Abstract: A step gain amplifier has an amplifier with an input and an output, and a bias circuit connected to the input and to a bias node. A passive feedback circuit using only passive elements connects the output to the input. A control circuit is connected to the bias circuit at the bias node.

Abstract: An amplification arrangement comprises a signal-processing element (SVE) with an integrator element (INT) that is coupled on the input side with a first input (E1) for feeding the input signal and with a second input (E2) for feeding a feedback signal. The signal-processing element (SVE) is designed to set a respective level of the input signal and/or the feedback signal as a function of a control signal. The amplifier arrangement furthermore comprises a pulse modulator (PM) that is designed to generate a pulse signal on a pulse output (POT) as a function of a signal applied on the output (SOT) of the signal-processing element (SVE). An output stage (OST) comprises a switching element (SW) that is designed to connect supply-voltage terminals (V1, V2, GND) to an output terminal (OOT) that is coupled with an amplifier output (AOT) and the second input (E2), and a control unit (CU) for driving the switching element (SW) that is coupled with the pulse output (POT).

Abstract: The invention relates to a digital amplifier for providing a desired electrical output power, the amplifier comprising a power source (100) for generating the electrical output power, the amplifier further comprising: a digital input adapted for receiving a digital input signal (112), the digital input signal (112) representing the desired electrical output power level, a reference power generator (124) for generating an analogue reference power controlled by the digital input signal (112), a power measurement component (142; 128) adapted for measuring the power differential between the electrical output power provided by the power source (100) and the analogue reference power, an analogue-to-digital converter (130) adapted for converting the power differential into a digital power differential value (132), a combiner adapted for providing a combined digital signal (136) by adding the digital power differential value (132) to the digital value input to the reference power generator (124) for generating the an

Abstract: An amplifier generates a tri-level output signal in response to an input signal that is pulse-width modulated. The amplifier is filterless and DC free. A control block supplies a multitude of pulse-width modulated (PWM) signals in response to the received digital input signal. A pair of the PWM signals are applied to the signal generator which in response supplies a third signal to the integrator. The integrator integrates the third signal in accordance with a feedback signal.

Abstract: The invention relates to an amplifier capable of delivering a plurality of output signals, these output signals being controlled by a plurality of input signals. A multiple-input and multiple-output amplifier of the invention comprises a common input terminal, 4 signal input terminals, 4 signal output terminals, a common terminal amplifier, 4 active sub-circuits and a feedback network. Each active sub-circuit has a sub-circuit input terminal connected to one of the signal input terminals, a sub-circuit output terminal connected to one of the signal output terminals and a sub-circuit common terminal. The feedback network has four C terminals and one R terminal. Each of said C terminals of the feedback network is coupled to the sub-circuit common terminal of one of said active sub-circuits. The output terminal of the common terminal amplifier is coupled to said R terminal of the feedback network.

Abstract: A resistive circuit includes a first terminal and a second terminal and polycrystalline first and second resistive segments coupled between the first and second terminals. A third terminal A is coupled to the first resistive segment, and a third terminal B is coupled to the second resistive segment. The third terminal A has a first voltage with respect to the first terminal, and the third terminal B has a second voltage with respect to the second terminal. With this arrangement, the non-linearity of resistance of the first resistive segment at least partially compensates for non-linearity of resistance of the second resistive segment.

Abstract: A reconfigurable network arrangement of resistors and switches is constructed so that it can be coupled to one or more operational amplifiers and selectively programmed so as to set the gain of the resulting amplifier. The configuration of the network arrangement of resistors and switches to include resistors that can be connected in the feedback path in series and in parallel with each other is such as to provide a wider selection of gain settings, without the need to increase the physical area of the switches on a integrated circuit arrangement.

Abstract: A wireless device dynamically controls a power level for each channel in a transmission spectrum. The power level is adjusted based on characteristics of signals received in the adjacent channels which results in the wireless device working at maximum ranges consistent with not causing interference to other users of the spectrum.

