Abstract: A power supply circuit relating to the present invention comprises a differential amplifier for feeding out a voltage as a control voltage in accordance with a difference between a feedback voltage commensurate with an output voltage and a reference voltage, an output current control element for feeding out an output current in accordance with the control voltage fed thereto from the differential amplifier, an output line by way of which the output current is supplied to a load, a feedback line by way of which a voltage on the output line is fed back as the feedback voltage to the differential amplifier, the feedback line connected to the output line, and a clamping circuit for maintaining the control voltage so as not drop below a predetermined value.

Abstract: An fully integrated DC-to-DC switching converter having an inductor, where the inductor has magnetic material that may be amorphous CoZrTa, CoFeHfO, CoAlO, FeSiO, CoFeAlO, CoNbTa, CoZr, and other amorphous cobalt alloys. The magnetic material allows for a relatively high switching frequency. In one embodiment, the inductor has two sub-structures, where each of the two sub-structures are parallel to each other and each includes a conductor having upper and lower portions. The conductors of the two sub-structures are electrically connected to each other, and the upper and lower portions are arranged so that magnetic flux from one of the sub-structures couples with the magnetic flux from the other sub-structure so as to provide a relatively high inductance with small form factor. In another embodiment, the inductor is a simple conductor surrounded by high-frequency magnetic material. In both structures, oxide insulates the conductors from the magnetic material.

Abstract: A high-frequency switch circuit is presented. The invention includes a pair of switches, a pair of inductors, and a pair of diodes. Inductors are electrically connected in series between the switches which are thereafter electrically coupled to a power source. Switches are electrically connected to gate drivers so as to control and coordinate the cycling of switches between ON and OFF states. Inductors are also electrically connected to an output thereby communicating a voltage waveform thereto. In some embodiments, it may be desired to electrically connect the inductors to an output circuit to further modify the waveform. Diodes are likewise electrically connected about the switches and inductors. The present invention is applicable to a variety of circuits having a totem pole arrangement of switches sequentially cycled ON and OFF, examples including but not limited to half-bridge, full-bridge, and hybrid configurations.

Abstract: A DC to DC converter to convert an input voltage to an output voltage. The DC to DC converter may include a pair of switches including a high side switch and a low side switch, an inductor coupled to the pair of switches; and a controller. The controller may be configured to estimate a zero crossing of an inductor current through the inductor without directly measuring said inductor current. An associated method is also provided.

Abstract: A pulse width modulation system for use in a switching power supply circuit provides high-resolution pulse width modulated signals. The pulse width modulation system is configured to receive a control signal comprising a (m+n)-bit binary word and to provide a pulse width modulated signal with a predetermined average duty cycle having a resolution of substantially 2?(m+n). The pulse width modulation system includes a timing circuit for providing 2m timing signals, a dithering circuit, and a signal generator. Upon receiving the control signal, the dithering circuit is configured to provide a modified control signal, which comprises a series of up to 2nm-bit binary words. The signal generator is configured to receive the timing signals and the modified control signal and to provide the pulse width modulated signal having a duty cycle, which, when averaged over 2n timing cycles, is approximately equal to the predetermined average duty cycle.

Abstract: A motor driving apparatus which includes a pair of field-effect transistors connected in series between a first supply voltage and a second supply voltage lower than the first supply voltage, an output smoothing circuit connected to a node between the two field-effect transistors, a driver for controlling on/off states of the field-effect transistors according to an input signal, and a detector for detecting on/off states of body diodes attached respectively to the field-effect transistors. Only after either of the body diodes is detected being on are the field-effect transistors respectively turned on to produce an output corresponding to the input signal so as to eventually produce a desired output voltage from the first supply voltage.

Abstract: A high efficiency power converter comprises a boost converter for converting an input voltage to a first voltage on a first output, a buck converter for converting the input voltage to a second voltage on a second output, a linear regulator for converting the first voltage to a third voltage on the second output when the second voltage is lower than a first threshold, and a voltage detector for detecting the input voltage for preventing a reverse current flowing from the second output to the buck converter when the input voltage is lower than a second threshold.

Abstract: A high voltage regulator including a current mirror including a pair of transistors, one of the transistors being connected to a node that outputs an output voltage Vout, a diode stack that includes a plurality of serially connected transistors T0, T1, T2, . . .

