All Questions
172,722
questions
0
votes
1
answer
36
views
Transient analysis for circuits with AC excitation using differential equations
In the process of finding transient response for circuits with AC excitation using differential equations, we use the method of complementary functions and particular solution, but I read earlier that ...
-3
votes
1
answer
62
views
DC-DC Converter voltage drop on load [closed]
I bought a DC-DC converter to charge my devices with the 20V 1Amp current of my solar panel. I set it so it would convert to 5V but when I connect to load the voltage drops to 4.7V or less depending ...
0
votes
0
answers
25
views
Measuring PoE power consumption with an oscope: Is PoE Ethernet non-grounded?
I have a need for measuring current (and thus power) delivered via Power over Ethernet. I have created a modified Ethernet cable by splicing shunt resistors into it already, but I'm unsure about the ...
- 1,010
2
votes
1
answer
124
views
Which variant of amplifier to use?
I am making a pressure sensor circuit according to page ten of the manual here. There are just too many types of the recommended sensor LMV324 available in the SOIC type. Can someone help me decide ...
- 69
0
votes
2
answers
93
views
How does one convert DC to AC in context of playing audio?
I'm working on a little gadget. A simple two button mini game with a simple oled i2c display. I wanted to add sound and a bit of music. Nothing too fancy, mainly drums using white noise and two or ...
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-4
votes
0
answers
40
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Where is bios stored in MSI GF63 THIN 9SC laptop? [closed]
I have wanted to know in which component the bios of my laptop is stored, but I cannot identify where it is stored.
I have read that in newer laptops the configuration is stored in eeprom memories and ...
0
votes
0
answers
18
views
Difference between Harmonic Balance and Transient solver in ADS
I am performing a simulation of a half wave rectifier (HWR) in ADS. I had developed a MATLAB code for Harmonic balance solver and Transient solver in MATLAB. The code gives comparable results when ...
- 61
0
votes
2
answers
28
views
Does a Marx generator work good with low frequency?
If it rectifies AC to DC it still has ripple frequency. For a Marx generator, should that ripple frequency be high or will it still work with low frequency? On, YouTube the flyback transformers ...
- 55
0
votes
0
answers
78
views
PCB panel design
I am designing a 4-Layer 0.5mm thickness PCB.
The outline is rather small which introduces some problems with panelizing the PCB. As I am a novice regarding these topics I would like to ask for help.
...
-1
votes
0
answers
19
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What is the requirement of 2.5V to CT pin? [closed]
My question is related to the following question:
Connecting Transformer to Ethernet PHY
Can you comment on the requirement of 2.5V power to the CT pin RJ45 connector?
- 307
0
votes
1
answer
81
views
How is this possible: Crystal filters for FM signals?
I am trying to make my own superhet reciever. I have achieved downconversion and I am trying to build a crystal filter that will only allow the crystal's resonant frequency through. In doing so, I had ...
- 151
1
vote
0
answers
51
views
PCB 0402/TQFN pad design
I am currently designing a product which uses 0402 passives and other fine-pitch parts. As the PCB-space required is a major design goal I want to reduce the footprints. High production yield is also ...
0
votes
1
answer
34
views
Using transformer secondaries for audio amp
I have a old XFR out of a audio amp and want to repurpose it for another DIY amp project using the lm3876. There is a 5 pin connector for the secondaries, I checked voltage potentials across all 5 ...
- 1
0
votes
0
answers
48
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MAX 32660 Schematic Questions
I do have some questions regarding the MAX32660 MCU from MAXIM.
See the documentation:
User Guide Datasheet
1. RTC-Pins: For routing purposes I would like to connect the 32KIN/OUT ports to GND. I do ...
-3
votes
0
answers
29
views
Where can I buy mini cameras with the zoom in feature? [closed]
I'm looking for a mini camera (smaller than the palm and lightweight) which supports zooming in within the app.
As I'm a beginner to electronics, I'm unsure about what terms to search. I've searched ...
0
votes
0
answers
16
views
Antenna port S11(dB) > 0
I'm simulating a microstrip patch antenna in microwave office at 35 GHz.
When plotting the S11 in dB of the antenna port I get values greater than zero at frequencies below 28 GHz. How is this ...
- 1
0
votes
1
answer
52
views
Ultrasonic phased array speaker spacing for high directivity and efficiency
(Short version of question(s) below.)
I want to make an ultrasonic parametric speaker at 40kHz, I want to drive them all at the same constant frequency to keep the electronics cheap.
When simulating ...
