The source tag has no usage guidance.
-5
votes
2answers
106 views
How to increase microntroller pin Source and Sink Capacity
I'm working on a project but I've hit a block now. I need to drive a total of 169 LEDs using 26 pins at worst case all may be ON at once. I'm afraid that this may fry the MCU since 200mA is absolute ...
0
votes
0answers
44 views
Battery powering two LED's with a led driver
Currently I am working on an application that is battery powered. I have two reflective sensors (RPR220 and RPR220-PC30N) which I am comparing to eachother. As a power supply I use 4 AA none ...
0
votes
1answer
40 views
calculate unknown source potential
In order to prepare for an exam in electro technics I have a specific task:
I have the following measurements of an unknown circuit:
\$(1)\quad U_{2(1)} = 4.28V \quad @ I_{(1)}=0.67A \$
\$(2)\quad ...
0
votes
1answer
105 views
Body Diode of a MOSFET
So for some MOSFETs, specially with Power MOSFETs, the body diode is a flyback diode that (as far as aI can tell) can be conveniently added to the MOSFET's bulk as there already PN junctions (correct ...
1
vote
4answers
111 views
Current source or current mirror?
I've been told that using current sources in simulation programs may produce "too optimistic" results compared to using current mirrors.
Could someone please elaborate? I'm still a bit confused about ...
0
votes
2answers
63 views
What is the current source for in the Schmitt trigger?
What is the current source for in the schmitt trigger? I can't understand this. Can't see any resistor either.
0
votes
1answer
54 views
what would the drain voltage be if NMOS source voltage is not ground?
Hi I'm a beginner trying to learn CMOS cuicuit.
Let's say we have two NMOS connected as shown.
Given: A, B, C are connected to Vdd = 5V;
VtM1 = 0.6V is the threshold voltage of M1;
VtM2 = 0.5V ...
-3
votes
2answers
114 views
6A Current Source [closed]
Hi I am designing a 6A current source. I know how to design a current source I am just looking for suggested materials that can handle the full 6A. The op amps and transistors that I have now are more ...
0
votes
4answers
177 views
how much energy is required to create a sound with constant frequency and amplitude?
Ok, this is a theoretical question, (Forgive my poor English, I am not a native speaker).
Lets assume that I have a power-source with p unknown.
this power-source provides energy to a speaker to ...
1
vote
1answer
13 views
Source Transformations resistor on bottom?
I know that source transformations work as shown in the top part of the attached image but what happens when the resistor is placed in a different location?
Does this give the same result? If so, ...
2
votes
3answers
97 views
why isn't Norton transform applicable on ideal sources?
An ideal voltage source has no resistance in series to it, so the it's transform the current source must have zero resistance in parallel to it.
This means that all the current passes through the ...
0
votes
1answer
87 views
Whether Internal source resistance will have effect on the circuit
Calculate the voltage gain for the network of Fig. 3.12 if the source has an internal
resistance of 100 in series with Vi.Vi=500mV,R= 1K ?
For this problem I had tried a solution but I am not ...
0
votes
1answer
147 views
Can source transformation be used to internal circuit (source) while finding thevenin equivalent of the source?
At first, I'm very sorry because I don't have money for circuit lab so there is not much visual circuit that clarify my steps
I have practiced source-transformation as well as Thevenin equivalent ...
1
vote
4answers
102 views
Current Source Circuit Internal Impedance
So I've been learning about current source circuits - this one in particular. I'm told that an ideal current source should give out the current no matter what happens to the load. But it should also ...
1
vote
2answers
90 views
Problem with a circuit of an controlled variable voltage source
I have this circuit, it should regulate the output voltage between 15V and 0V. But the output I get when I simulate it is between 2V and 3V, and when I implemented, I burned zener diode 1N4734A. ...
0
votes
0answers
37 views
How does the impedance of the source effect the positive sequence impedance measurements of distance relays?
How does the impedance of the source effect the positive sequence measurements of distance relays in relation to power system protection? I wrote that increasing the source impedance decreases the ...
0
votes
1answer
270 views
PSpice OrCAD Adding Diode and Unknown Source
On the PSPice OrCAD, how do you add a diode with a 0.7V forward bias and a unknown voltage source?
0
votes
2answers
967 views
Could we remove the resistor in parallel with voltage source or in series with current source?
Although this question have been asked. But I want to ask again. I still doubt about it. It is written in "Electric Circuits (9th Edition) by James W. Nilsson, Susan Riedel". And if we remove it, I ...
1
vote
2answers
184 views
Does source transformation in circuit analysis work the other way around?
We all know that the source transformation shown in the first picture below is valid. But does it also work in reverse, as shown in the second picture? (because I use proteus to draw second picture, ...
-1
votes
1answer
63 views
Which Clock Would Run Faster [closed]
I have two identical clocks: one is plugged into 120 VAC @ 60 Hz. The other is running on a 12 volt battery. Which would run faster, and more importantly, WHY?
