Abstract: A fully-differential two-stage operational amplifier circuit is provided, and it includes a first-stage amplification circuit, a second-stage amplification circuit, a common-mode signal acquisition circuit, a common-mode feedback circuit and a bias circuit. The first-stage amplification circuit has a telescopic structure and receives differential input signals INP and INN. The second-stage amplification circuit has a common-source structure and outputs differential output signals OUTP and OUTN. The common-mode signal acquisition circuit receives differential output signals, and outputs an operational amplifier output common-mode signal VCMO. The common-mode feedback circuit outputs common-mode feedback signals VB1 and VB2 to the first-stage amplifier circuit and the second-stage amplifier circuit respectively; The bias circuit outputs a bias voltage VB3 to the first-stage amplifier circuit, and outputs bias voltages VB4 and VB5 to the first-stage amplifier circuit respectively.

Abstract: A CMOS trans-impedance amplifier includes an inverting amplifier circuit and a feedback resistor. The inverting amplifier circuit includes an input end and an output end, and the feedback resistor is coupled therebetween. The inverting amplifier circuit includes at least three sequentially-connected amplifier units, and each amplifier unit includes at least three sequentially-connected nFETs, namely an input signal receiving part nFET, an intermediate part nFET and a DC signal receiving part nFET. A common connection terminal of the input signal receiving part nFET and the intermediate part nFET is configured to output an amplified voltage signal.

Abstract: A CMOS trans-impedance amplifier includes an inverting amplifier circuit and a feedback resistor. The inverting amplifier circuit includes an input end and an output end, and the feedback resistor is coupled therebetween. The inverting amplifier circuit includes at least three sequentially-connected amplifier units, and each amplifier unit includes at least three sequentially-connected nFETs, namely an input signal receiving part nFET, an intermediate part nFET and a DC signal receiving part nFET. A common connection terminal of the input signal receiving part nFET and the intermediate part nFET is configured to output an amplified voltage signal.

Abstract: This invention provides an accurate current mirror circuit in a low voltage headroom applied to common-anode laser drivers, including a reference current detection unit, a tail current source unit, and a control unit. The reference current detection unit generates a bias voltage and a reference voltage according to a reference current from the reference current source; the tail current source unit receives the bias voltage and generate a mirror current accordingly; the control unit receives the reference voltage and an output voltage corresponding to the mirror current and carry out a feedback regulation to the bias voltage accordingly. In this invention, the reference voltage and the output voltage are locked at same level, and then the bias voltage is mirrored to generate the mirror current outputted to the laser, thus avoiding the problem of inaccurate current output caused by the offset of the control unit in the low voltage headroom.

Abstract: This invention provides a relaxation oscillator, including a first comparator, a second comparator, an SR latch, and a capacitor control module. Input ends of the two comparators are coupled with the capacitor control module and an external reference threshold voltage, and two output ends are coupled with the input ends of the SR latch; output ends of the SR latch are coupled with input ends of the capacitor control module; According to the external reference threshold voltage, a first comparison signal generated by the first comparator and a second comparison signal generated by the second comparator are inputted into the SR latch to generate a control signal. According to a bias current of the external bias current source and the control signal outputted by the SR latch, periodic charging and discharging of a first capacitor and a second capacitor are controlled to generate oscillating signals.

Abstract: The present disclosure provides a trans-impedance amplifier, comprising: an inverting amplifier circuit, having an input end and an output end. The input end is coupled to an optical diode and is used for accessing an input voltage signal, and the output end is used for outputting an amplified voltage signal. The inverting amplifier circuit comprises at least three sequentially-connected amplifier units. Each of the amplifier units comprises two mutually-coupled N-type transistors, wherein one N-type transistor is used for receiving an input voltage, and the other N-type transistor is used for receiving a DC voltage signal. A common connection end of the two N-type transistors is used for outputting an amplified voltage signal, and the N-type transistor used for receiving the DC voltage signal adopts a native NFET. The trans-impedance amplifier further comprises a feedback resistor coupled to the input end and the output end of the inverting amplifier circuit.

