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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Reading Flow Meters from Mic Port

I am attempting to read two hall-effect flow meters through the audio-in (mic) port of an Android device. I want to be able to read both flow meters independently. The audio-in port is a standard ...
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1answer
98 views

Ohmmeter not working as expected

I am trying to build a simple ohmmeter by creating a voltage divider and then using an analog pin on a PIC18F2550 to read the output voltage and determine the ohmic value of one of the resistors. I ...
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1answer
35 views

ADC Differential inputs

I am trying to feed a 5V signal to AD7705 which is a 16 bit ADC and expects differential inputs. Do I need to divide my 5V signal using bridge and then feed it to the ADC or can I use it as a single ...
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3answers
77 views

How to create precision reference 2.5 voltage

Can I create a precision reference voltage of 2.5V using 7805 regulator and ordinary resistors(10% error)/diodes or do I need to rely on specific reference voltage generator?
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3answers
91 views

Voltage shift from 5V to 3.3V

I'd like to use MX-05V 433MHz receiver together with a Raspberry Pi. The MX-05V operates on 5V, but the Raspberry Pi's inputs only allow 3.3V. So i need to shift the RX data output level from 5V to ...
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1answer
23 views

Current Regulation in LED Driver and PFC Circuit

Datasheet: http://diodes.com/datasheets/AL6562.pdf I am trying to understand how this IC works block by block and I am confused about over-voltage protection in the error amplifier - specifically ...
2
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3answers
210 views

Convert an audio signal to 0-5V using single supply op amp

I'm trying to capture an audio signal using an analog input of an Arduino Uno. The Arduino's analog input must be between 0-5V. I'd like to use a single power supply via an 9V battery, so I'm using a ...
0
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1answer
71 views

JFET voltage divider bias calculations

Hi im having some trouble with knowing how to perform calculations for \$I_D\$ in a simple JFET where it is biased by means of a voltage divider. I understand that use of the equation: $$I_D = ...
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3answers
83 views

Control 3.3V IC using Arduino?

I'm working with an IC that can't take more than 3.3V (+/- 0.2V), including on its I/O pins. I want to control it using Arduino, but its PIN's are 5V. Now I'm wondering if I can use PWM to archieve ...
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4answers
92 views

How does the resistance of the load affects a voltage divider?

Every explanation I've seen so far about voltage dividers, only consider the two main resistors (that do the "dividing"), and pretty much ignore what happens after ...
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2answers
85 views

How to regulate a 3.6 V battery to two power rails (3.3 V and 1.8 V)?

I have a 3.6 V battery from which I need two voltage rails, one that is 3.3 V and one that is 1.8 V. How should I design this circuit such that it is the most power efficient? Here is what I was ...
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3answers
514 views

What is the function of voltage divider in the below circuit?

Hello I am a beginner in electronics and eager to expand my knowledge in it. Earlier I was trying to build an Ultrasonic receiver using a transducer and some op amps. I ran searches in the Internet ...
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1answer
172 views

Clock divider circuit with flip D flip flop

I am using D flip flops in my clock divider circuit. I have started with one FF and moving up with the number of divisions I want to have in my clock. This is how I want my D ffs to work. Now I ...
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2answers
51 views

Particular current divider

Consider this circuit: simulate this circuit – Schematic created using CircuitLab (this part is preceeded and followed by other components). $$I_1 + I_2 = \displaystyle ...
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2answers
71 views

Alternative to V divider for high currents

I am looking for suggestions as to how to supply power to a gate drive optocoupler i am using. The supply being used is a 25V (rms) ac supply and intend to supply 10V DC at around 500mA+ from my ...
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5answers
107 views

A simple voltage divider

I attended a workshop on troubleshooting and we were asked to find the flaw in the given circuit. A guy pointed out to the organizer that R3 was short ckt and R2 was open ckt. However I was pretty ...
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3answers
59 views

Choosing the right voltage divider by load

I'm using an Android IOIO board to detect simple digital pulses from a 12v source. The input pins are 5V tolerant. Would a simple voltage divider work in this situation? I guess my concern is whether ...
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1answer
54 views

How can I rearrange the voltage divider formula for R2?

