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How do you simulate output resistance?
To simulate the output impedance, simply ground the inputs and connect an ac current source to the output node. Note that ZOUT = VOUT/IOUT. Since IOUT = 1 (ac source), the magnitude of the output voltage corresponds to the output impedance. By plotting the frequency response, the output impedance can be analyzed.
What techniques increase input resistance?
Bootstrapping: This is the most effective method of increasing the input resistance. The input resistance is of the order of 10 mega-ohm. Biasing it at low quiescent current: In this method the input resistance is of the order of few kilo-ohms.
Which is the highest input resistance?
1. Which among the following circuit has the highest input resistance? Explanation: Voltage follower has the highest positive input resistance of any op-amp circuit.
How to simulate the input / output impedance of opamp?
The answer completely depends on the purpose of your simulation, that is still unclear. If you connect a load with sufficient high input resistance, you can simply model the sensor as a voltage source, as suggested by checkmate. Obviously, the simulation won’t give much insights. You set a voltage and the ADC will measure it.
How to measure the impedance of an input?
The input is a constant current source, its value set to 1amp. As the current sources in most simulation programs are perfect and have an infinite output impedance, you will have to use a high value resistor in parallel, as shown, to avoid simulation errors. As V= I * Z, and using 1 amp as shown for the current source, hence V=1*Z or V=Z.
How are parallel resistors used in impedance matching networks?
With a parallel resistor, you have the opposite effect. The parallel resistor effectively reduces the equivalent impedance of the load+terminating resistor parallel circuit so that it matches the transmission line impedance. Six useful impedance matching networks are shown in the figure below:
How to design and simulate an impedance matching network?
There are several possible impedance matching networks to choose from. The simplest matching networks place a resistor in series or in parallel (connected to ground) with either the load.