Abstract: This invention provides a relaxation oscillator, including a first comparator, a second comparator, an SR latch, and a capacitor control module. Input ends of the two comparators are coupled with the capacitor control module and an external reference threshold voltage, and two output ends are coupled with the input ends of the SR latch; output ends of the SR latch are coupled with input ends of the capacitor control module; According to the external reference threshold voltage, a first comparison signal generated by the first comparator and a second comparison signal generated by the second comparator are inputted into the SR latch to generate a control signal. According to a bias current of the external bias current source and the control signal outputted by the SR latch, periodic charging and discharging of a first capacitor and a second capacitor are controlled to generate oscillating signals.

Abstract: This invention provides an accurate current mirror circuit in a low voltage headroom applied to common-anode laser drivers, including a reference current detection unit, a tail current source unit, and a control unit. The reference current detection unit generates a bias voltage and a reference voltage according to a reference current from the reference current source; the tail current source unit receives the bias voltage and generate a mirror current accordingly; the control unit receives the reference voltage and an output voltage corresponding to the mirror current and carry out a feedback regulation to the bias voltage accordingly. In this invention, the reference voltage and the output voltage are locked at same level, and then the bias voltage is mirrored to generate the mirror current outputted to the laser, thus avoiding the problem of inaccurate current output caused by the offset of the control unit in the low voltage headroom.

Abstract: The present disclosure provides a trans-impedance amplifier, comprising: an inverting amplifier circuit, having an input end and an output end. The input end is coupled to an optical diode and is used for accessing an input voltage signal, and the output end is used for outputting an amplified voltage signal. The inverting amplifier circuit comprises at least three sequentially-connected amplifier units. Each of the amplifier units comprises two mutually-coupled N-type transistors, wherein one N-type transistor is used for receiving an input voltage, and the other N-type transistor is used for receiving a DC voltage signal. A common connection end of the two N-type transistors is used for outputting an amplified voltage signal, and the N-type transistor used for receiving the DC voltage signal adopts a native NFET. The trans-impedance amplifier further comprises a feedback resistor coupled to the input end and the output end of the inverting amplifier circuit.

Abstract: The present disclosure provides a trans-impedance amplifier, comprising: an inverting amplifier circuit, having an input end and an output end. The input end is coupled to an optical diode and is used for accessing an input voltage signal, and the output end is used for outputting an amplified voltage signal. The inverting amplifier circuit comprises at least three sequentially-connected amplifier units. Each of the amplifier units comprises two mutually-coupled N-type transistors, wherein one N-type transistor is used for receiving an input voltage, and the other N-type transistor is used for receiving a DC voltage signal. A common connection end of the two N-type transistors is used for outputting an amplified voltage signal, and the N-type transistor used for receiving the DC voltage signal adopts a native NFET. The trans-impedance amplifier further comprises a feedback resistor coupled to the input end and the output end of the inverting amplifier circuit.

Abstract: The present disclosure provides a trans-impedance amplifier, comprising: an inverting amplifier circuit, having an input end and an output end. The input end is coupled to an optical diode and is used for accessing an input voltage signal, and the output end is used for outputting an amplified voltage signal. The inverting amplifier circuit comprises at least three sequentially-connected amplifier units. Each of the amplifier units comprises two mutually-coupled N-type transistors, wherein one N-type transistor is used for receiving an input voltage, and the other N-type transistor is used for receiving a DC voltage signal. A common connection end of the two N-type transistors is used for outputting an amplified voltage signal, and the N-type transistor used for receiving the DC voltage signal adopts a native NFET. The trans-impedance amplifier further comprises a feedback resistor coupled to the input end and the output end of the inverting amplifier circuit.

Abstract: The present invention provides a burst mode trans-impedance amplifier, comprising: a voltage input circuit, used for sensing an optical signal and converting the optical signal into an input voltage signal; a differential circuit, having two input ends and an output end, wherein one input end is coupled to the voltage input circuit and is used for receiving the input voltage signal, the other input end is coupled to a threshold voltage signal, and the output end is used for regulating and outputting a differential voltage signal according to the input voltage signal and the threshold voltage signal; and a feedback regulation circuit, having an input end and an output end, wherein the input end is coupled to the output end of the differential circuit and is used for receiving the differential voltage signal, and the output end is coupled to the voltage input circuit.

