Questions tagged [analog]
Analog circuits have a range of voltages, rather than just two as in digital logic.
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Analog Circuit Modelling in Simscape (Simulink) doesn't work (No Input sighted)
I tried rebuilding the analog circuit for the Lorenz Attractor in Simulink using Simscape toolbox. Luckily they have also an analog multiplier circuit built-in and I re-wired everything just as the ...
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Is it okay to split the same net to sample an analog signal in two ADCs?
I have an analog signal that comes from another place with a range of 0-1 V, the required resolution should be 10 bit.
I want to sample the same signal in two ADCs, the internal ADC of the STM32, and ...
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Differential vs. single-ended A/D input range
ADC data sheets (one example below) state that the differential input of A/D can span between -Vref to +Vref. Yet when it's single ended it only spans 0 to +Vref.
If a differential input can swing ...
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LTspice voltage measurement
How do I measure voltage between two nodes when neither of them is ground? In the schematic below, I want to measure the voltage between nodes Vmic and Vx. Is it just (Vmic-Vx)? I'm afraid that gives ...
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What is the difference between adding capacitor in 2 different ways to create the delay?
I’m finding similar delay results for both the circuits shown below.
Draft 1: Capacitor C3 and C1 are connected to separate branches, though both of them together determine effective delay.
Draft 2: ...
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Wien bridge oscillator problem
I am running into a problem trying to set up a Wien Bridge oscillator on a breadboard.
It works well in the simulation:
In practice, though, I get this waveform:
Does anyone have an idea what could ...
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How can an analog multimeter have a combined mV and µA scale?
Looking at analog multimeters on Amazon I came across several that have one switch position that appears combined for the lowest V and µA settings. I've used various analog multimeters over many years ...
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Using 0-3 V sensor with 0-10 V PLC
I have a sensor that generates an analog 0-3 V output signal. I would like to connect this sensor to a PLC which has only 0-10 V analog inputs.
My questions are:
Is this recommended to do in general? ...
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Why is this happening using Multisim?
I'm using the website https://www.multisim.com/create/
Why does Multisim show the current as negative above the Zener diode?
Both probes are going the same way, yet the current is shown as a negative -...
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What’s the simplest way to switch between 2 analog signals when one of them goes above a specific voltage?
I need to connect 2 analog signals to the same output, one signal at a time. One of the signals goes through a potentiometer and sits between 0.3V-5V. What is the simplest way to switch that analog ...
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Using SN74LVC245AN for 5V to 3v3 serial data translation is causing input to not go to 0V
Integrating a ESP32 with a device which outputs 5V serial signal. This is a device I have no control over and don't know much about (ie: CMOS vs TTL, etc?). All I know is that it has a 5V serial ...
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Transferring maximum power to multiplexed loads
I'm interested in creating a system driving 8 different loads from a single amplifier, at relatively high currents of few hundred mA
I wish to do this utilising a 8:1 multiplexer IC (8* spst), where ...
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DC Analysis of Common Collector Circuit with current source at emitter
For the circuit below I have to derive IB, R1 and R2
Since it is a DC-analysis, I turn the AC-sources off and make the capacitors open circuits. So the circuit becomes the following
IB is straight ...
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Breadboard contact resistance
My question is about breadboards. I've been using breadboards for 5 years and even if they are good only for early prototypes and are not too reliable, they have always let me build what I had in mind ...
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Version control with MultiSim
I am a beginner with analog electrical circuits. Similar to computer programming and CAD, is it recommended to use version control software when working with MultiSim? Are there circuits complicated ...
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Why does the LM1881 make an odd/even signal even with progressive inputs?
I noticed that when I apply a 720p or higher signal to an LM1881, the odd/even pin outputs a square wave signal which it shouldn't. On 240p it doesn't, as expected.
Did I miss something? My input is ...
