component and a second component includes: (a) a switching circuit configured for receiving the signal from the first component that includes a plurality of switch elements responding to the signal to produce an interim signal that is substantially a model of the signal; (b) a follower circuit having an input locus coupled with the switching circuit for receiving the interim signal; the follower circuit has an output locus configured for presenting an output signal that is substantially duplicating the interim signal; and (c) a control circuit coupling the follower circuit with the switching circuit and receives a feedback signal from the follower circuit representative of the output signal; the control circuit responds to the feedback signal to effect operation of the switching circuit to control at least one first parameter relating to the interim signal.

Abstract: A system and method is described for a driver circuit used for high speed data transmission in LVDS and CML transceiver device applications. The transceivers are intended to receive a low voltage differential input signal and interchangeably drive a standard LVDS load with a TIA/EIA-644 compliant LVDS signal, and a standard CML load with a standard CML compatible signal. The driver circuit operates at speeds up to 1.36 Gbps, making it compatible with the OC-24 signaling rate for optical transmission. To accomplish this, the driver uses a mixed combination of voltage and current mode drive sections in the output circuit when coupled to LVDS loads, and when the driver is coupled to CML loads, operates purely in a current mode using only the current mode drive section.

Abstract: An ablation catheter including a probe, an electrode mounted on the probe so as to be movable relative thereto, a remote-operated actuator means for moving the electrode, an elongate conductor connected to the electrode and insulation provided around the conductor. The insulation can include a sleeve axially slidable on the probe, the elongate conductor extending longitudinally between the probe and the insulation sleeve and the insulation sleeve being retractable at least in part into a recess formed in a rearward portion of the probe.

Abstract: A closure for an opening extending through a tubular member, the opening having a first cylindrical surface of a first internal diameter and a second cylindrical surface of an enlarged internal diameter providing a circumferential ledge, and, in the second cylindrical surface an increased internal diameter circumferential slot, the closure being formed of a cylindrical plug removably positioned within the tubular member and in engagement with the circumferential ledge and including an expandable snap ring having a collapsed and an expanded condition and receivable when in the expanded condition within the circumferential slot to capture the plug between the circumferential ledge and the snap ring. In one embodiment the snap ring is a unitary circumferential member having opposed, spaced apart first and second ends and wherein the snap ring is radially inwardly collapsed by moving the first and second ends towards each other.

Abstract: An ablation catheter including a probe, an electrode mounted on the probe so as to be movable relative thereto, a remote-operated actuator means for moving the electrode, an elongate conductor connected to the electrode and insulation provided around the conductor. The insulation can include a sleeve axially slidable on the probe, the elongate conductor extending longitudinally between the probe and the insulation sleeve and the insulation sleeve being retractable at least in part into a recess formed in a rearward portion of the probe.

Abstract: With reference to the figure, an ablation catheter (1) for use in heart surgery comprises a probe (2), a tubular electrode (3) mounted on the probe, so as to axially be slidable relative thereto, and remote-operated actuator means (4) for so sliding the electrode (3). The probe (2) is of electrically-insulating material, and comprises a tip (6), an axially-extending shaft (7), and a rear end portion (8). A surface groove (9) is formed in the probe which extends longitudinally up to the tip (6). The groove (9) locates a conductor (10) which interconnects the electrode (3) with a controllable source (15) of electrical energy and is enclosed in an insulating sheath (16) of flexible construction. The flexible sheath (16), and conductor (10) therein are axially slidable within the groove (9) of the catheter (1). The sheath (16) provides for electrical insulation of the conductor (10) as the electrode (3) is moved along the probe shaft (7).

Abstract: A side cutter apparatus for an excavating machine having a plurality of spaced rotating digging wheels mounted on a common horizontal shaft, each wheel having a pair of spaced sidewalls, and having frame rails partially extending into the spaces between adjacent wheels; which includes a base plate affixed to the periphery of a cut-away section of a sidewall adjacent to the open space between the wheels; a pivotal side cutter including a back panel disposed in the cut-away section and pivotally mounted at its lower end on the base plate so as to pivot into the open space, a front panel disposed essentially parallel to the back panel and pivotally mounted at its lower end on a common axis with the back panel so as to be pivotally movable therewith, a cutting tooth affixed to the upper portion of the front panel and extending into the open space, a roller rotatably mounted on an axis perpendicular to the front panel and extending through the same into a vertical space between the panels wherein the roller is dir