A voltage divider is a circuit that produces an output voltage that is proportional to the input voltage. One typical configuration consists of a pair of resisors in series from the input voltage to ground, with the output voltage taken from the junction of the resistors. As an example two equal ...
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214 views
Ripple factor detection and measurement
How to measure ripple factor automatically for a pulsating dc output(0-300 v)?
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269 views
Converting Headphone-Out to Mic-In Using a Potential Divider
I need to record audio with a device that only has a mic-in which is heavily amplified. I built a potential divider with R1 = 10 kOhm and R2 = 4.7 kOhm to get a factor of about 30%. I chose the ...
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Low power design - switch out voltage divider using transistor?
I have a very simple voltage divider circuit for measuring the resistance of a platinum 100 Ohm resistor.
I want to be able to switch out the voltage divider circuit from the power supply in order to ...
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2answers
177 views
Camera circuit with different voltage requirements on arduino
First off - i'm an EE noob, but i've muddled my way through a number of arduino projects, so have some experience there.
I'm building a breakout board for a CMOS camera sensor for use with an arduino ...
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4answers
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Lowering 3.3V to 3V
I am attempting to lower a 3.3V source to 3V for use with a sensor (which has a rating of 3V +/- 0.1V). Based on the other answers in here, I believe that placing two resistors in series would achieve ...
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2k views
What are the advantages and disadvantages of using signal diodes instead of resistors?
In the past to create voltage dividers or protect against back emf I have used resistors, but reading about signal diodes those situations are given as examples. I can't really comment on the inductor ...
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3answers
239 views
Current Drain on ADC
I am looking at a MCP3008 datasheet and it says that it has a maximum current drain of 150uA, and a typical current drain of 100uA.
I am building a voltage divider to knock down 96V to 3V. As this ...
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81 views
Generating three voltages with a MCU
I'm going to try and generate black and white NTSC video, using a micro-controller. According to this:
https://instruct1.cit.cornell.edu/courses/ee476/video/
It is possible to do it using two pins ...
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255 views
how to find minimum acceptable current through voltage divider driving transistor
I'm using a BC557 transistor to control a LED and a uC to control the transistor. The transistor itself is controlled using a voltage divider.
It was suggested to me to use resistors around 100K + ...
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3answers
309 views
Whats up with my photoresistors! (Wonky readings, non-stable, I'm missing something)
I'm working on a photoresistor array with my arduino, and I'm having a little trouble getting stable readings.
I'm driving 7 rows one at a time with arduino's digitalWrite(pin,HIGH) command and ...
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8answers
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How does the electricity “know” the ratio of the resistance in a voltage divider?
I'm having a hard time conceptualizing what/how things are working in a voltage divider setup. I've read a couple other questions/explanations where the answerer has said to "not think about it in ...
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5answers
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What resistor values to use in a voltage divider?
I understand that the output voltage is determined by the ratio between the two resistor values, and that two 1 kΩ resistors will output the same voltage as two 1 MΩ resistors (correct me if ...
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2answers
337 views
ADC reading 96V DC
I have a 96volt DC line, and I am trying to get it down to 3.3volts to put into an opamp, and then to put into an ADC so that I can read the voltage on the line. The 96volt line will be prone to ...
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1answer
204 views
How to divide signal level from function generator
I looked for this answer but was unsuccessful so I want to ask the experts here. I have configured an op amp in non-inverting mode (the first in a chain of 3 stages). It is for amplifying extremely ...
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2answers
1k views
Postive input ==> Positive and Negative output
I was watching some tutorials on thesignalpath.com and came across something that I didn't quite understand (even after it was explained).
toddrharrison
August 21, 2011 at 6:29 PM
Answer ...
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4answers
623 views
Set up an array of pressure sensors
I am working with a flexiforce pressure sensor 25 lb.
I have to run 6 of them in parallel and I'm using an Arduino Uno. I'm not an electrical engineer (read: I'm a computer science major) and this is ...
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2answers
441 views
Confusion with voltage drop equation
I had never really thought of resistors causing a voltage drop, I have only used them to limit current to say an LED.
Using something such as E = IR I can use a ...
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4answers
887 views
Voltage Divider vs. Resistor in Series
What is the difference between having a voltage divider vs just using a resistor in series.
So for example, I have an input voltage with 12V, and two resistors in a voltage divider, R1=10k, and ...
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2answers
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Is this 7805-based design correct?
I found this design on internet:
It is said to be a regulated power supply with variable DC output 5-15 V, 400 mA. My first question: Is this design around 7805 correct? I am asking because it ...
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5answers
558 views
If I'm going to use a potentiometer as an adjustable voltage divider, does the tolerance or resistance matter?
Here's what I working with. I'm researching some three terminal potentiometers for use as adjustable voltage dividers. The outer terminals are connected to 0V and 5V respectably, so as I turn the ...
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2answers
3k views
What is the voltage divider rule?
Can anyone explain what the voltage divider rule is? How has the author of this book used it for analyzing the Voltage Divider Bias circuit for transistors?
And can anyone explain how the two ...
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3answers
671 views
LPC2148 ADC problem with voltage divider for battery
edit: solution found with our new board revision; outside of careless mistakes, buffering the signal with an op amp seems to have resolved the issue (as suggested by Joshua below).
I am working with ...
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How does the input circuit on this oscilloscope manage to accept such a large range of voltages?
I recently bought this ($45!) oscilloscope: http://www.gabotronics.com/development-boards/xmega-xprotolab.htm. Looking at its schematic, I see the circuitry for one of the two analog input channels:
...
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2answers
1k views
Combined ADC scaling and offset with variable input voltage ranges
I am trying to create a circuit which will allow me to scale and offset a voltage (be it AC or DC) to within the range of the Arduino ADC.
The voltage could be anything between + and - 250V, but I ...