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12 VDC power supply with automatic detection and switching
I am trying to run a solar system that will be used to power ~30 lights when the mains power is off. I'm running an AC-DC converter from the mains to get 12 V and this will power the lights when the ...
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LM1881 noise at CSync output when not connected to anything
Im trying to get CSync and VSync out of an composite video signal. This is my schematic:
It's the same circuit as in the documention of the LM1881. In general it works well, but I noticed something: ...
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Algorithm for impedance calculation from known I and V sinusoids, L and C unknown
I am trying to extract the impedance from a sampled signal. Specifically, I have only noisy samples of a sinusoid, of a single period, of current and voltage at a given known frequency. I am trying to ...
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Triangle wave to sine wave conversion: no output
I am trying to replicate the following waveshaping schematic:
I've tested my version in LTspice and it seems to work fine (I've tried to make use of the one unused op-amp and created an inverse ...
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How do I get a 1.5 V reference voltage from a 3 V coin cell battery? [duplicate]
My goal is to build an amplification circuit powered by a 3 V coin cell battery that uses an instrumentation amplifier to read a differential voltage.
The instrumentation amplifier chip has a ...
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How to charge multiple High Voltage Li-ion Batteries
I want to charge six DC 80v/30A lithium ion battery with BMS using single phase power DC supply source.
Batteries need (6*2.4 kWh. Charge efficiency about .8:) 18kW roughly power.
Power Source has ...
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Active notch filter behaves like a low-pass filter
I'm trying to build an active notch filter centered at 50 Hz. I'm trying to wire it using a breadboard but I'm facing some problems with the output signal.
Before wiring the circuit, I tried to ...
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ESP8266 analogRead() microphone input into playable audio
My goal is to record audio using an electret microphone hooked to an analog pin of an ESP8266 (12E) and then be able to play this audio on another device. This is my circuit:
In order to check the ...
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Garland control circuit broke down
The garland is 220 V and consists of two series of 96 LEDs each. The LEDs are warm white, medium brightness, the current is unknown, perhaps about 20 mA. It will be enough to have a circuit without a ...
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In an RC circuit, how do you explain the fast rise of voltage at a point close to source? (Weak pull up)
In the above figure, the voltage at the intermediate point rises quickly whereas the voltage after R2 is increases slowly ( as governed by the capacitor voltage.)
I am not getting the intuitive ...
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Doubt about grounding loop and shielding
Good morning,
first at all I want excuse me for my english and my inexperience.
I have working with complex setup (osciloscope+SMU+Waveform generator+ some circuits and shielding cage) and now Im ...
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Can I use the Analog pins on Arduino micro as digital pins? [duplicate]
Can I use the Analog pins on Arduino Micro as digital pins? if Yes are there any Analog pins I cant use as digital pins on the Arduino micro?
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Cancelling optocoupler pole in an isolated voltage mode controlled smps
I am designing a 600W halfbridge converter with a voltage mode controller(TL494). I am using a type 3 compensator with TL431 as shown in the image below:
where:
The capacitor C2 constitutes the ...
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Parallel Resonance for Wireless Power Transfer
I have two 50 uH coils. I'm using a 68 nF capacitor for each the primary and secondary coils. This puts the resonance frequency to about 86.313 KHz. The primary coil is in series with the 68 nF ...
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Diode voltage drop characteristics in an envelope generator design for audio synthesis
I have no actual EE knowledge, I have just been fiddling around with audio circuits for a while.
I built an attack-decay envelope generator for audio synthesis purposes following a design by Ray ...
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Can I use the analog pins on an Arduino as digital pins?
I need more digital pins on an Arduino. Is it possible that I can use analog pins on the Arduino as digital pins?
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Resonance Frequency Drift
I'm working on a wireless power transfer project. The coils that I'm using are made out of Litz wire with a value of 50 uH. For the capacitors, I'm using 68 nF capacitors. This puts the resonance ...