Abstract: An automatic gain control circuit configured so that a response time is reduced until a gain converges is disclosed. A variable gain amplifier is configured so that a gain is varied by a first control signal. A detector circuit detects an intensity of an output signal of the variable gain amplifier. A comparator compares an output signal of the detector circuit with a reference signal. An integrator integrates a signal corresponding to an output signal of the comparator, and outputs an integration result to the variable gain amplifier as the first control signal. A loop gain control unit, connected between the comparator and the integrator, is configured so that a loop gain is varied by a second control signal. A level detection unit detects an intensity of an output signal of the integrator and outputs a detection result to the loop gain control unit as the second control signal.

Abstract: Musical distortion circuits are presented, typically for use with electric guitars, other electronic musical instruments or other sources of audio signals. In one embodiment, the musical distortion circuits of the present disclosure include a non-limiting clipping section. In one embodiment, the musical distortion circuits of the present disclosure include a waveshaping section. In some embodiments, the musical distortion circuits additionally include pre- or post-distortion or pre- or post-clipping sections.

Abstract: A method of transmitting or receiving with constrained feedback information. A transmitter transmits a plurality of transmit signals from at least one transmit antenna. The plurality of transmit signals are based on one or more input signals, one or more power gains, and one or more beamformer matrices. The plurality of transmit signals are received as at least one receive signal, at at least one receive antenna of a receiver. The receiver generates the constrained feedback information and transmits the constrained feedback information back to the at least one transmit antenna. The transmitter selects at least one of the power gains and at least one of the beamformer matrices for a subsequent transmission based on the constrained feedback information.

Abstract: A self-configurable amplifier and method of amplification, including an RF signal level detector having an input connected to an RF signal, and an output configured to produce a control signal responsive to a power level of the RF signal. The control signal is supplied to a parametric adjustment circuit that includes an input connected to the control signal, and an output configured to provide a negative feedback responsive to the control signal. The negative feedback is supplied to an RF amplifier that includes an input forming an input of the self-configurable amplifier, an output forming an output of the self-configurable amplifier, and a control port connected to the output of the parametric adjustment circuit, such that one or more parameters of the RF amplifier is responsive to the negative feedback.

Abstract: An amplifier generates a tri-level output signal in response to an input signal that is pulse-width modulated. The amplifier is filterless and DC free. A control block supplies a multitude of pulse-width modulated (PWM) signals in response to the received digital input signal. A pair of the PWM signals are applied to the signal generator which in response supplies a third signal to the integrator. The integrator integrates the third signal in accordance with a feedback signal.

Abstract: A feedback amplifier includes an operational amplifier having an input end and an output end. A first resistor is coupled with the input end of the operational amplifier. A second resistor has a first end coupled with the input end of the operational amplifier and a second end coupled with the output end of the amplifier. A voltage divider has a first end being operably coupled with the output end of the operational amplifier and a second end being analog grounded. In an embodiment, the feedback amplifier further includes a first switch coupled to the first end of the voltage divider and the output end of the operational amplifier, and a second switch coupled to an internal node of the voltage divider. In an embodiment, the feedback amplifier is configured to provide attenuation when the first switch is open and second switch is closed.

Abstract: A resistive circuit includes a first terminal and a second terminal and polycrystalline first and second resistive segments coupled between the first and second terminals. A third terminal A is coupled to the first resistive segment, and a third terminal B is coupled to the second resistive segment. The third terminal A has a first voltage with respect to the first terminal, and the third terminal B has a second voltage with respect to the second terminal. With this arrangement, the non-linearity of resistance of the first resistive segment at least partially compensates for non-linearity of resistance of the second resistive segment.

Abstract: A power amplifier module and corresponding system are disclosed for linearizing the output from a power amplifier. Both a feedback system, containing a compensator and the power amplifier in a feedback loop, and a pre-distortion compensation system injecting pre-distortion signals into or before the feedback system are used to compensate for non-linearities in the overall system. The pre-distortion signals may be mixed with signals from the compensator or may be filtered to take into account the loop compensator transfer function of the feedback loop, mixed with baseband signals and then converted into analog signals that are provided to the feedback loop. In modules containing a tracking power supply, an envelope calculator calculates an RF envelope of the baseband signals, which the pre-distortion system uses in conjunction with the baseband signals to generate the pre-distortion signals mixed with the signals from the compensator.