Can I please have a step by step explanation as to how I can rearrange the voltage divider formula to find R2. I dont understand how I end up with R2 = R1 x Vout/Vin - Vout.
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2answers
190 views

Sensing AC high voltage to microcontroller

I'd like to sense if I have AC 220V 50HZ available, and convert it to some logical level. I made such circuit, will it work? I use C1 as a resistor. Any recommendations what can be improved? ...
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2answers
76 views

Converting Voltage [duplicate]

I have a pair of batteries that can operate at 7.2V (series) or 3.6V (parallel) and I need to power up a device using 5V. I can use a Voltage Regulator to down voltage at 5V or I can use maybe ...
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1answer
47 views

Enable pin with maximum 3.0v

I've an Enable pin active-high that have maximum voltage rating of 3.0v, but I use a 3.3v MCU outputs. I've also a 3.0v voltage regulator on board. Should I use resistor voltage divider or there is a ...
0
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2answers
182 views

Voltage regulator from 24v to 3.7v [duplicate]

I need to build a simple voltage regulator that can drop voltage from 24V(from a DC power supply) to 3.7V and supply at least 2A or more(up to 5A if possibile). Can I just use a 2 resistor voltage ...
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2answers
149 views

using the Arduino internal reference 1.1v

So i want to measure a resistor of around 20 ohm in a voltage divider with an Arduino UNO R3. Is there any way on an arduino to use 1.1v instead of 5v? I want to do this to decrease the current, ...
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3answers
169 views

50 ohm terminator — voltage divider?

OK, obviously I'm misunderstanding something. I have a RedPitaya, which is an oscope+generator. Its output impedance is 50 ohms. If I send a signal from its output to its input (which is 1Mohm) ...
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3answers
257 views

Transform a 0-10V into 0-5V and use op-amps as buffers?

I would like to transform a 0-10V into a 0-5V so I can read it with "5V MCU" (like the AVR/Arduinos). In the most basic case I would just put 2 resistors and do a divider, but since I don't know how ...
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1answer
99 views

Capacitors Not Charging Uniformly

I have 2 identical PowerStor Series XB supercaps connected in series. Voltage rating of each is 2.5V. In series their capacitance is cut in half but the voltage drop over both of them should be ...
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1answer
52 views

TDA 2030 emmiting voltage to Line in

i've build 15w amp from TDA 2030 but currently i measure from input line to ground (measure are performed from audio jack), reaching 400 mV, my question is: -is that normal? how i can remove it? even ...
2
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3answers
323 views

Next level of resistor divider

I know how to calculate proportions of resistor values in resistor divider, but dont know how to jump into "next level" and calculate the precise values of resistors from proportion : For example to ...
2
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2answers
231 views

Transfer function of an op amp circuit

Let's suppose the following circuit: I am trying to find a relation between Vs, V1 and V2 at this circuit. Please note that Vs is measured in relation to the ground. I have declared some extra ...
0
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1answer
110 views

How much resistance will I need to drop the voltage?

9 Volts is applied to circuit. There is an LED which runs on 3 Volts. I want to drop 6 Volts. how much resistance (\$R_1\$) would I need for that?
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1answer
90 views

How can I boost/limit a signal to TTL levels?

I am researching a data acquisition system to measure the amplitude and frequency of a 4,100Hz 5v-25v AC square wave signal. Actually this is version 2 for me, in the previous version I analyzed the ...
3
votes
1answer
323 views

Is interfacing the 5V TTL UART with 3.3V microcontroller via voltage divider possible?

I need to connect my MSP430 microcontroller (3.3V) to interact with a 5V TTL UART camera ...
4
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4answers
512 views

Circuit for a coarse and fine setting potentiometer?

I've tried to find a circuit for a coarse and fine adjustment (two potentiometers) voltage divider, but I don't understand it and/or they don't have a linear response. Problem: I want to have an ...
2
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4answers
263 views

Sensing analog voltage on Arduino without loading the input circuit

I want to design a voltage divider for my Arduino Analog input pin, to be able to sense the change in voltage in a 9V, 250mA circuit (without loading it). Ive programmed the Arduino so that as soon ...
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1answer
142 views

Colpitts oscilator - purpose of voltage divider

I'm confused by the Colpitts oscillator shown below: I've marked my understanding of the various components, but I'm having trouble understanding the tank circuit. My understanding is that C1 and ...
1
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1answer
186 views

Scaling 12V PWM signal to 0-10V

I'm trying to translate a 3.3v PWM signal through an optocoupler to the 12V side of a circuit, filter it to obtain a relatively clear DC voltage, and scale that to 0-10V for a control element. So ...
0
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2answers
48 views

Arduino AnalogIn minimum current?