Abstract: A constant voltage circuit is disclosed that includes a constant voltage generator circuit part converting an input voltage into a predetermined constant voltage in accordance with an externally input control signal and outputting the constant voltage; a first capacitor connected to the output end of the constant voltage generator circuit part; a second capacitor charging the first capacitor; and a switch circuit part controlling charging and discharging of the second capacitor in accordance with the control signal. The switch circuit part charges the second capacitor and blocks the discharging of the second capacitor to the first capacitor when the constant voltage generator circuit part is caused to stop outputting the constant voltage by the control signal, and stops applying the input voltage to the second capacitor and charges the first capacitor when the constant voltage generator circuit part is caused to start outputting the constant voltage by the control signal.

Abstract: Methods and structure for improved high-speed TDF testing using an on-chip PLL and associated logic to generate high speed launch and capture pulses. A reference clock may be applied to a PLL circuit within the integrated circuit under test to generate a higher frequency PLL Clock. Gating Logic features and aspects within the integrated circuit may apply the PLL Clock signal to a TDF Clock signal when so directed by a TDF Enable signal from an external test system. The PLL Clock is applied to the TDF Clock signal path for precisely two clock pulses for use as a launch and capture pulse sequence for TDF testing at higher speeds than the external automated test system may achieve.

Abstract: An actuator for pressing a plurality of circuit contacts carried on a microcircuit package against a plurality of test contacts has a frame having a top surface and a bottom surface facing away from the top surface. The frame has first and second end slots each intersecting the top surface at opposite ends thereof. A loader foot is carried by the frame's bottom surface for applying force to a microcircuit. First and second latch elements, each respectively mounted within the frame's first and second end slots are each shiftable between a latched position and an unlatched position within the frame's first and second slots, each said latch element when in the latched position for gripping an edge of an alignment plate and when in the unlatched position for releasing the alignment plate. An actuator element mounted on the frame's top surface receives manual force and converts the received manual force to force applied to the latch elements to shift the latch elements between the latched and unlatched positions.

Abstract: A piston velocity detector to determine the velocity of a magnet carrying piston in a cylinder, preferably in the form of a self-contained, hand-held, battery powered piston velocity detector including a plurality of magnet field sensors disposed in an array fixedly spaced from each other within the detector.

Abstract: The rotation angle-detecting device has a main rotator and two detecting rotators that rotate as the main rotator rotates. Each of the two detecting rotators has a magnet and a magnetic detector. As the detecting rotator rotates, a change occurs in magnetic lines of force from the magnet. From the change, the magnetic detector detects rotation of the detecting rotator. According to the rotation detected, the device determines the rotation angle of the main rotator. In addition, a ring-shaped ferromagnetic body is disposed around the magnet or the magnetic detector of the detecting rotator. The structure described above enables magnetic detection without disturbance in each magnetic field of the magnets, and even in a downsized structure, the device can detect the rotation angle with high accuracy.

Abstract: A rotation sensor has a sensor and a processing circuit that are provided as an integrated circuit chip (IC chip). The sensor has a magnetic resistance element. The rotation sensor senses an angular change of a magnetic vector as a change of resistance. The rotation sensor is located to face a rotor, or a helical gear used in an automatic transmission. The magnetic resistance element is located such that a sensing plane thereof is parallel to a hypothetical plane perpendicular to the line of inclination of each tooth of the rotor.

Abstract: Apparatus (10) for establishing the positions of metal objects in a mixed input stream of both metal and non-metal objects, the apparatus comprising a differential metal-detecting coil (14A) having a first coil portion wound in a first sense and a second coil portion of generally similar shape and size to the first, wound in a second sense opposite to the first sense, and conveying means (11) for moving objects with respect to, and past, the differential metal-detecting coil in a plane and in a direction with unit vector â, characterised in that the second coil portion is displaced from the first coil portion by a displacement B having a component in the plane in a direction with unit vector {circumflex over (b)}, wherein 0 < cos - 1 ? a ^ · b ^ < ? 2 , and in that the apparatus further comprises analysing means for analysing the form of the output voltage of the coil as a function of time to establish the position of said metal objects in a direction ? in the plane, where ? is d

Abstract: Errors in qualitative phase contrast measurements due to gradient field heterogeneities are reduced by using either a generalized reconstruction algorithm or an approximate reconstruction algorithm. True velocities are calculated using measured velocity information and phase differences, first moments of gradients, and gyromagnetic ratio.

