摘要:
An amplifier circuit includes first (7A) and second (7B) operational amplifiers connected in a parallel configuration. A first terminal (12) of a first input resistor (5) is coupled to one input of both of the first (7A) and second (7B) amplifiers. A first terminal (15) of a second input resistor (6) is coupled to another input of both of the first (7A) and second (7B) amplifiers. A differential input voltage is applied between the second terminals of the first and second input resistors. The output signals of the first (7A) and second (7B) operational amplifiers are combined to produce an output signal (11AB) representative of feedback currents produced in the first (5) and second (6) input resistors. Upper and lower common mode input voltage ranges associated with the differential input voltage extend substantially above and below the upper and lower supply voltages, respectively, of the amplifier circuit.
摘要:
An integrated circuit photodetector includes a transimpedance amplifier including a differential amplifier stage with PNP emitter-coupled transistors and a PNP input transistor which are biased only by base currents of the emitter-coupled transistors, to achieve low input bias current. Low noise operation is achieved by bypass capacitors coupled between the bases and emitters of the input transistors, respectively. A constant current source supplies a current which develops a small pedestal voltage across a resistor to bias the non-inverting input of the transimpedance amplifier so as to avoid nonlinear amplification of low level light signals. A positively biased N-type guard tub surrounds the photodetector, which is formed in a junction-isolated N region on a P substrate, to collect electrons generated in the substrate by deep-penetrating IR light to prevent them from causing amplification errors. In one embodiment, a feedback network includes a resistor connected between the output of a buffer driven by the transimpedance amplifier and an inverting input thereof, and a capacitor connected between the output and inverting input of the transimpedance amplifier to provide low noise, fast settling operation.
摘要:
An integrated circuit current shunt amplifier (2A) includes an amplifier (9) having a (+) input connected to a first terminal (5A) of a shunt resistor (RSHUNT). An output transistor (24) has a gate coupled to an output of the amplifier, a source coupled to a (−) input of the amplifier, and a drain coupled to a first terminal of an output resistor (ROUT). A gain resistor (RGAIN) is coupled between the (−) input of the amplifier and a second terminal of the shunt resistor. The gain resistor has a temperature coefficient which is essentially the same as that of the shunt resistor. A voltage regulator (26) can be coupled between the second terminal of the shunt resistor and a low-side supply voltage terminal (27) of the amplifier. A charge pump (30) can provide a below-ground voltage on a second terminal of the output resistor. A difference amplifier (31) coupled to the drain and referenced to the below-ground voltage produces an output voltage (Vout) referenced to ground.
摘要:
Systems and methods are disclosed for communicating on a pilot wire between Electric Vehicle Service Equipment (EVSE) and an Electric Vehicle (EV). The EVSE and EV exchange a Pulse Width Modulation (PWM) signal on the pilot wire to control charging operations of the EV. Data communications may also be transmitted on the pilot wire, such as between transmit and receive modems. The modems transmit communication signals either continuously, without regard to the state of the PWM signal, or only when the PWM is in an off-state. If transmitting while PWM is on, the modem needs a large coupling impedance and/or a large signal injection. To transmit only when the PWM is off, the modem may use a blocking diode in the coupling circuit or may synchronize to the pulses in the PWM signal.
摘要:
Coupling circuits for power line communication (PLC) devices are described. In an embodiment, a PLC device may comprise a processor and a coupling circuit coupled to the processor. The coupling circuit may in turn comprise a transmitter path and a receiver path. In some implementations, the transmitter path may include a first amplifier, a first capacitor coupled to the first amplifier, a first transformer coupled to the first capacitor, and a plurality of line interface coupling circuits coupled to the first transformer, where each of the line interface coupling circuits is configured to be connected to a different phase of an electrical power circuit. Meanwhile, the receiver path may include a plurality of capacitors, where each of the plurality of capacitors coupled to a corresponding one of the line interface circuits, a filter network coupled to the plurality of capacitors, and a second amplifier coupled to the filter network.
