Questions tagged [analog]
Analog circuits have a range of voltages, rather than just two as in digital logic.
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Power combiner for I-Q signals in a transmitter
I have a transmitter project to implement. Part of the project is to combine an in-phase and an out of phase (90 degree difference) signal with a center frequency at 3.5GHz. I figured I could ...
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Simple Diode Mixer Help
Edit:
Thank you for your input @Kevin White, much better results with 100 ohm injection resistors, a 1K resistor for a DC pathway and a 1K bias resistor from Anode to +5V.
I am an RF enthusiast that ...
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MPQ3904 LTSPICE Model
I'm trying to do some LTSPICE simulations using a MPQ3904 NPN BJT. Of course this specific model is not in the LTSPICE library. I tried to look up possible models online but I can't find anything.
The ...
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Low Side Parallel MOSFET Drive [closed]
I'm doing a 12V to 230V push pull inverter design & need to drive it via two MOSFETs for each transformer tapping. Mosfets feeds by an optocoupler PC817. The frequency is 50Hz coming from a PIC ...
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How to convert the outputs from the AD8232 ECG modules back to the raw ECG millivolts (mV)
I have been working with the AD8232 ECG modules for a while now and I am trying to figure out what the raw ECG outputs from this module correlate to. I cannot seem to find any information from their ...
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Amplifier with selectable inversion?
Two inputs:
Signal: 0-5 volt analog voltage
Direction: Standard TTL logic
Output: A single analog voltage from -10 to +10 volts
When Direction is low, the Signal is amplified and inverted, so that ...
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TVP5150 output 0x80,0x10 and input video signal not locked
This is my first question, I hope everything is ok :)
I have been struggling with a problem for a while now. I have a PAL camera (from which I barely have any information) connected to a TVP5150AM1 IC ...
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LTspice JFET Voltage Divider Bias Configuration
I want to simulate this circuit in LTspice program and find Idss,Vp and Idsq,Vdsq but cannot. How can i simulate transfer characteristic?
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Momentary switch to activate 555 timer
I am very new to circuits and I've tried everything online but nothing seems to be working. I am making this circuit for a class.
I am trying to emulate this circuit diagram from this youtube video ...
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Analog to digital conversion for neural network weights
I am a machine learning researcher, and lately I am getting interested in neural networks trained on analog hardware. However, I have some doubts about their potential, probably because I am missing ...
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Cascode: Which device goes into triode region first?
In the above cascode network, which device goes into triode region first, if the supply gradually decreases?
Framing the question other way round, if the supply gradually increases from 0V, which ...
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Decoding VGA Signals on a microcontroller design concerns
I have a microblometer sensor that outputs a VGA signal with resolution 640 * 480 pixels. Lets say I want 30 FPS..
I would like to know what would be the easiest way to convert that video signal into ...
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How to transform resistance between two linear ranges?
This question is motivated by an automotive problem from this question.
In a quad vehicle, in a 12V system, there's a fuel sender with 0-100 ohm range, empty to full. The fuel sender was a part of a ...
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How do I connect a female EEG electrode to a breadboard?
Electrode output end:
EEG electrode:
I'm trying to connect the output of EEG electrodes to a breadboard as input. How do I connect the electrode to the breadboard? Usual jumper wires don't seem to ...
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iCE40LP1K FPGA - Performing an analog to digital function (Power monitoring) without an ADC
I'm using iCE40LP1K FPGA and I wanted to create a block that is responsible for doing a fast power down of all devices on the platform when the 12V is shut down due to powercut.
Whcih means, when 12V ...
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How can you turn perceived brightness (log scale) into a linear analog output using an LDR?
This question is not about how to make illuminance (in lux) a linear function of voltage!
It's about linearly representing the human perception of brightness, which itself scales logarithmic to the ...
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Phasor analysis confusion in the trignometric identities
I was learning about phasor analysis from Fundamentals of electric circuits by Alexander and Sadiku.
In chapter 9 the below trigonometric identity is given.
As per my knowledge sin is positive in the ...
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Compare two voltages and output the higher of those two
From the LM35 output I get from 0V to 1.5V. There are 4 outputs like this.
How can I compare these values without using a micro-controller and forward the highest value of those 4.
I can't connect the ...
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Non volatile memory on simple hardware board [duplicate]
I'm designing a low frequency board with some analog signals inputs and a few discrete logic gates which drive warning LEDs. I want to save the status of the LED even if the board is powered off. No ...
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How to convert hydraulic pressure gauge into analog output?
Below is the pressure gauge of the heavy equipment. The pressure gauge needle is moved by a hydraulic pressure line.
We are looking to capture the hydraulic pressure into an IoT device that takes an ...
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High side MOSFET gate driver for pure DC application (non PWM)
I want to drive a highside MOSFET which is supposed to be on for hours.
I tried TI's approach of using a 555 timer and IR2110 but from my simulation on LTspice, the outputs at the HO pin of the ...
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Level shifting of a 3 state pin
I want to design a simple battery charger using MCP73831/2. This chip has a 3-State state pin according to the table below:
I have a 3.3V MCU and I want to connect this pin to a GPIO. The MCU is not ...
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How can I match the impedance in the distributed transmission line model?
I'm trying to do impedance matching for an inverter transmitting signal through a transmission line in Cadence. The transmission line is modelled as a number of RLC elements(\$R_{TL}=0.1\Omega\$,\$L_{...
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How should I go about overriding or switching between an internal control voltage source when an external source gets connected?
For example, I'm using a potentiometer to modulate an internally generated +5v audio signal, and I'm sending the output signal down to the next part of my circuit. If I were to add an external input ...