Abstract: The subject invention pertains to a method for acquiring and reconstructing a collection of time crucial magnetic resonance images. The subject invention is applicable for speeding up acquisition of or improving the quality of the set of images. In one specific embodiment, the subject method is used to reduce the time required to generate a cardiac CINE sequence of phases of the heart.

Abstract: An object of the present invention is to provide a method of controlling and observing binding of sample substances in an aqueous solution. An apparatus of the present invention has a unit applying a strong magnetic field to a sample and an oscillator applying an electromagnetic wave in a THz field onto the sample. A probe and an observing unit which can bring about nuclear magnetic resonance in the sample and detect it are arranged. An electric signal is sent to a THz-ray oscillator to apply an electromagnetic wave having a resonance frequency of unpaired electron spin of the sample onto the sample. An electric characteristic of the nuclear magnetic resonance is detected to observe a binding change in the sample.

Abstract: Metabolite images are produced with an MRI system using a priori information about the resonant peaks of the metabolites and their relative sizes to reduce the amount of NMR data needed for proper spectral resolution. With the a priori information the acquired NMR signal is modeled. Using this model and NMR data acquired at a plurality of echo times (TE), the metabolite at each image pixel is calculated.

Abstract: In a K-space SENSitivity Encoding (KSENSE) magnetic resonance parallel imaging method the sensitivity distribution of MR reception coils; is calculated and based on the sensitivity of the coils, signals from the respective coil merging channels are merged. The merged data are used to perform k-space data fitting and optimal fitting parameters are found. The fitting parameters are used to remove artifacts in the reconstructed image.

Abstract: The reversible transverse susceptibility of magnetic nanoparticles is used to achieve magnetic flux amplification in magnetic resonance settings. Nanoparticles having substantially uniaxial or unidirectional magnetic anisotropy and a reversible transverse susceptibility in the presence of the high DC magnetic field provide either or both of an amplification of the generated signal of an inductive coil or the detected signal of an inductive coil.

Abstract: A microstrip-based RF coil for use in an MRI apparatus constructed to perform human head imaging is provided and includes (a) a cylindrical non-magnetic core module having an outer surface and a longitudinal axis, a cylindrical bore extending through the core module along the longitudinal axis and defining an inner surface; and a plurality of conductive strip lines. The strip lines extend parallel to the longitudinal axis on the outer surface of the core module. The coil is constructed such that one or more of the conductive strips are divided into conductive microstrip segments with one or more tuning capacitors being bridged between two adjacent microstrip segmented sections of the conductive strip. The coil also include a shield support cylinder that is disposed concentrically about the core module and is spaced therefrom to receive the tuning capacitors.

Abstract: A system for detecting or determining the nature of a subterranean reservoir. An electromagnetic field is applied using a dipole antenna transmitter and this is detected using a dipole antenna receiver. The measurements are taken with the antenna both in-line and parallel and the difference between the two sets of measurements is exploited. A characteristic difference indicates a high resistive layer, which corresponds to a hydrocarbon reservoir.

Abstract: A method is described for characterizing a subsurface formation with a logging instrument disposed in a borehole penetrating the formation. The logging instrument is equipped with at least a transmitter system and a receiver system. The method entails positioning the logging instrument within the borehole so that the transmitter system and receiver system are disposed in the vicinity of a formation boundary of interest and measuring the azimuthal orientation of the logging instrument. Electromagnetic energy is transmitted into the formation using the transmitter system and signals associated with the transmitted electromagnetic energy are measured using the receiver system. The method further entails determining the relative azimuth of the formation boundary, composing a symmetrized directional measurement using the measured signals and the determined relative boundary azimuth, and determining the relative dip of the formation boundary using the composed directional measurement.

Abstract: A method is disclosed for determining spatial distribution of resistivity of Earth formations surrounding a wellbore having a conductive pipe therein. The method includes measuring resistivity of the Earth formations using measurements of current leakage along the pipe at selected axial positions. Electromagnetic properties of the Earth formations are measured from within the pipe. The measurements of electromagnetic properties correspond to a larger axial distance and to a greater lateral distance than the measurements of resistivity from current leakage. The current leakage and electromagnetic measurements are jointly inverted to obtain a model of the spatial distribution.