摘要:
Systems and methods are disclosed for communicating on a pilot wire between Electric Vehicle Service Equipment (EVSE) and an Electric Vehicle (EV). The EVSE and EV exchange a Pulse Width Modulation (PWM) signal on the pilot wire to control charging operations of the EV. Data communications may also be transmitted on the pilot wire, such as between transmit and receive modems. The modems transmit communication signals either continuously, without regard to the state of the PWM signal, or only when the PWM is in an off-state. If transmitting while PWM is on, the modem needs a large coupling impedance and/or a large signal injection. To transmit only when the PWM is off, the modem may use a blocking diode in the coupling circuit or may synchronize to the pulses in the PWM signal.
摘要:
Coupling circuits for power line communication (PLC) devices are described. In an embodiment, a PLC device may comprise a processor and a coupling circuit coupled to the processor. The coupling circuit may in turn comprise a transmitter path and a receiver path. In some implementations, the transmitter path may include a first amplifier, a first capacitor coupled to the first amplifier, a first transformer coupled to the first capacitor, and a plurality of line interface coupling circuits coupled to the first transformer, where each of the line interface coupling circuits is configured to be connected to a different phase of an electrical power circuit. Meanwhile, the receiver path may include a plurality of capacitors, where each of the plurality of capacitors coupled to a corresponding one of the line interface circuits, a filter network coupled to the plurality of capacitors, and a second amplifier coupled to the filter network.
摘要:
An integrated circuit current shunt amplifier (2A) includes an amplifier (9) having a (+) input connected to a first terminal (5A) of a shunt resistor (RSHUNT). An output transistor (24) has a gate coupled to an output of the amplifier, a source coupled to a (−) input of the amplifier, and a drain coupled to a first terminal of an output resistor (ROUT). A gain resistor (RGAIN) is coupled between the (−) input of the amplifier and a second terminal of the shunt resistor. The gain resistor has a temperature coefficient which is essentially the same as that of the shunt resistor.A voltage regulator (26) can be coupled between the second terminal of the shunt resistor and a low-side supply voltage terminal (27) of the amplifier. A charge pump (30) can provide a below-ground voltage on a second terminal of the output resistor. A difference amplifier (31) coupled to the drain and referenced to the below-ground voltage produces an output voltage (Vout) referenced to ground.
摘要:
An amplifier circuit includes first (7A) and second (7B) operational amplifiers connected in a parallel configuration. A first terminal (12) of a first input resistor (5) is coupled to one input of both of the first (7A) and second (7B) amplifiers. A first terminal (15) of a second input resistor (6) is coupled to another input of both of the first (7A) and second (7B) amplifiers. A differential input voltage is applied between the second terminals of the first and second input resistors. The output signals of the first (7A) and second (7B) operational amplifiers are combined to produce an output signal (11AB) representative of feedback currents produced in the first (5) and second (6) input resistors. Upper and lower common mode input voltage ranges associated with the differential input voltage extend substantially above and below the upper and lower supply voltages, respectively, of the amplifier circuit.
摘要:
An integrated circuit photodetector includes a transimpedance amplifier including a differential amplifier stage with PNP emitter-coupled transistors and a PNP input transistor which are biased only by base currents of the emitter-coupled transistors, to achieve low input bias current. Low noise operation is achieved by bypass capacitors coupled between the bases and emitters of the input transistors, respectively. A constant current source supplies a current which develops a small pedestal voltage across a resistor to bias the non-inverting input of the transimpedance amplifier so as to avoid nonlinear amplification of low level light signals. A positively biased N-type guard tub surrounds the photodetector, which is formed in a junction-isolated N region on a P substrate, to collect electrons generated in the substrate by deep-penetrating IR light to prevent them from causing amplification errors. In one embodiment, a feedback network includes a resistor connected between the output of a buffer driven by the transimpedance amplifier and an inverting input thereof, and a capacitor connected between the output and inverting input of the transimpedance amplifier to provide low noise, fast settling operation.