10ppb
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Why does the differential amplifier not need capacitors at the input?
Accepted answer
5 votes

This circuit is dc coupled and is meant to work all the way to dc.

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Diode in place of manual switch for HV application
3 votes

These parts from VMI are typical of what is available, assuming we are talking about low power dissipation: https://www.voltagemultipliers.com/products/diodes/axial-lead-glass-body-diodes/ At 5 kV ...

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Lowering pitch sound of a piezoelectric buzzer
3 votes

Since you are using a pulse generator I’ll assume that you have bare transducer, rather than something with active circuitry. I’ll further guess that it is the common kind, a brass disk with a layer ...

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Help with 144Mhz small signal amplifier not amplifying
Accepted answer
2 votes

Your scope probe loads the circuit with about 16 pF or 70 Ohms at 144 MHz. The output impedance is higher, close to the value of the collector resistor. Thus you have very significant voltage ...

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Harmonics in transformers
1 votes

A bit more detail: because of core saturation, the output signal will vary linearly with the input signals only for small signals. When saturation first appears the predominant nonlinearity will be ...

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Is the use of a lock in amplifier with a signal generator appropriate and practicable?
1 votes

Yes, it makes sense in general terms. The lock-in you mention is a rather exotic thing with 50 MHz bandwidth. It is overkill for a 5 kHz signal. It might help to say a bit more about what you are ...

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Why do op amps need input protection when the input impedance is very high?
1 votes

In normal operation there is almost no input current, so there is also no voltage drop across the input protection resistors. However, during an ESD event the protection diodes turn on, and a current ...

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Equivalent noise resistance(s) - 2 stage amplifier
0 votes

No, those are two different resistances if you draw the diagram correctly. The question intends that your diagram contain ideal voltage amplifiers, which you should represent as triangles pointing to ...

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Is it possible to step up dc without changing it to ac or pulsed dc?
0 votes

Yes, there are switched capacitor voltage multipliers. In one type, you put a number of capacitors in parallel across the input voltage source. Then you reconnect them so they are applied to the load ...

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Avoiding thermal noise to enter low temperature while not using dissipative element
0 votes

Usually, in these situations what really matters is to avoid attenuation in the return path from the cryogenic device under test (shown at the top of the sketch), since you are trying to detect a ...

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Why does CMRR degrade in an instrumenation amplifier when the feedback resistor is increased?
0 votes

I assume you mean, as both instances of R3 are increased. (If you only change one of them, this is not a differential amplifier at all, so CMR will be very poor, as Andy aka explains.) In the ...

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Improving SNR by increasing resistor value
0 votes

Your reference is talking about the SNR of a source, where the signal is the voltage developed across a resistor from a fixed current flowing through the resistor, and the noise is the resistor’s ...

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Amplifier noise output against source resistance
0 votes

Besides the nice answer that has been given already, there are other possibilities, having to do with other things that might need to be added to your noise model. Is your source really just a ...

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In noise voltage equivalent circuit, why are the source and load resistances equal?
0 votes

The circuit is what it is, and the calculation correctly shows that the power dissipated in a matched load is kTB. (Power is not “developed across” a load, it is dissipated in a load.) Without more ...

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