Abstract: The present disclosure provides a trans-impedance amplifier, comprising: an equivalent secondary amplifier module, having an input end and an output end, wherein the input end is coupled to an optical diode and used for accessing an input voltage signal, and the output end is used for outputting a secondarily amplified first voltage signal; an inverting amplifier unit, coupled to the output end of the equivalent secondary amplifier module and used for accessing the first voltage signal and outputting an inverting amplified voltage signal, the inverting amplifier unit comprising a third N-type transistor and a fourth N-type transistor coupled to the third N-type transistor; and a feedback resistor, coupled to the input end of the equivalent secondary amplifier module and an output end of the inverting amplifier unit. The feedback resistor of the trans-impedance amplifier can be not restricted by original conditions, may increase resistance, reduce input noise and improve sensitivity.

Abstract: The invention relates to amplifiers and in particular, to a transimpedance amplifier for high rate applications. Disclosed is a two stage transimpedance amplifier having a first stage comprising an amplifier and a load and a second stage comprising an amplifier and a resistor. Negative feedback is provided through a feedback resistor. Only two voltage conversions occur which reduces phase distortion, as compared to three stage transimpedance amplifiers which perform 3 voltage conversions.

Abstract: An integrator circuit cancels a DC offset component related to an average DC value of a burst mode input signal from the output of an amplifier. The integrator circuit outputs an average DC value of the input signal in a response time that is shorter than the preamble of a burst mode signal. The integrator output signal remains stable within selected amplitude limits for a length of time corresponding to the data portion of a burst mode signal. A transimpedance amplifier embodiment of the invention comprises a TIA gain stage, an integrator, and a voltage-controlled current course. Other embodiments comprise an amplifier for converting single-ended input signals to differential output signals, an amplifier for differential output offset cancellation, a monolithic semiconductor integrated circuit die, and a packaged semiconductor integrated circuit device.

Abstract: An integrator circuit cancels a DC offset component related to an average DC value of a burst mode input signal from the output of an amplifier. The integrator circuit outputs an average DC value of the input signal in a response time that is shorter than the preamble of a burst mode signal. The integrator output signal remains stable within selected amplitude limits for a length of time corresponding to the data portion of a burst mode signal. A transimpedance amplifier embodiment of the invention comprises a TIA gain stage, an integrator, and a voltage-controlled current course. Other embodiments comprise an amplifier for converting single-ended input signals to differential output signals, an amplifier for differential output offset cancellation, a monolithic semiconductor integrated circuit die, and a packaged semiconductor integrated circuit device.

Abstract: The invention relates to amplifiers and in particular, to a transimpedance amplifier for high rate applications. Disclosed is a two stage transimpedance amplifier having a first stage comprising an amplifier and a load and a second stage comprising an amplifier and a resistor. Negative feedback is provided through a feedback resistor. Only two voltage conversions occur which reduces phase distortion, as compared to three stage transimpedance amplifiers which perform 3 voltage conversions.

Abstract: A process control system controls a non-self regulating process through a control output signal based on a set point and a measured process variable. The process control system includes a control circuit having a set point input, a process variable input and a control output. The control circuit generates the control output signal on the control output as a function of the set point received on the set point input and the measured process variable received on the process variable input. An auto-tuning circuit excites the process, estimates a process model based on an intersection between rising and falling asymptotes of the measured process variable, and then tunes the control function to the process based on the process model. The auto-tuning circuit obtains robust results, but is computationally simple such that the circuit can be implemented with hardware or software in low-power and low-memory applications, such as in field-mounted controllers.

Abstract: A process controller controls an integrating-type process based on a measured process variable and a set point. The process controller includes an error generating circuit, a non-integrating control circuit and an adaptive bias circuit. The error generating circuit generates an error signal based on a difference between the set point and the measured process variable. The control circuit generates a control signal as a function of the error signal. The adaptive bias circuit adds a bias value to the control signal, the measured process variable or the set point. The bias value is selectively updated as a function of the error signal to force the error signal toward zero.

Abstract: A process control system controls a process through a control output signal based on a set point and a measured process variable. The process control system includes a control circuit having a set point input, a process variable input and a control output. The control circuit generates the control output signal on the control output as a function of the set point received on the set point input and the measured process variable received on the process variable input. An auto-tuning circuit excites the process, estimates a process model based on a rising dead time, a rising rate-of-change, a falling dead time and a falling rate-of-change in the measured process variable and then tunes the control function to the process based on the process model. The auto-tuning circuit obtains robust results, but is computationally simple such that the circuit can be implemented with hardware or software in low-power and low-memory applications, such as in such in field-mounted control units.