- 133
0
votes
1
answer
58
views
How to control current to charge batteries?
I have an Arduino project that is powered with a 1s battery pack (multiple 18650 in parallel).
I use following module to protect against overcharge/overdischarge : https://aliexpress.com/item/...
- 296
0
votes
0
answers
54
views
Wirelessly measuring voltage between two points? [closed]
I would like to measure a voltage between two points, wirelessly, but am stuck on the need to have physical contact between two points to be able to get a voltage reading...
So I would like to be able ...
2
votes
3
answers
126
views
What is the purpose of the parallel resistor at the end of this amplifier circuit?
I have this following circuit that I tried to decompose and find the purpose of each component.
The op amp is LM6181 and the purpose of the circuit is to reduce the voltage of a probe so it fits ...
0
votes
0
answers
17
views
Lavet type stepper motors design guidelines
For a client we need to provide a Lavet-type stepper motor - I'm looking for some design guidelines - there seems to be very little technical literature on this type of motor.
Wikipedia seems to be it
...
0
votes
0
answers
35
views
Reactive power fluctuation
We have 6 Caterpillar gas generators 3520c.
One of them when synches with the grid. Its kVAR fluctuates over wide range and the aux voltage too and the excitation volt and current. We checked AVR and ...
0
votes
2
answers
71
views
How many loads can I have on an open drain output?
So I am using this AND gate which has an open drain output. I am trying to determine how many loads that I can place on this output.
I see in the datasheet, that the Iol is over 1mA, but I am unsure ...
- 111
0
votes
0
answers
62
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Thevenin's theorem for Voltage divider bias
I am calculating the base current of transistor Q1. To simplify the circuit equations, I applied the Thevenin's theorem and converter V1 and R1, R2 into Vth and Rth as shown in the image.
Vth= V1x(R2/...
2
votes
4
answers
578
views
Is the resistive component of impedance the same as DC resistance for a given component?
If I calculate the impedance of a component in an AC circuit as Z=V/I, will the resistance component of that impedance, ZcosΦ, be the same as the resistance when that same component is in a DC circuit ...
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-1
votes
0
answers
44
views
What is the technical term for a transparent monitor which is visible on only 1 side? [closed]
What is the technical term for a transparent monitor which is visible on only 1 side?
For example, if you had an OLED monitor where you can only see the screen from one side
A bit like what would be ...
- 1
-7
votes
0
answers
29
views
Using The Microphone in slot as antenna [closed]
I bought A system that has no place for antenna..FM reception is not all that.. Can I use the microphone in slot as a antenna. Was wondering if I use a 6.35 adapter and plug a antenna with a 3.5 jack ...
0
votes
1
answer
55
views
How much current can I *really* draw out of a 5V up-to-20A buck converter connected to a 12V10A DC supply powering both the buck and a 12v load?
first of all I'm a hobbyist so it's ok to roast me provided it comes with good insights!
I am prototyping an electronic apparatus comprised of different parts
a microcontroller running on 5V (...
- 11
0
votes
1
answer
36
views
Do I need a current limiting resistor with an industrial rail DIN optocoupler?
I'm going to use this industrial opto-coupler:
Optocoupleur RS PRO, montage Rail DIN, 6 mA
In its specs document they don't mention the need of a current limiting resistor. I always add a current ...
- 245
0
votes
2
answers
58
views
Control 12V relay by using Arduino [closed]
I have an Arduino Mega, 12V relay module, and 12V external power supply.
I want to control relay state (on/off) by using Arduino I/O pins (5V).
Is it good idea to use following simple diagram?
There ...
- 111
4
votes
3
answers
785
views
Quartus Can't fit design into Device, is there any way to optimize it to get it to fit?
I have a module that takes in a sample, puts it in a large buffer, and sums the buffer. When it synthesizes, Quartus says it requires too many combinational nodes. I tried many things to see what ...
- 51
4
votes
2
answers
518
views
Confusion In RC circuit
I want to calculate voltage across the resistor.
I divided the circuit into two parts:
Charging=0<t<1, 2<t<3, 5<t<6(ms)...
Discharging=1<t<2,4<t<5,7<t<8(ms)...
$$...
- 65
3
votes
1
answer
138
views
Difference between open drain and push-pull modes
The figures show diagrams of line signals: the first in the open-drain + pull up mode, the second push-pull + pull-down.
There are several questions:
Why does a push pull output have a faster slope ...