Abstract: A RF current transformer sensor includes a first sensor portion and a second sensor portion. The first and second sensor portions are configured to define a fixed opening for receiving a test object. The RF current transformer sensor is capable of detecting current pulses between the first sensor portion and the second sensor portion for sensing partial discharges from the test object. Further disclosed is a method of partial discharge sensing.

Abstract: A microwave integrated circuit chip having microwave transmission line coupled to an input of a microwave circuitry: The microwave transmission line comprises: a substrate; a strip conductor disposed on a first surface of the substrate, such strip conductor having an input signal pad at one end thereof, and a ground plane disposed on a second, opposite surface of the substrate. The microwave circuitry has capacitive input impedance. The chip includes a via passing from the first surface of the substrate, through the substrate, to the ground plane. A test probe ground pad is disposed on the first surface of the substrate and spaced from a portion of the via disposed on the first surface of the substrate.

Abstract: A capacitance sensor of the present invention is equipped with a sensor unit that comprises a pair of detection electrodes, which are connected to respective reference capacitors, are provided with being oppositely separated, and can contact each other; and an insulation member having flexibility by holding at least one detection electrode. And a capacitance type object detection method thereof is an object detection method for detecting an object's nearing: when the object nears, a non-contact sensor detects it with non contact according to a change of a capacitance; and when the object makes contact, a contact sensor, which deforms by the contact of the object, detects it with contact.

Abstract: A toner current measuring device able to measure a toner current. The toner current measuring device having provided therein a toner deposit capacitor c1 including an electrode 11 and an electrode 12 disposed in opposition, a reference capacitor c2 having a mechanism for adjusting a capacitance thereof; a power supply unit 4; and a measuring unit 10 for measuring, when a voltage is applied to both capacitors to cause a transfer, between the opposing electrodes, of charged toner deposited on the electrode 11, a difference between currents flowing in the toner deposit capacitor c1 and the reference capacitor c2, the difference being measured as a toner current generated as a result of the transfer of the charged toner.

Abstract: A circuit for alternatively controlling a current through a device and permitting measurement of a voltage across the device or controlling a voltage across the device and permitting measurement of a current through the device includes a sense impedance in series combination with the device, an error amplifier selectable to control the controlled current or voltage, the error amplifier providing an error signal for the control, and a floating buffer driving the series combination in response to the error signal.

Abstract: Products and assemblies are provided for socketably receiving elongate interconnection elements, such as spring contact elements, extending from electronic components, such as semiconductor devices. Socket substrates are provided with capture pads for receiving ends of elongate interconnection elements extending from electronic components. Various capture pad configurations are disclosed. Connections to external devices are provided via conductive traces adjacent the surface of the socket substrate. The socket substrate may be supported by a support substrate. In a particularly preferred embodiment the capture pads are formed directly on a primary substrate such as a printed circuit board.

Abstract: A test probe tip constructed substantially from resistive material. The resistive material is made of resistive conducting material substantially enclosed in and dispersed throughout encapsulating material. The test probe has a probing end for probing electronic circuitry and a connection end for interfacing with a probing head. The resistive conducting material forms at least one path through the encapsulating material from the probing end to the connection end. The resistive conducting material may be a plurality of longitudinally extending resistive/conductive members or a plurality of particulate resistive/conductive members.

Abstract: A contactor is provided which contactor comprises an insulating substrate, a concave portion formed in the insulating substrate and extending in a perpendicular direction from a surface thereof, and elastic conductive particles disposed in the concave portion. A part of one of the conductive particles protrudes from the surface of the insulating substrate.

Abstract: A touch probe is provided, including a deflectable stylus with a rest position mechanism on which the stylus is arranged, and a housing in which the rest position mechanism is accommodated. The rest position mechanism includes a stylus holder with carrying elements and seating elements corresponding to the carrying elements that interact with the carrying elements to arrange the stylus holder in the touch probe. The carrying elements and seating elements form a sensing circuit which is closed when the carrying elements are in contact with the seating elements and which is open when one of the carrying elements is not in contact with a corresponding seating element. The carrying elements are provided with electrical contacting means that is formed independently of a clamping device.