Abstract: A high frequency signal detection circuit includes an input terminal for a high frequency signal to be detected, a switch transferring the high frequency signal as intermittent ringing signal to a first node in response to a pulse signal whose frequency is lower than that of the high frequency signal, a transistor amplifying the signal at the first node, and outputting to a second node, a bias generator generating a bias voltage by which the transistor is operated in its weak inversion region, a resonant circuit outputting the bias voltage to the first node, and resonating the high frequency signal, a capacitor removing a high frequency component of the signal at the second node; and a judgment circuit judging whether or not the high frequency signal is inputted by detecting the signal at the second node, which has the same frequency as the pulse signal.

Abstract: A current feedback-type operational amplifier comprising multiple input parts and one output part, wherein each of the multiple input parts comprises a first input terminal, a second input terminal, and an output terminal, the signals input from the first input terminal are buffer amplified and output to the second input terminal, and current is output to the output terminal in an amount corresponding to the current that flows to the second input terminal; the output terminal part comprises an input terminal and an output terminal, signals obtained by adding in terms of current the signals of all of the input parts are input to the input terminal, and the signals input to the input terminal are converted to voltage signals, amplified, and output to the output terminal; and one of the above-mentioned input parts is made effective and the other input parts are made ineffective in response to first external signals, the impedance of the first input terminal, the second input terminal, and the output terminal of

Abstract: A resistive circuit includes a first terminal and a second terminal and polycrystalline first and second resistive segments coupled between the first and second terminals. A third terminal A is coupled to the first resistive segment, and a third terminal B is coupled to the second resistive segment. The third terminal A has a first voltage with respect to the first terminal, and the third terminal B has a second voltage with respect to the second terminal. With this arrangement, the non-linearity of resistance of the first resistive segment at least partially compensates for non-linearity of resistance of the second resistive segment.

Abstract: An amplifier generates a tri-level output signal in response to an input signal that is pulse-width modulated. The amplifier is filterless and DC free. The amplifier includes an integrator, a signal generator, comparator, a switch pulse logic block, a driver, and a control block. The control block supplies a multitude of pulse-width modulated (PWM) signals in response to the received digital input signal. A pair of the PWM signals are applied to the signal generator which in response supplies a signal to the integrator. The integrator's output signal is compared to a reference signal by the comparator. The switch pulse logic block receives the output of the comparator and a pair of delayed PWM signals and in response generates a multitude of driver signals applied to the driver. The driver supplies an output signal that is adapted to vary between first, second and third voltages.

Abstract: An amplifier (1) adapted to receive an input signal and to generate an output signal at an amplifier output (7) according to the input signal, the amplifier (1) comprising: a feedback circuit arranged to provide a feedback signal indicative of the output signal; an error signal generating circuit (12, 44) arranged to receive the feedback signal and generate a digital error signal according to the feedback signal; and an output signal generating circuit arranged to generate the output signal and to receive the digital error signal and to adjust the output signal according to the digital error signal; the amplifier (1) further comprising: a fault detection circuit (50) arranged to receive the digital error signal and to determine the presence or absence of a fault condition at the amplifier output (7) according to the digital error signal and to provide a signal (54) indicative of the presence or absence of the fault condition.

Abstract: A current feedback-type operational amplifier comprising multiple input parts and one output part, wherein each of the multiple input parts comprises a first input terminal, a second input terminal, and an output terminal, the signals input from the first input terminal are buffer amplified and output to the second input terminal, and current is output to the output terminal in an amount corresponding to the current that flows to the second input terminal; the output terminal part comprises an input terminal and an output terminal, signals obtained by adding in terms of current the signals of all of the input parts are input to the input terminal, and the signals input to the input terminal are converted to voltage signals, amplified, and output to the output terminal; and one of the above-mentioned input parts is made effective and the other input parts are made ineffective in response to first external signals, the impedance of the first input terminal, the second input terminal, and the output terminal of

