All Questions
13
questions
1
vote
1
answer
27
views
is Vov of a nMos always VGS - Vt?
Looking at this graph from Analog Circuit Design Discrete and Integrated by Sergio Franco, is it always true that Vov = VGS - Vt? or is this only true at pinchoff point?
- 31
5
votes
3
answers
719
views
NMOS current is negative for a very short time when turning off
I am designing a circuit that uses the 2n7000 NMOS as a switch, controlled by a digital I/O pin from an Arduino Micro.
I made a simulation in LTspice, and I notice that when the NMOS is turning off ...
- 4,145
1
vote
1
answer
107
views
Current flow in PMOS when not active
how can it be that Q2 is active when VA and VB are HIGH?
If I understand correctly, a current (shown in yellow) should flow...
But that is in my understanding not possible because both NMOS are ...
- 13
1
vote
2
answers
371
views
Can two IRLZ44N MOSFETs in parallel handle a current of 20 A without heat sink?
Can two IRLZ44N MOSFETs in parallel handle a current of 20 A without a heat sink?
The Vgs command is a square wave at a frequency of 70 Hz.
Do I need to attach two big heat sinks or not?
Will my two ...
- 146
0
votes
4
answers
179
views
I'd like to know if I can push 40 volts at 3 amps through an IRLZ44N MOSFET?
I already have the datasheet, it states it can handle 50 volts at 50 amps but I'm worried about spikes since I'm using it to switch the primary side of the transformer at 70 Hz and it will be a square ...
- 146
0
votes
2
answers
342
views
Can I somehow make the LM7805 work hand in hand with an N-channel MOSFET to get more current out of the regulator?
I've seen the circuit with the LM7805 being used hand in hand with a PNP to provide more current.
My problem is the heat that comes with said configuration. Isn't there a way to make a linear ...
- 146
0
votes
1
answer
181
views
Simulation doubt with Zener diode & MOSFET
I have the below circuit in which I am trying to perform simulations.
Simulation Tool used - Falstad Simulator
12V Zener Diode
Top MOSFET
Bottom MOSFET
Question 1 :
The Zener diode is 12V Rated.
I ...
user220456
2
votes
4
answers
2k
views
Is the current, Ids, through a MOSFET truly 0 when in the cutoff region?
I was testing a circuit using this circuit simulator and found that the nMOS transistor had a current of a few nanoamps running through it when it was in the "off" state. This was unexpected because I ...
- 170
0
votes
0
answers
529
views
Rs and Rd in series in MOSFET circuit?
Can we consider Rs and Rd to be in series? That is, is the equation ID = (Vdd)/(Rd+Rs) correct?
What is confusing me is that they have the same current, but there's a voltage drop across the drain-...
- 95
0
votes
1
answer
58
views
differential amplifier and ac imput
hello im studying the differential amplifier from Sedra Smith and i have problem with the ac mode when the signal is differential (vid/2 and -vid/2)
I know that in Nmos transistor the current flows ...
- 147
1
vote
0
answers
47
views
finding two drain currents
below I have the following problem along with the circuit's picture
My analysis is as follows:
for G and D open
\begin{equation}
I_{D1}=I_{D2}\hspace{10mm}therefore\hspace{10mm}V_{ov1}=\:V_{ov2}
\...
- 299
0
votes
1
answer
423
views
High-side gate driver not working under load high current
I have been trying to implement a current limiting circuit using a high power NMOS and high side gate driver.
My idea is to adjust the PWM duty-cycle of the gate driver to give an limited (average) ...
0
votes
2
answers
197
views
Help with design of current DAC
I am required to design a current DAC (64 element NMOS) that sinks the current of another current DAC (16 element PMOS).
The specs are as follows:
1. The smallest current output from the PMOS DAC is ...
- 45