Abstract: A testing apparatus, system and method for testing computer memory modules are disclosed. The apparatus includes a motherboard having a processor and at least one resident memory socket fixed to the motherboard. A remote memory socket is provided and located a distance from the resident memory socket, such as on a periphery of the motherboard. The remote memory socket is coupled to the resident memory socket by a conductor assembly such as a ribbon cable and an adapter. A memory module is placed in the remote memory socket and tested using a signal or combination of signals from the processor. A plurality of motherboards, each being configured with remote memory sockets, may be combined to form a testing system suitable for use with an automated handler.

Abstract: An electronic device is moved into a first position with respect to probes for making electrical contact with the device. The electronic device is then moved into a second position in which the electronic device is pressed against the probes, compressing the probes. The movement into the second position includes two components. One component of the movement tends to press the electronic device against the probes, compressing the probes and inducing a stress in the probes. The second movement tends to reduce that stress. Test data are then communicated to and from the electronic device through the probes.

Abstract: The cleaning device may clean probe elements. The probe elements may be the probe elements of a probe card testing apparatus for testing semiconductor wafers or semiconductor dies on a semiconductor wafer or the probe elements of a handling/testing apparatus for testing the leads of a packaged integrated circuit. During the cleaning of the probe elements, the probe card or the handler/tester is cleaned during the normal operation of the testing machine without removing the probe card from the prober. The cleaning device has a working surface with a particular characteristic (a matte finish or a conductive material) so that a prober is capable of automatically determining the location of the working surface of the cleaning device and therefore operate in an automatic cleaning mode.

Abstract: A method and apparatus for a thermal stratification test providing cyclical and steady-state stratified environments. In order to test an electronic device, for example one having one or more levels of ball-grid-array interconnections, e.g., connecting a chip to a flip-chip substrate and connecting the flip-chip substrate to a printed circuit board of a device, an apparatus and method are provided to heat one side of the device while cooling the second side. In some embodiments, the process is then reversed to cool the first side and heat the second. Some embodiments repeat the cycle of heat-cool-heat-cool several times, and then perform functional tests of the electronic circuitry. In some embodiments, the functional tests are performed in one or more thermal-stratification configurations after cycling at more extreme thermal stratification setups. In some embodiments, a test that emphasizes solder creep is employed.

Abstract: A method of testing and an embedded probe-enabling socket are provided for implementing debug and testing functions. The socket includes an integral probe structure enabling Top Side of the Module (TSM) signal probing. The socket includes a substrate with a topside including a plurality of probe pads. A TSM socket frame includes a plurality of probe pins electrically connecting to respective probe pads on the substrate topside. The probe pins are electrically connected with a respective signal to be monitored.

Abstract: A socket electrically coupled to a BGA unit includes a plurality of ball contacts including a housing wherein a through-hole having a larger diameter than that of the ball contact is formed in a surface of the housing, which faces the BGA unit, in order to the through-hole corresponds the plurality of ball contacts and a pin contact provided in a plurality of through-holes and contacting a corresponding side part of the ball contact. More desirably, the plurality of pin contacts is provided in order that each extending directions of the pin contacts are opposite to one another.

Abstract: A base controller disposed in a test cassette receives test data for testing a plurality of electronic devices. The base controller wirelessly transmits the test data to a plurality of wireless test control chips, which write the test data to each of the electronic devices. The wireless test control chips then read response data generated by the electronic devices, and the wireless test control chips wirelessly transmit the response data to the base controller.

Abstract: An output buffer circuit includes a signal path used for testing and designed for outputting output signals at predetermined logic levels in response to internal output signals from an internal logic circuit. The output buffer circuit and includes a first control input, a second control input, a test signal input circuit, and a plurality of output buffers. The first control input receives a predetermined control signal. The second control input receives a test signal having a predetermined voltage. The test signal input circuit switches between a test mode and a normal mode in response to the control signal, receives and outputs the test signal while in the test mode, and receives and outputs the internal output signals while in the normal mode. The plurality of output buffers output the output signals through a plurality of outputs, in response to the internal output signals or the test signal.

Abstract: Disclosed is an apparatus and method for diagnostically testing circuitry within a device. The apparatus and method incorporate the use of energy (e.g., light, heat, magnetic, electric, etc.) applied directly to any location on the device that can affect the electrical activity within the circuitry being tested in order to produce an indicator of a response. A local sensor (e.g., photonic, magnetic, etc.) is positioned at another location on the device where the sensor can detect the indicator of the response within the circuitry. A correlator is configured with response location correlation software and/or circuit tracing software so that when the indicator is detected, the correlator can determine the exact location of a response causing a device failure and/or trace the connectivity of the circuitry, based upon the location of the energy source and the location of the sensor.