Based on my understanding of a quartz ...
0
votes
2answers
78 views
Short the circuit of a voltage controlled voltage source when finding out the v(t) for \$t>0\$
Question
Find v(t) for t<0 and t>0 in the circuit below.
Solution
My Question
Why we can see the voltage controlled voltage source as a shorted circuit when finding the v(t) for ...
0
votes
1answer
40 views
Current of a circuit with regulator
When the specification of a regulator says that output is 1A for example the whole current of the circuit will be 1A?
For example I have a regulator in series with a 100Ω resistor and a 7V source.The ...
2
votes
1answer
227 views
Operational amplifier circuit with one ac and one dc voltage source
The following circuit contains ideal operational amplifier, Vs voltage is sinusoidal with amplitude of 1Volt and frequency of 1kHz, where VE is a dc voltage of 2Volts.
I am trying to use ...
3
votes
2answers
1k views
0 to 2A variable current source circuit
I'm trying to build a 0 to 2A variable current source following the Linear app note.
Here's the schematic:
The circuit is a difference amplifier (LT1995) providing gain to the voltage developed ...
3
votes
2answers
5k views
Connecting Switches to Hidden Supply Pins in Proteus ISIS
I am currently working on a simple circuit involving logic gates in Proteus ISIS from Labcenter. By default, the power pins are hidden. You can access them by right-clicking the component, selecting ...
2
votes
1answer
197 views
Maximum current, maximum voltage
Given that 0 <= R <= ∞ in the circuit shown, consider these two observations:
Observation 1: When \$R = 2\Omega\$ then \$v_R = 4V\$ and \$i_R = 2A\$.
Observation 2: When \$R = ...
1
vote
2answers
273 views
0-12V Adjustable Home Made DC Source not working [closed]
I have a home made dc source that is made a few years ago. Solders at the back of the board are very bad so I can not track the connections very good. But it's circuit diagram is very similar to the ...
0
votes
1answer
119 views
Expressing the current through a dependent voltage source
Consider the circuit below:
The task is to find the node voltages V1, V2 and V3 (labelled 1, 2 and 3 above). In order to solve the problem I apply the node voltage method; summing all the currents ...
0
votes
1answer
105 views
Calculating currents with a current source in series
Is this circuit correct? I am not sure if I can consider I5 as a current source. I remember that current sources cannot be in series.
Or is this as easy as it looks. Specifically I am getting ...
0
votes
2answers
70 views
Current and voltage sources
What happens when a current source is connected in series with a voltage source? I mean to ask, what will the current be through the series combination and voltage across it?
Is it allowed to make ...
4
votes
2answers
838 views
Logic gate using current source and diodes
This circuit is supposed to work as a logic gate. I need to find out the logic operation it performs. Suppose the diodes are ideal.
https://www.circuitlab.com/circuit/egg3wh/logicgate/
...
0
votes
1answer
346 views
Low voltage/current power supply for wide range of inputs
I was thinking of simple low voltage/current power supply that can accept wide range of input voltages, up to the hundreds. Let's say, the input is 20 to 160V DC and output has to be 10V with 20ma ...
2
votes
1answer
368 views
current controlled current source
Objective
I am trying to build a gain-of-1 current controlled current source (current mirror) that is less sensitive to resistor value variation. The designs i have been making are highly resister ...
4
votes
2answers
1k views
Driving Relay Board with Shift Register (Shift vs Sink)
I am trying to drive some ebay bought 8 channel relay boards. They are pretty simple, have a launchpad or arduino toggle a pin and the board turns on. However, I need to use a shift register with ...
0
votes
3answers
679 views
Use transistor to auto swap power source
Basically I'm looking to use a simple transistor circuit to diconnect one V+ (or ground) when another is connected and automatically switch back when the switching source is removed.
Like having a ...
5
votes
3answers
828 views
Purpose of these two transistors
Hi does anybody know what's the purpose of the Q1 and Q2 transistors,
sounds to me like they are constant current sources. Am I wrong?
Could somebody explain me the purpose of those Q1 and Q2 ...
2
votes
1answer
467 views
Converting a battery powered pocket heater into a portable 5V power source
I bought the attached pocket heater. The elevated element seems to be heater spirals so the red cables seem to lead to short circuit - capable circuitry.
Background: So I built this tight case for ...
5
votes
3answers
312 views
Capacitor discharge and 1/2 terminal voltage sources
I understand that this is really basics of electronics, but I would really appreciate if somebody clearly explained following question.
So here is a small set of questions related to similar topic:
...
4
votes
1answer
271 views
Understanding a transistor configuration
I started watching this video series on a DIY lab power supply by Dave @ EEVBlog.
On his video he's analyzing mostly simple constant current circuit. However, at the top of the circuit there's two ...
1
vote
2answers
764 views
Current source with pulse option
I am seeking a very fast (10nsec rise time) transistor based fixed current source that I can use with my CPU. The CPU will use the GPIO to turn on or off the current source.
This will be used to ...