Abstract: A front-end circuit suitable for digital multimeters and measurement devices may be configured with strictly capacitive attenuators replacing the resistive attenuators in the AC signal path. An inverting programmable-gain amplifier (PGA) may be built around an operational amplifier (op-amp), with a single resistor for DC feedback providing a 1st-order response for AC coupling. The single resistor may be replaced by a more complex RC network to provide a 2nd-order response. The feedback circuit may also include active components such as additional op-amps, which may assist in shaping the overall response and/or reducing the DC offset at the output of the circuit. The capacitive load presented to the input by the front-end circuit may be minimized to compare to capacitances present in resistive implementations. The circuit would not present a DC load to the input since DC loads are typically the result of a resistive attenuator in the DC signal path.

Abstract: A signal amplifying circuit having a small-scaled circuit arrangement and exhibiting a low power consumption is provided without degrading the detection precision of an electrostatic capacity detecting element. A signal amplifying circuit comprising an AC-coupled amplifier; a voltage generating circuit for generating a DC bias voltage that is a reference of AC coupling; and a conveying means for conveying the bias voltage to the amplifier; wherein a very small voltage signal outputted by an electrostatic capacity detecting element is superimposed, as an AC component, on the bias voltage and then amplified. The signal amplifying circuit having the structure described above is characterized in that it is configured such that the input impedance of the conveying means seen from the electrostatic capacity detecting element is higher than the output impedance of the electrostatic capacity detecting element.

Abstract: The invention concerns an audio power amplifier apparatus capable of providing at low manufacturing cost extremely low non-linear distortion, even lower than ?120 dB, comprising a main power amplifying section (3) the output of which is series connected to a secondary of a coupling transformer T1, in turn connected to the apparatus output (IO4), the apparatus being characterised in that the amplifying section (3) provides an output signal Vma having a negative feed-back loop non-inverting gain, and in that it further comprises a cascade of one or more sections (5, 6), the inputs of which are connected to the output of the input section (1) and to the output of the amplifying section (3), and the output of which is constituted of a secondary winding of the transformer T1, the cascade being capable to very accurately extract the error signal Ve with respect to the amplified signal Vi from the signal at the output of the amplifying section and to provide to its output an exact, but anti-phase, copy thereof in a

Abstract: The present invention, generally speaking, provides for high-efficiency power control of a high-efficiency (e.g., hard-limiting or switch-mode) power amplifier in such a manner as to achieve a desired modulation. In one embodiment, the spread between a maximum frequency of the desired modulation and the operating frequency of a switch-mode DC-DC converter is reduced by following the switch-mode converter with an active linear regulator. The linear regulator is designed so as to control the operating voltage of the power amplifier with sufficient bandwidth to faithfully reproduce the desired amplitude modulation wave-form. The linear regulator is further designed to reject variations on its input voltage even while the output voltage is changed in response to an applied control signal. This rejection will occur even though the variations on the input voltage are of commensurate or even lower frequency than that of the controlled output variation.

Abstract: This invention relates to a low noise amplifier, used in radio frequency integrated circuit design, especially low noise amplifiers for ultra broad-band wireless communication, comprising at least a transistor of the core circuit of a low noise amplifier structure, a transformer that is implemented on the chip, in order to form a dual feedback amplifier, that is, an amplifier structure comprising an inductive feedback and a capacitive feedback, wherein the capacitive feedback is used for the low and medium frequency range, while the inductive feedback is used for the high frequency range. By assembling an amplifier circuit with these two feedback paths, it is possible to provide a broadband and good impedance matching at the signal input end of the circuit.

Abstract: A window comparator compares a level of an output signal with an attack reference level, and outputs an attack signal based upon an attack reference comparison result signal thus obtained, and compares the output signal level with a recovery reference level, and outputs a recovery signal based upon a recovery reference comparison result signal thus obtained. An attack timing signal generating unit outputs an attack timing signal at first predetermined time intervals. A recovery timing signal generating unit outputs a recovery timing signal at second time intervals which are longer than the first predetermined time interval. An action determining circuit generates a gain reduction signal and a gain increase signal. The amplification gain of the variable gain amplifier is reduced or increased based upon the gain reduction signal or the gain increase signal.

