Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [vf-fv-converter]

12 questions
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How do I use pin5 to control duty cycle of a 555 based PWM?

I have built a simple PWM using a 555 IC to drive a motor for an optical chopper and I want to be able to use the output of the chopper signal as a speed correction feedback for the PWM. I think I should be able to do this using pin 5 on the 555…
Jonathan
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Frequency-To-Voltage Convertor With LM2917

I'm trying to make a frequency-to-voltage converter by using LM2917. Its datasheet is very old and it doesn't explain function of the IC well. It just gives several example circuits and a formula for the output voltage. I want to learn working…
hkBattousai
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Working of Voltage-to-Frequency Converter

I have seen this circuit in a thesis "Voltage to Frequency Converter: Modeling and Design" submitted by Jyoti Ranjan Behra and Rajesh Kumar Barik (thesis abstract, thesis document). In the thesis, they are not explaining the working of this circuit…
Kiran
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Differential voltage to frequency

Edited to clarify some questions I’m working on a design that will take a 0.5V-4V signal from a laser displacement sensor (Keyence Il-1000) and convert it to a frequency signal (0.1-2Mhz) for input to an FPGA counter. The sensor needs 10-30v so I am…
thadwald
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Frequency-to-Voltage Converter: Unexpected Stability Regions

I am using an AD652 as a synchronous frequency-to-voltage converter in the layout shown below. I conducted a series of measurements of the output voltage (Vout) across a wide range of input frequencies (each of which was held constant for the…
Dani
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why three phase induction motor draws current with spike at low frequency by using VFD?

I have built Variable frequency drive (VFD) for a three-phase induction motor using V/F constant control. while I was testing 15HP three-phase induction motor without load with my VFD, the motor draws current with a spike at low frequency. Low…
James Hock
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Problem connecting INA114 with LM331 for voltage to frequency conversion

i'm actually using a load cell and i would like to send the load cell information to an android tablet through jack audio. Then load cell caracteristics are presented here: http://www.phidgets.com/products.php?product_id=3134 I'm using first an…
Nad92
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Low power Analog signal Isolation

In my project, the current budget is very tight. With less than 1mA, I have to isolate sensor's signal voltage and be able to measure it with ADC on the other side of the isolation barrier. What I have thought of is that using VF conversion and…
Steve
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LM2917 Vout decrease with fixed frequency input along time

The problem: LM2917 Vout decrease with the same input frequency along time. The LM2917 input is the Hall sensor (APS11450) output. The sensor reads 8 magnet per revolution. Fixed frequency about 30 Hz. 470 ohm in Vcc line to Vcc LM2917 (Zener…
Pablo
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Threshold ramp frequency voltage converter

My issue is understanding how the socalled "threshold ramp frequency voltage converter" (translation from Italian) works. In what follows the block diagram and in the next picture a time plot of \$V_s\$, \$V_C\$ and \$V_O\$ respectively As far as…
Stefano Fedele
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Require help designing VFC (voltage to frequency converter) circuit

I need to use a VFC (voltage to frequency converter) circuit that operates with bipolar voltage (-10 V to +10 V) and with a bias (i.e. when the input is within +/-2.5 mV, the VFC shall not produce any output). I was looking into…
gari
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Designing a senvitive frequency to voltage converter

I need to make a battery powered frequency to voltage converter that will monitor very minor frequency changes, around 100Hz with base frequency of 3-5MHz (may vary during operation); something like a very wide band FM demodulator. I found this…
Archimedes
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