- 43
-3
votes
0
answers
89
views
Using a microphone in place of an antenna [closed]
Can I use a microphone in place of an antenna? The piece I bought has no antenna and the FM reception is not there. Would use a 6.35 adapter and insert a 3.5 antenna in to the adapter. It is a nice ...
1
vote
0
answers
56
views
How to draw AC equivalent circuit for low cut-off frequency?
I have the following circuit with me and I wish to draw AC equivalent circuit for low cut-off frequency to determine the dominant low cut-off frequency. I am confused, especially for the capacitor C3 ...
-1
votes
0
answers
43
views
Dynamic routing how devices find their position in the network [closed]
Suppose we have a network of routers A , B , C , D and none of A,B,C,D know where they are in the network,they dont know how many neighbours they have or what is the delay between themselves and ...
- 467
1
vote
2
answers
69
views
Supply voltage for opamp in a current sink circuit
I want to use an opamp in a current sink configuration in order to control the emitter-base current of a PNP transistor via a digital-analog pin from a microcontroller.
The circuit is as shown below.
...
- 111
0
votes
0
answers
39
views
DRAM Refresh Time
I am trying to understand, how can I calculate the refresh time of DRAM, if I consider that as my memory requirement, that I need is 32 DRAM chip of 1M * 1bit each to get 4MB Memory capacity. Each ...
-2
votes
0
answers
41
views
Combining audio signals without backfeeding the original signal
I'm building Audio tracks looper on Raspberry Pi, which records audio signal from Keyboard / Guitar (Jack plug) and plays it along with the original input on headphones.
but this scheme is faulty, I ...
- 1
0
votes
1
answer
67
views
Hamming code question
Suppose we have m data bits and n parity bits. In order for the Hamming code to function: $$m+n<2^n-1$$
If we have 3 parity bits we can have up to 4 data bits. But lets say we don't have 4 data ...
- 467
0
votes
1
answer
36
views
What does power balance and voltage balance of a circuit tell? How to calculate them? [closed]
What information does power balance and voltage balance of an electrical circuit give about that circuit? What is the general procedure to calculate them? Are there any automated tools in which we ...
- 9
0
votes
4
answers
112
views
What happens if a 12V battery is constantly exposed to a 12V power supply?
If a 12 volt battery is exposed to 12 volts for a long time would it overcharge the battery and harm it, or would the battery be unaffected, and not charge at all since there is no "additional&...
- 127
0
votes
1
answer
87
views
Impedance matching between 93 ohm and 50 ohm
I have a detector of an unusual impedance of 93 ohm connecting to a digitizer of 50 ohm through a coaxial cable of 50 ohm. Unfortunately I can not change the impedance setting of my digitizer.
...
- 25
-1
votes
1
answer
62
views
ATmega freezes because of power supply
I'm using a 10W/12V PCB mount SMPS for a project. In the same board I'm using an ATMEGA2560. When there is a power fluctuation, the ATmega freezes and all the communication is halted. How can I fix ...
- 1
0
votes
0
answers
55
views
Verilog state machine, state does not change [closed]
Below is my code in which i want to shift the data serially out from the FPGA in state "transfer".
However when I simulate it, the state does not update. It is stuck in "update state.&...
2
votes
0
answers
77
views
STM32 - I²C Slave HAL Callback ACK
Objective: implement a single byte I²C slave on STM32.
Materials: STM32L452RE Nucleo-64 board, HAL Library, CH341 USB-I²C adapter(1), Artix Linux with Runit, Rhode & Schwarz RTB2004 oscilloscope
...
- 21
18
votes
2
answers
1k
views
Identify this type of diode from the 1970s (1.3V forward)?
I am currently reverse engineering the electronics of a Pentax Electro Spotmatic camera from the early 1970s. I have the circuit mostly figured out but now I want to find out more about the particular ...
- 183
-1
votes
0
answers
19
views
Electret microphone application circuit (AOM-5024L-HD-F-R)
I want to design a microphone circuit with an electret microphone. I am a noob working with audio circuits. I would like to know how I set the values of the R and C in the application circuit for the ...
-2
votes
0
answers
15
views
How do I set the maximum iterations in the built in particle swarm optimization method available in MATLAB [closed]
I've used the 'MaxIterations' command available in optimoptions method but the algorithm is exceeding the maximum iteration count to reach the optimal value of my specific function. I want to know the ...
- 1
0
votes
1
answer
38
views
STM32H7 External supply
I'm using STM32H750VBT6 and my template code is generated by CubeMX. I don't use external RCC but low speed clock crystal.
In CubeMX at RCC I clicked on parameter settings tab. I then changed the ...
- 23