Abstract: A transmitter (200) has a compression detector for sensing the level of compression (110) in a signal that is being transmitted. The transmitter also has a radio frequency power amplifier (RFPA) (414) that is supplied by a supply modulator (426). The supply modulator provides a dynamic supply bias to the RFPA to maintain a desired amount of compression in the signal being transmitted. The supply modulator is responsive to a modulation signal (207) created by substantially following the envelope (214) of the signal to be transmitted (212). However, various signal and operational conditions can occur which cause the compression level to deviate (506) from the desired level. To maintain the desired compression level, the compression detector provides an output that is used to adjust the modulation signal from following the envelope of the signal to be transmitted in an unadjusted manner.

Abstract: An amplification device for a small detection signal has an amplification factor that is variable and also high accuracy offset cancellation. A first switching element selectively connects a normal phase input terminal of an operational amplifier either to a reference potential or to an output terminal of a sensor. An inverse phase input terminal is connected to the reference potential. A capacitor is connected to an output terminal of the operational amplifier and to an output buffer, a second switching element is arranged to selectively connect the capacitor to the reference potential. Resistors are selectively short circuited by switching elements to vary the amplification factor of the operational amplifier.

Abstract: Estimating non-linearity of a power amplifier includes receiving signals at a first location. The signals include an input signal, a pre-distorted signal, and an output signal. The output signal exhibits distortion, including a non-linearity effect, with respect to the input signal. The power amplifier is located at a second location remote from the first location. The non-linearity of the power amplifier is estimated in accordance with the signals at the first location using an inverse model. Pre-distortion information is calculated according to the estimated non-linearity using the inverse model. The pre-distortion information is sent to a pre-distorter at the second location, where the pre-distorter can reduce the non-linearity effect using the pre-distortion information.

Abstract: The present invention, generally speaking, provides for high-efficiency power control of a high-efficiency (e.g., hard-limiting or switch-mode) power amplifier in such a manner as to achieve a desired modulation. In one embodiment, the spread between a maximum frequency of the desired modulation and the operating frequency of a switch-mode DC—DC converter is reduced by following the switch-mode converter with an active linear regulator. The linear regulator is designed so as to control the operating voltage of the power amplifier with sufficient bandwidth to faithfully reproduce the desired amplitude modulation wave-form. The linear regulator is further designed to reject variations on its input voltage even while the output voltage is changed in response to an applied control signal. This rejection will occur even though the variations on the input voltage are of commensurate or even lower frequency than that of the controlled output variation.

Abstract: An operational amplifier (op-amp) (200, 800, 900) having at least a first stage and a second stage has a feedback path (825) from the output to the input of a second stage, the feedback path includes a first capacitor (801) and a second capacitor (803) in series connected at a node (815) between the first capacitor and the second capacitor, and a clamping circuit (206) connected between the node and a ground (230) for clamping a voltage at the node in response to a voltage at the output. The impedance of the clamping circuit is high during small amplitude input signals, and is low during large amplitude input signals. During large amplitude input signals, the compensation capacitance of the op-amp does not provide feedback from the output to the input, thereby increasing slew rate. A liquid crystal display panel system (1100) includes the op-amp (900) as a column driver.

Abstract: An amplifier with adjustable (pre)distortion, a predistortion adjustment circuit, systems and networks including such amplifiers and circuits, and methods for adjusting (pre)distortion in an analog amplifier. The amplifier architecture generally includes (a) a predistortion circuit configured to (i) select a value for a predistortion function from a plurality of different predistortion values, and (ii) apply the selected predistortion value to an input signal to generate a predistorted input signal; (b) an amplifier configured to amplify the predistorted input signal and provide an output signal therefrom; and (c) an adjustment circuit configured to adjust selection of the predistortion function value in response to a predetermined parameter value of the amplifier. By adjusting the predistortion function, the amplifier provides an output signal in a linear power range over a range of amplifier parameter values and avoids overcompensation that can occur when the predistortion signal is not adjustable.