I've got a 12V source which I want to measure the voltage (or basically, just to check it's there) so have a voltage divider. Currently, with a 10k and 3k resistor, that brings it down to 2.77V and ...
0
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2answers
67 views

instrumentation of V-divider dual-thermistor circuit

here's the circuit - voltage divider with 2 matched thermistors ("matched" means close enough that the measured temperatures when thermistors are right next to each other comes close enough for my ...
0
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1answer
60 views

DC voltage stepping down but keeping current uchanged with no regulator [closed]

Is there any way to divide DC voltage or stepping it down but keeping the current peak unchanged? But I can't use a voltage regulator. In fact, I want to make a regulator 5V output into 4.5 ~ 4.7 V ...
2
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3answers
221 views

Questions on Operational Amplifiers

What I've learned so far from Navy school is that operational amplifiers are used as a substitute for transistor amplifiers and they contain three main circuits: the differential amplifier, common ...
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1answer
67 views

How to connect a jack lead to the input of a 741 circuit

Below is a diagram of a 741 circuit with a microphone attached, I've built the circuit and it works reasonably well. However is it possible to connect a jack lead to the circuit instead of a ...
1
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2answers
84 views

What is the best practice to generate positive and negative voltages to power an OpAmp [duplicate]

I would like to supply +4.5V & -4.5V to OpAmp using a 9V battery. I have tried using voltage divider which works. Please suggest if this is the best practice, are there any better ways of doing ...
0
votes
1answer
63 views

Feeding arduino with AC?

Im having trouble trying to understqnd this circuit , as you can see from http://www.instructables.com/id/Arduino-Audio-Input/?ALLSTEPS its a circuit that will amplify a signal from 200mV to 2.5V and ...
2
votes
2answers
204 views

Determine input resistance of a DMM using a voltage follower

In my electronics lab we constructed a voltage divider that consisted of two \$1\$M\$\Omega\$ resistors and measured the voltage drop between the two resistors and ground. We supplied \$15\$V and ...
0
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1answer
136 views

Current Sensing with ACS712 on Beaglebone Black

I am planning to use my BBB to perform some current sensing and was wanting to use the ACS712 chip. The chip operates off of 5V, but the analog inputs of the BBB have a max of 1.8V. How can I wire ...
0
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1answer
109 views

Can a simple voltage divider circuit be used to accurately measure voltage?

I have a discharger circuit that I intend to hook up to a 3V battery. Total resistance of the circuit (depending on how fast I intend to discharge it) will vary from 0.04 to 0.01 Ohms (that's 75A and ...
0
votes
2answers
105 views

Regarding the design of a basic voltage divider

I've just entered the fabulous world of circuitry and was wondering about the design of voltage dividers. I understand their function and formula quit well, but was wondering about the actual ...
0
votes
1answer
61 views

Downshifting binary signal from higher to lower voltage using an LM339 comparator

I'm working on an experiment where I'd like to shift a 24V on/off signal down to 3.5V or 5V (i.e. suitable to use with an Arduino or Raspberry Pi). For simplicity and safety - I really don't want to ...
0
votes
1answer
107 views

XBee (S2) Voltage Divider to Read Input 12v Alarm Output Pins

I have an XBee Series 2 and I was trying to detect an input from a signal which was 12v, so I used a voltage divider with R1=220k and R2=24k, I checked the output voltage with multipmeter and it was ...
0
votes
5answers
80 views

For a voltage divider circuit, why does \$V_{out} = I \times Z_{2}\$?

For a voltage divider circuit, why does Vout = I*Z2 ? I understand that Ohm's Law says V = I * R, but I am new to electronics. Can you explain this better? Why is Vout not I*Z1?