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Unexpected output from LC circuit
I am trying to get back into some electrical engineering basics, and had a quick question regarding an unexpected output I am seeing. I am trying to learn about RLC circuits again, and wanted to build ...
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How to measure signal with ADC from position sensor 5 meters away?
I want to design a new board that includes an ADC (AD7606C-4) and STM32.
I need to measure 3 analog signals from a position sensor (PDP90A).
The distamce of the position sensor from the A2D is ~5 ...
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Noisy ADC sampling on NUCLEO-F070RB
I built a circuit on a perf board, see schematic below. Basically, I have an analog sensor where the output is a Wheatstone bridge. I connect this to an instrumental amplifier (AD623ANZ) with a gain ...
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Unexpected voltage shift on analog input
I have a resistor divider analog input circuit that has an off-board resistance applied in the form of a sensor. The off-board sensor/resistance can be anywhere from 300 Ω to 12 kΩ.
I see strange ...
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Widening MOS device leads to subthreshold conduction
Could someone explain why increasing the W/L (hence g_m) would lead to the device eventually going into sub-threshold. I thought by increasing W/L, the current would increase, so we would be further ...
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Stereo Speaker System - Design Recommendations?
I found that I have two TDA7377A Class AB Audio Amps, and since I got to electronics I always wanted to make my dream amplifier.
My idea is to make a 2 part system, where the first part is the main ...
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RC-OTA versus gm-C integrator in CT Delta-Sigma
In the book "Understanding Delta-Sigma Converters" of S. Pavan, R. Schreier and G. Temes they are stating the following speed comparison of the RC-OTA and gm-C integrator:
The impressive ...
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Does the impulse response of a system include both its transient response and steady state response?
Suppose you connect a circuit containing passive elements like resistors, inductors and capacitors to a voltage source. Now you provide an impulse to the circuit. Is the response by the circuit the ...
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Does an AC voltage source introduce transients in the circuit?
For past several days, I have been struggling with a concept. Suppose you connect an AC voltage source in series with resistor and capacitor. As the magnitude of the voltage source is changing ...
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50 Ohm-Terminated Antenna Oscilloscope Readings
As a follow up to my previous question about measuring antenna performance via amplitude at 88 MHz to 108 MHz on a DSOX1102G oscilloscope, can I trust these new readings? Measurement channel is on 1:1 ...
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Comparator with linear output to equalize inputs [closed]
I am a ME dabbling in some EE projects so forgive me if this sounds clueless! I am developing a current feedback system for a power supply.
I am looking for an analog device that will adjust the ...
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Probing 50 Ω antenna output with oscilloscope
I would like to see the signals that I am picking up and I have a DSOX1102G oscilloscope. My probe has a switch that says 10x and 1x.
I have built a 1/4 wave VHF monopole antenna out of a SO239 ...
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Source follower input/output swing
I found in this book at the page 271 a definition of the source follower input/output swing ( that i didn`t know as:
$$ V_{in-pp} = V_{dd} - ( Vt + 2.V_{ds-sat} )$$
I tried to understand how to ...
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Trying to compute the sound pressure level in dB of a signal
I'm trying to develop what's shown in the image below.
I already have everything developed and tested till the last amplifier that connects to the ADC, I see no point in it.
The signal that leaves ...
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How come I'm not getting the same output at the EAout, with the unity-gain buffer EAOUT output follows the +IN input
The EAout pin does not output the same signal as +IN, the signal is coming from a voltage divider after full bridge rectification
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How does this constant current circuit work?
I'm trying to develop a constant current source capable of outputting 10mA regardless of impedance changes. While I was looking into improved howland pumps as a potential solution, I came across this ...
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Effects of coax length in a 50 ohm/ 75 ohm mismatch
I am building a broadcast FM receiver (88MHz to 108MHz).
My antenna is a 1/4 monopole with 4 quarter wave radials and has an impedance (Zsource) of 50 ohms.
I am connecting it to a 75 ohm rg6 coax ...
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