Abstract: One aspect of the invention is an amplifier (10), comprising an input stage amplifier (20) coupled to an output node (81). The amplifier (10) further comprises a class D output stage (50), which comprises at least two switching elements (P1, N1) and coupled to the output node (81). The amplifier (10) also comprises a control circuit (40) coupled to the output stage (50). The control circuit (40) is operable to produce a tri-state output of the output stage (50) in response to a sensed value proportional to an amount of current that flows to the output node (81).

Abstract: An IC includes an externally accessible terminal, a filter, and an output stage. The filter has an adjustable bandwidth and has an output node coupled to the externally accessible terminal, and the output stage has an input node coupled to the output node of the filter. By providing access to a node that is between the filter and an amplitude-limiting output stage, the IC allows one to adjust the bandwidth of the filter—or the bandwidth of a circuit, such as an amplifier, that includes the filter—by measuring the amplitude of a signal that can have a relatively high S/N ratio without being clipped by the output stage. Consequently, such access can eliminate the need for a high-precision bandwidth-adjust setup and its long bandwidth-adjust times.

Abstract: A modulator receives an I-phase transmission data signal and a Q-phase transmission data signal, which have been spread-spectrum processed, and modulates an intermediate frequency signal in accordance with the data signals, an IF-AGC amplifier amplifies the output of the modulator, the gain of the IF-AGC amplifier being controlled in accordance with a gain control signal, an up-converter increases the output of the IF-AGC amplifier to a propagation frequency, the gain of the up-converter being controlled in accordance with a control signal.

Abstract: One aspect of the invention is an amplifier (10), comprising an input stage amplifier (20) coupled to an output node (81). The amplifier (10) further comprises a class D output stage (50), which comprises at least two switching elements (P1, N1) and coupled to the output node (81). The amplifier (10) also comprises a control circuit (40) coupled to the output stage (50). The control circuit (40) is operable to produce a tri-state output of the output stage (50) in response to a sensed value proportional to an amount of current that flows to the output node (81).

Abstract: Disclosed is a low-noise active RC signal processing circuit, which comprises a feedforward section operable responsive to an input signal to provide an output at a predetermined gain, and a feedback section operable responsive to the output of the forward circuit to negatively feed back the output to the input signal of the feedforward section while giving a predetermined transfer characteristic to the output, so as to allow the processing circuit to have a transfer impedance characteristic equal to or less than the predetermined gain over the entire frequency range. The feedforward section is composed of a current-controlled voltage output circuit which includes a common-base transistor for receiving and inverting the input signal, and an emitter-follower transistor for outputting voltage, and has a transfer impedance defining the predetermined gain. The current-controlled voltage output circuit may also be constructed using an operational amplifier.

Abstract: A novel and useful apparatus for and method of automatic gain control (AGC) using Kalman filtering and hysteresis. A nonlinear, time-variant loop filter such as a Kalman filter is employed in the feedback loop of an AGC circuit. The circuit is able to transition quickly and make fast adaptations to new levels of the input signal by use of a restart mechanism used to dynamically modify the gain of the loop filter thus enabling the AGC circuit to quickly adapt to changes in the signal level of the input. An AGC circuit incorporating a hysteresis circuit in the feedback loop is also disclosed.

Abstract: The present invention discloses a linearisation and modulation device for a power amplifier.

Abstract: A feed forward RF power amplifier which provides both high efficiency and minimal distortion in broad bandwidth RF applications. The feed forward power amplifier includes a main amplifier biased to provide high efficiency and an error amplifier biased to provide highly linear operation through substantially the entire operating range. Signal peaks which introduce distortion components at the main amplifier output are cancelled by the linear operation of the error amplifier.

Abstract: A line driver combining active impedance and filter in one stage for connection to a transmission line having a characteristic impedance. The line driver comprises an amplifier, a transformer with a primary to secondary winding ratio of 1:n, a reference impedance, an input impedance and two feedback impedances. The primary winding of the transformer has a first end connected to the output of the amplifier and the secondary winding is connectable to the transmission line. The reference resistor has an end connected to the second end of the first winding at a junction node and the feedback circuit is connected to the input and output of the amplifier and also to the junction node. The reference impedance has a value equal to n 2 K times the characteristic impedance of the transmission line.