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Figure of Merit for sizing P-MOS and N-MOS in Inverter circuit
I am trying to design a basic circuit block of inverter (Analog circuit) in Cadence Virtuoso schematic in 22nm technology. It will be used for non-overlapping clock generator. I need to size the P-MOS ...
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How to add unit function u(t) - u(t-2) as voltage source in LTSpice?
As far as I know, we put the unit function as PULSE in LTSpice. If we have b.u(t) where b is a non zero integer, then we can put it in Von. But what if the function is u(t)-u(t-2)? And what if we want ...
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No current changes using INA219 to reading industrial sensor
I intended to use the INA219 chip to read the 4-20 mA current loop of the industrial sensor for the automation project. the sensor voltage is 12 V, my first schematic was as follows:
The ground of ...
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Start-up problem and current consumption of transistor circuit
I am trying to optimize a thermal detection circuit. But there are several problems.
The circuit for detecting 85 Celcius temperature and then disabled a PWM IC. When the FB pin is below 0.5V, IC is ...
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How to control multiple current paths from one physical switch?
I am working on a college project for my Analog Electronics class as part of my music technology class. I want to create a synthesizer where buttons can control Rf to change the oscillators frequency, ...
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Band pass filter with single-supply op-amp not filtering
I am working on a university project that requires me to build a 40kHz band pass filter for receiving an ultrasonic signal.
The filter is to be implemented into a portable device powered by a 9V PP3 ...
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Analog sound data
I tried to make my own sound sensor on a PCB. I wanted to take analog sound data for my project. I used an ADC pin from a STM32G474, but I maded mistake while I designing. I took a KY-038 reference ...
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How to connect a 2 wire current sensor to a 3-wire set-up?
At the moment I have a couple of 3 wire current(4-20mA) sensors inside my setup that have the same connection as the schematic below.
One of the sensors has broken. We can not directly get the same ...
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Why choose pmos over nmos
In the attached schematic, there are two branches. The branch on the left has a pmos + nmos transistor. The branch on the right has two nmos transistors. The sizes of the devices were selected such ...
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What are "dummy terminals"
This picture is in datasheet of one relay:
From this picture I assume that if there's current flow between 1 and 8 pins, the relay will connect 3 and 4, right? What are "dummy terminals"? ...
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noise based dimming of an LED
I am thinking about building a dimmer for an LED that does not use PWM. My idea is to use a white-noise-signal and switch an LED on (or off) depending on whether the signal is above or below a certain ...
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Resistance averaging circuit / resistance divider circuit (NOT voltage divider)
I'm trying to design a circuit to average 3 Pt100 resistors to feed into a single temperature controller.
All the solutions I've found so far involve either a microcontroller or a complex opamp + ...
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Characterizing "quadratic current" in an NMOS
I'm designing an integrated circuit where a series of NMOS with their sources tied to GND and their drains tied together work as parallel current sources. The total added current \$I_D\$ that I'd like ...
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Adafruit Feather reading analog data incorrectly
I have some dead simple code for reading the x and y analog values from my Arduino joystick module. It works fine on my Arduino Mega 2560, but Adafruit Feather nRF52832 reads the analog signal ...
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Is chopping used for the the most precise voltmeters?
Are the most precise nanovoltmeters (e.g., Keithley 2182A) for 1 Hz sampling (i.e.,
measuring the average over each second) chopping the input stage?
I can't tell from datasheets and am curious how ...
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How to choose component values in a current drive circuit for solenoid?
I've designed a current drive circuit for a solenoid using a DAC and a MOSFET push-pull setup with feedback based off Figure 4 and 5 in this application note (https://www.analog.com/media/en/technical-...
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Voltage measurement using an opamp
I am trying to do the circuit analysis of the following circuit using LTspice.
When Vbatt crosses 5 V (switch is off all the time,) the output voltage is nearly constant at 0.931V. What causes the ...
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Datasheets, dimensioning questions
I have a problem reading this datasheet.
This one is very weird, does 3-1.5 mean that pin is 3 mm wide, and 1.5 mm is meant to be a radius, or does it mean 1.5 mm and that that 3 means three pins?
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Why is my amplifier motorboating?
I have been trying to make a simple guitar amplifier and I've been having a lot of trouble trying to get it to work properly. It keeps on motorboating at a very low frequency which is driving me nuts. ...
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How to switch between two voltage sources?
I'm trying to design a circuit to switch a voltage source between 12V and 24V for a load that draws 400mA. Initially I thought I could use a SPDT analog switch but the ones that can tolerate >24V ...
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ADC and RC filter importance
TI and ADI suggest using an RC filter, ADI noted that SAR ADC have switching kickback and say it's really important but STmicroelectronic says the components of the RC filter discussed in the TI and ...
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Buying a variable inductor
I need a variable inductor of about 70 nH. I found one at Mouser.
As you can see, it says that its inductance is 70 nH, but when I open the datasheet it says that inductance is from 9 to over 280 nH. ...
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Measuring 3-phase voltage up to 480V using Arduino/ADC
In order to calculate true RMS phase-phase voltage of a 3-phase delta 3-wire industrial utility, I have been using Zettler Magnetics AHI02516 as step-down/isolation transformers, along with some ...
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Analog pins showing incorrect data. Only from 0 to 255
A month ago, I connected a joystick with an Arduino Uno. VCC with Arduino 5v, GND with ground and Y axis with analog. I tried all, but the error persist with all 6.
A month ago, in the serial monitor ...
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Designing a 500 mW audio amplifier
I have to design an audio amplifier to drive 500 mW 8 ohm load. I used two SMD transistors (BCP54 NPN and BCP51 PNP) and three BC847Bs, one to drive the BCP transistors, one for voltage gain, and one ...
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