摘要:
The present disclosure provides a circuit that has an electrostatic discharge (ESD) protection device and a protected circuit in communication with the ESD protection device. The ESD protection device has a first inductor between a signal input terminal and a complimentary power line. The first inductor has a length less than ¼ of a normal operating wavelength of the protected circuit. The ESD protection device also has a first capacitor between the signal input terminal and the protected circuit.
摘要:
A voltage clamping module is disposed at an output terminal of a gain amplifying module, so that a voltage level of an amplifying signal outputted by the gain amplifying module can be clamped within a predetermined range. The voltage clamping module includes an upper bound voltage clamping module, which is utilized for limiting the voltage level of the amplifying signal to be lower than an upper bound voltage level, and a lower bound voltage clamping module, which is utilized for limiting the voltage level of the amplifying signal to be higher than a lower bound voltage level.
摘要:
The disclosure provides an operational amplifier circuit, in which a power supply of an amplifying circuit is coupled to a first voltage clamping circuit, and the first voltage clamping circuit clamps a supply voltage of the amplifying circuit when the supply voltage exceeds a normal-operation allowable voltage of the amplifying circuit. The disclosure also provides a method for implementing the operational amplifier circuit. According to the disclosure, the operational circuit may be avoided from subject to an excessive supply voltage, which may damage devices in the amplifying circuit of the operational amplifier.
摘要:
An output buffer circuit for avoiding voltage overshoot includes an input stage, an output bias circuit, an output stage, a clamp circuit, and a control unit. The input stage includes a positive input terminal, for receiving an input voltage, and a negative input terminal. The input stage generates a current signal according to the input voltage. The output bias circuit is coupled to the input stage, for generating a dynamic bias according to the current signal. The output stage is coupled to the input stage and the output bias circuit, including an output terminal, reversely coupled to the positive input terminal, and at least one output transistor, coupled to the output bias circuit and the output terminal, for providing a driving current to the output terminal according to the dynamic bias to generate an output voltage.
摘要:
An amplifier (e.g., an LNA) with improved ESD protection circuitry is described. In one exemplary design, the amplifier includes a transistor, an inductor, and a clamp circuit. The transistor has a gate coupled to a pad and provides signal amplification for the amplifier. The inductor is coupled to a source of the transistor and provides source degeneration for the transistor. The clamp circuit is coupled between the gate and source of the transistor and provides ESD protection for the transistor. The clamp circuit may include at least one diode coupled between the gate and source of the transistor. The clamp circuit conducts current through the inductor to generate a voltage drop across the inductor when a large voltage pulse is applied to the pad. The gate-to-source voltage (Vgs) of the transistor is reduced by the voltage drop across the inductor, which may improve the reliability of the transistor.
摘要:
An ESD clamp circuit applied to a power amplifier is provided. The ESD clamp circuit includes a first line, a second line, a first circuit, a second circuit, an ESD detecting unit, a buffer unit, and an ESD clamp unit. The first line is coupled to the output terminal of the power amplifier. The first circuit is coupled to the first line. The second circuit is coupled to the first circuit. The ESD detecting unit is coupled to the first circuit and the second line. The buffer unit is coupled to the second circuit, the second line and the ESD detecting unit. The ESD clamp unit is coupled to the buffer unit, the first line and the second line. Therefore, at normal operation mode, the problem of signal loss caused by the leakage current of ESD clamp circuit can be avoided.
摘要:
The present invention relates to an electrostatic discharge (ESD) clamp circuit that is used to protect other circuitry from high voltage ESD events. The ESD clamp circuit may include a field effect transistor (FET) element as a clamping element, which is triggered by using a drain-to-gate capacitance, a drain-to-gate resistance, or both of the FET element, and a resistive element as a voltage divider to divide down an ESD voltage to provide a triggering gate voltage of the FET element. In its simplest embodiment, the ESD clamp circuit includes only an FET element and a resistive element. Therefore, the single FET element ESD clamp circuit may be small compared to other ESD protection circuits. The simplicity of the ESD clamp circuit may minimize parasitic capacitances, thereby maximizing linearity of the ESD clamp circuit over a wide frequency range.
摘要:
An ESD clamp circuit applied to a power amplifier is provided. The ESD clamp circuit includes a first line, a second line, a first circuit, a second circuit, an ESD detecting unit, a buffer unit, and an ESD clamp unit. The first line is coupled to the output terminal of the power amplifier. The first circuit is coupled to the first line. The second circuit is coupled to the first circuit. The ESD detecting unit is coupled to the first circuit and the second line. The buffer unit is coupled to the second circuit, the second line and the ESD detecting unit. The ESD clamp unit is coupled to the buffer unit, the first line and the second line. Therefore, at normal operation mode, the problem of signal loss caused by the leakage current of ESD clamp circuit can be avoided.
摘要:
An active over-voltage clamp system includes at least one over-voltage detector that is responsive to an input voltage and provides a first current. The system also includes a replica over-voltage circuit that provides a second current, and circuitry subtracting the second current from the first current to produce a difference current. The system further includes a differential clamp activated in response to the difference current. The differential clamp prevents the input voltage from increasing beyond a target voltage.
摘要:
An amplifier system includes an instrumentation amplifier arrangement being designed to amplify the difference between two voltage inputs with a defined gain, and to produce a single-ended output referenced to a known reference point. A front end circuit is coupled to the instrumentation amplifier. The front end circuit is configured to include a current clamp to actively limit the current in a gain resistor of the instrumentation amplifier to prevent input currents flowing when the instrumentation amplifier is over-driven.