Abstract: A laser beam irradiation unit irradiates a laser beam on a top surface pattern portion of a wiring to be inspected among plural wirings formed on a substrate, with an intensity high enough to cause laser abrasion or two-photon absorption at the irradiated portion. A D.C. power supply applies, via an ammeter, a predetermined voltage between an electrode portion that traps electrons released from the top surface portion and a contact prove pressed against a bottom surface pattern of the wiring. An open circuit state and a short-circuit state of the wiring are judged using a current value measured in the ammeter. It is thus possible to inspect a wiring for an open circuit and a short-circuit easily without bringing a probe into contact with the lands of wirings on a top surface of the substrate to be inspected.

Abstract: A non-contact method is described for acquiring the accurate charge-voltage data on miniature test sites of semiconductor wafer wherein the test sites are smaller than 100 ?m times 100 ?m. The method includes recognizing the designated test site, properly aligning it, depositing a prescribed dose of ionic charge on the surface of the test site, and precise measuring of the resulting voltage change on the surface of the test site. The method further compromises measuring of the said voltage change in the dark and/or under strong illumination without interference from the laser beam employed in the Kelvin Force probe measurement of the voltage. The method enables acquiring of charge-voltage data without contacting the measured surface of the wafer and without contaminating the wafer. Thus, the measured wafer can be returned to IC fabrication line for further processing.

Abstract: A semiconductor chip includes a plurality of pads; a plurality of interface circuits connected with the plurality of pads, respectively; an internal circuit connected with the plurality of interface circuits; and a transfer circuit connecting the plurality of interface circuits with each other in response to a test mode signal. One of the plurality of pads is a selected pad when the pad is probed, at least one remaining pad is a non-selected pad, one of the plurality of interface circuits corresponding to the selected pad is a selected interface circuit, and at least one remaining interface circuit is a non-selected interface circuit. The internal circuit is tested by using the selected pad, the selected interface circuit, the transfer circuit, and the non-selected interface circuit without using the non-selected pads.

Abstract: An apparatus, a system, and a method for semiconductor processing automation, specifically for handling, are disclosed herein. In various embodiments, an apparatus for handling comprises a pick-and-place subassembly and a press subassembly.

Abstract: Circuits and methods to sense the current through a coil of an integrated switching converter, applicable to boost and to buck converters, have been achieved. The present invention uses a “replica biasing” technique to avoid a resistor for current measurement. The current through a pass device is mirrored into a replica, having a scale of n and being much smaller in size, of said pass device. The current through the replica is mirrored to another branch of the circuit and back again to achieve a fast stabilization of the current. The current through the replica is mirrored again to an output branch of the circuit, which conducts exactly a fraction 1/n of the current flowing through the pass device. The self-biasing current loop of the invention adapts quickly to the actual current level through the pass device of the switching converter. Accuracies better than 5% are achieved over a wide range of dynamic range.

Abstract: An apparatus and method for inspecting a liquid crystal display device is provided. The apparatus includes: a camera photographing a front surface of a liquid crystal panel; a back light irradiating light to the liquid crystal panel; a diffuser sheet diffusing the light generated from the back light; a prism sheet converting the diffused light so as to be perpendicularly incident to a rear surface of the liquid crystal panel; a probe unit applying an inspection signal to the liquid crystal panel; and a frequency converter converting a frequency of the light generated from the back light. The apparatus for inspecting the liquid crystal display device according to the invention detects bad sub-pixels, impossible to detect with the naked-eye, improving the quality of the liquid crystal display device.

Abstract: A compensation circuit is disclosed. The compensation circuit includes a driver stage having an output, a differential output device including a base coupled to the output of the driver stage, and a feedback block coupled to a first emitter of the differential output device. The differential output device includes a second emitter to provide a differential output, and the feedback block generates a feedback signal to adjust the differential output. The first emitter comprises a replicating transistor, and is proximate to the second emitter of the differential output device. By keeping the replicating emitter near the differential output device, the variances of temperature and process over the semiconductor die do not affect the performance of the compensation circuit. The compensation circuit may also compensate for variations in common-emitter current gain.