Questions tagged [source-follower]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
12
votes
4answers
323 views

How does adding a current source and extra resistor to source follower improve its performance?

This question is similar to FET - Source follower utilizing current source to lower voltage offset, although I do not entirely understand the explanations, which is why I am posting my own question. ...
2
votes
0answers
52 views

Need help for pointing out, source follower circuit with current source, designing NMOS

I'm not sure did I solve this problem right. I made \$ r_{o2} \$ , which is resistance looking at Q2 drain. So I can get $$ g_{m,Q3} = 1.8m(A/V) $$ from $$A_v = \frac{r_{o2} || r_{o3}}{1/g_m + (r_{o2} ...
0
votes
0answers
38 views

Having trouble in designing mosfet source follower with current mirror

I know small signal voltage gain is 0.9V/V, and I know the equation of transconductance in pi-model $$A_v = \frac{r_o || R_L}{1/g_m + (r_o || R_L)}$$ But in this problem there is no connected \$ R_L \...
1
vote
2answers
100 views

Source Resistor of JFET Source-Follower

I am designing a simple Buffer to get the voltage of a high-impedanze source to an ADC (60k Impedance). For that I choosed an JFET in the source-follower configuration. simulate this circuit – ...
0
votes
1answer
45 views

I would like to know if the circuit is correct?

simulate this circuit – Schematic created using CircuitLab I have used the voltage follower concept in order to keep the output logic non-inverted.I would like to know the issues that I might ...
0
votes
1answer
372 views

CMOS source follower with 2 in series

I am really struggling with where to start to analyse this. Using the Shichman Hodges Model and the small signal equivalent circuit, the voltage gain can be equation can be seen to be vo = -gmvgsr0. ...
2
votes
0answers
64 views

Reducing the offset voltage of a source follower

I am currently trying to reduce the offset voltage of the circuit attached below to less than +/- 2mV over a 1V to 4V input range. I have a few constraints for this task: I can use ...
2
votes
3answers
1k views

Strange output with a LM7171 opamp (non-inverser amplifier)

I have a continuous input signal with a very high impedance and I need an output signal with a low impedance of 50Ω. That's why I've considered the LM7171 (High Output Current: 100 mA). I've tried to ...
1
vote
1answer
64 views

Tuning a potential sensor using a source-follower MOSFET

I am interested in building a simple but sensitive setup that would allow me to detect small potential changes (adsorption of ions) on the surface of the gate of a MOSFET - what is commonly referred ...
0
votes
1answer
69 views

Can I use a source follower to read the floating gate voltage then add a fixed tunneling voltage, then feed it back to the tunneling electrode?

So I was reading this research paper: H. Kosaka, T. Shibata, H. Ishii, and T. Ohmi, “An excellent weightupdating-linearity synapse memory cell for self-leaming neuron MOS neural networks,” in IEDM ...
0
votes
0answers
100 views

How can I reduce loading effect in dc common drain source follower?

I want to make a dc voltage buffer using an nmos source follower. I found that by making Rs as large as possible or even open, Vs= Vgs-Vth. I verified it using multisim. The problem is it suffers from ...
0
votes
2answers
2k views

What are the Advantage and uses of voltage follower circuit over emitter follower

Can I use voltage follower and emitter follower for same purpose
1
vote
1answer
601 views

Source follower basic question

I just want to clear my understanding about a basic source follower circuit. Following is the circuit Here is my question: Considering Vi > Vgs(th); Vo = Vi - Vgs. Also Vo = Id*Rs as shown in the ...
0
votes
2answers
590 views

Stability problem OpAmp and FET source follower

I just found this site and read a few great interesting articles but nothing that would solve my problem I am hunting since a while. I have a OpAmp circuit with a N-FET source follower that regulates ...
0
votes
1answer
371 views

Follower current source?

I need advice on a problem I'm having I need a follower to transmit an AC signal into a low impedance load which is the cathode of a triode but I also need it to be an adjustable current source to ...
2
votes
1answer
730 views

Source Follower Output Biasing

I am trying to understand the Source Follower amplifier as a primitive buffer, and am running some simulations with a SPICE simulator. I have the amplifier hooked up as shown below with a current ...