Abstract: A line driver combining active impedance and filter in one stage for connection to a transmission line having a characteristic impedance. The line driver comprises an amplifier, a transformer with a primary to secondary winding ratio of 1:n, a reference impedance, an input impedance and two feedback impedances. The primary winding of the transformer has a first end connected to the output of the amplifier and the secondary winding is connectable to the transmission line. The reference resistor has an end connected to the second end of the first winding at a junction node and the feedback circuit is connected to the input and output of the amplifier and also to the junction node. The reference impedance has a value equal to n2 /K times the characteristic impedance of the transmission line. The feedback circuit is arranged to produce a voltage at the output of the amplifier substantially equal to (K+1) times the voltage at the junction node, for a predetermined value of K.

Abstract: A bandpass amplifier for use in a communication system is described. The amplifier includes a filter, a quantizer, a driver, and a feedback loop. The filter filters the input signal, thereby generating a filtered signal. The quantizer quantizes the filtered signal into one of two values, thereby generating a quantized signal. The driver amplifies the quantized signal, thereby generating the output signal. The feedback loop feeds the output signal to the filter. The quantizer has characteristics in which the quantized signal does not fluctuate between the two values when the input signal is substantially stable.

Abstract: A charge-type sensor amplifying circuit includes an operational amplifier having an inverting input terminal thereof connected to one terminal of a charge-type sensor, a voltage divider having two voltage-dividing points which divide the output voltage from the operational amplifier, a feedback resistor connected between the inverting input terminal of the operational amplifier and one voltage-dividing point of the voltage divider which is on the output terminal side of the operational amplifier, and a feedback capacitor connected in parallel with the feedback resistor. In the charge-type sensor amplifying circuit, the other terminal of the charge-type sensor is connected to the other voltage-dividing point of the voltage divider which is not on the output terminal side of the operational amplifier.

Abstract: An optical transmission apparatus includes a feedback amplification circuit having flat and wideband frequency characteristics in which the linearity within a band is excellent. As a result, frequency characteristics of the optical transmission apparatus are improved. A feedback amplification circuit is structured with an amplifier including a transistor receiving an input signal at the base thereof, a first feedback path including a feedback resistance provided between the input terminal and the output terminal of the amplifier, i.e.

Abstract: A method of controlling switching of a tri-state switching amplifier having two switching legs, two switches in each leg, and a load connected to the junction between the switches of each leg, a power supply and a capacitor connected to the opposite ends of each leg, a first pair of the switches defining an idle state in which current circulates through the load and the first pair of switches, a second pair of the switches defining a Charge state in which the load is connected to the power supply and current through the load increases and a third pair of switches defining a Discharge state in which the load is connected to the power supply and current through the load decreases, the method comprising generating a first PWM signal at the beginning of each pulse of a clock signal; generating a second PWM signal when a binary current error signal changes state; generating, at the beginning of each pulse of the clock signal, a Direction signal which is the inverse of the current error signal; and placing the ampl

Abstract: A circuit arrangement includes a feedback loop, with a forward path and a feedback path, and a re-combining stage. A measuring circuit is provided to produce a measuring signal derived from a result signal and a feedback signal by linear combination.

Abstract: An operational amplifier connected in series with a load and a current-measuring impedance and having at least two input ports and an output port, the output port of the operational amplifier further being directly connected to current-measuring impedance, with one of the input ports being coupled to the current input source to be measured, and the other input port being connected to a feedback loop coupled from the output side of the current-measuring impedance. The voltage across the current-measuring impedance which comprises a resistor is thereafter sensed, amplified and conditioned to provide a voltage which is proportional to the load current and accordingly a measure of the current input from the current source being measured. Such a current-measuring circuit can be used in connection with an inverter, a current-measuring amplifier, a current-measuring precision diode, a current integrator, and a current-measuring bridge.