Questions tagged [voltage-divider]
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 resistors in series from the input voltage to ground, with the output voltage taken from the junction of the resistors. As an example: two equal-valued resistors will give an output voltage that is 50% of the input voltage.
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Circuit for Reading Power Supply Voltage with Micro ADC
I am working on a project where I need a microcontroller ADC (3.3V range) to detect the voltage being put out by a 24V variable power supply. This is the circuit I came up with to accomplish this:
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wrong voltage reading with DMM after a voltage divider
SN04N is a proximity sensor. It is powered with 12V from a bench PSU. That 12V also goes through a buck that produces a 5V rail to feed an Arduino Mega and many other modules. Grounds are common. ...
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How to calculate node voltage in this circuit
I came across this circuit snippet as part of a larger schematic. It's intended to adjust the trip point of the comparator as a means of testing the overall circuit. My question is: how does one ...
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Capacitive-divider high-voltage adapter
I am reading a paper about the high voltage adapter. This paper uses the capacitive biasing method to make the transistors not be overstressed. VDVS seems to follow the VE. C1-CN-1 is used to divide ...
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Formula for R1 and R2 of a voltage divider bias
Please I'm asking if the stated procedure for R1 and R2 of a voltage divider is correct i.e if its valid way to come up with their respective values. If so, how do interpret the two statements ...
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Using the EN pin of the TPS259474ARPW efuse
TPS259474ARPW Datasheet
I'm trying to figure out how to use the EN pin of the TPS259474ARPW efuse to accept the full VIN range (2.7V to 23V).
As per datasheet, the EN/UVLO pin :
Chapter 7.5 (...
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Can I do voltage division for parallel resistors only?
I understand that voltage division is possible for resistors that go "one after another". However, I was asked to do this for resistors that are parallel. But I could not find any info on ...
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Problems trying to monitor two 3S Li-ion batteries from an Arduino, while powering that Arduino
So what I'm doing might be actually a little haywire, but here goes:
I'm using an Arduino to power a series of relays that control some 24 volt valves. The power source is two Milwaukee M12 batteries ...
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Voltage divider circuit to solid state relay
I'm pretty new to electronics but have been trying and researching a lot recently. Mostly for creating simple circuits for escape room puzzles.
I've been looking into voltage dividers and yesterday I ...
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Can a voltage divider be used to safely lower pull-up voltage?
I'm working with an LTC2950 pushbutton on/off chip that's meant to toggle the enable pins of voltage regulators based presses from a momentary pushbutton. The LTC's enable pin is open drain and is ...
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Monitoring external battery voltage with ESP32
I'm trying to monitor a battery that is unrelated to my ESP32. The battery powers my gate and the ESP32 is powered by POE. The battery is a 12v battery. I am using a voltage divider and the ADC to ...
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Should I buffer my switch button input?
I have external switch with 24v/open circuit.
I think that I only need voltage divider and drive the FPGA input, but something feels weird for me, maybe I need some capacitor for noise? maybe some ...
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Transistor as Bipolar Switch NPN BJT - Cutoff and Saturation not working
I have a Transistor as a NPN BJT bipolar switch - Cutoff and saturation. With load on the emitter to measure a voltage divider. The voltage that reaches the base is 3.3 V and the collector voltage is ...
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Maintaining Linear Temperature / Voltage-Drop Relationship Across Thermistor While Stepping Down Input Voltage
I have a 6VDC power source that is exciting an NTC Thermistor R1 (resistance of the thermistor decreases as the temperature increases, but the relationship is not linear). There is a precision ...
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Voltage Output Regulation for LTC3310
I am regulating the voltage using the LTC3310 switching regulator. I need to obtain 0.73 V on the output which I chose the right resistors for in theory. However simulation on LTspice is giving other ...
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Reading a resistance to earth sensor with a microcontroller
What are the options for reading a resistance to earth sensor from a microcontroller?
Scenario: I'm building a digital dash for a vintage car, using a Teensy 4 as the microcontroller. The car is a ...
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Pushing a button press from a driver to three different transistors with three state logic
I am working on a project within my company that involves a relay board used to control three different motors when an external 24 V button is pressed. The existing setup works based on this principle....
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PWM IC duty cycle not increasing
I was working on the UCC3895 PWM generator but am having a problem getting a complete duty cycle up to 100. I have used the following diagram for my circuit:
I wanted to use the UCC3895 to get a PWM ...
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Calculate voltage with voltage divider
I’m very confused when I have to find voltage at different resistors terminals. How do I do it? Series-parallel circuit.
For example v01 at R2 terminals and V02 at R4 terminals
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Trouble with voltage divider and Wiegand reader
I'm attempting to use a 12 V Wiegand reader with a 3.3 V microcontroller. To drop the voltage from 12 V to a safer level for my microcontroller, I decided to employ a voltage divider. Specifically, I ...
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Resistor divider for power supply
I have a UM66 melody generator IC which requires a supply voltage in the range of 1.5-4.5 V according to this datasheet. I am using a 9 V battery to power the IC and as far as I have researched, ...
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How to create a voltage divider for different (changing in time) loads?
What I need basically is to create a -12V - 0V - 12V power supply from a 0 - 24V DC supply.
The problem is I can't just make a voltage divider because the loads on each part is changing in time. I ...
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Level shifting to lower voltage: logic-gate vs voltage divider
In my design I need to level shift 5V signals to 1.8V, for now I'm planning to use AND gates with the same 5V signal on both inputs and 1.8V as the power source. I got the idea from this document.
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Power supply voltage divider incorrect output voltage
I am currently working on a high voltage (up to HVP-HVN = 2.5KV) power supply. I am having some huge issues in my actual output voltage vs expected output voltage of a voltage divider in my power ...
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What did I do wrong with the MCP3426 ADC? - non linear output
I'm running the MCP3426 on 3.3V supply on my PCB. I want to measure a battery voltage from around 12.5V down to 8V. Doesn't have to be precise, 0.1V accuracy is sufficient.
I calculated a voltage ...
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Efficiency formula for passive complex circuit
I want to find a formula for the efficiency of this circuit, so \$\eta=P_{out}/P_{in}\$.
simulate this circuit – Schematic created using CircuitLab
I know that the real power is given by \$P=VI\...
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Questions about connecting ADS1115 for voltage measurement
Purpose: to measure the voltage on the DC bus (about 600VDC).
ADS1115 Datasheet
I looked at the use cases and saw two connection options (in the first case, we use two inputs, in the second, only one)....
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How can one calculate the output voltage of the following circuit
I have the following circuit. It has a hall sensor IC-MA3 which is connected to an op-amp. The signal has to be within 2.5V.
The outputs P[0:3] are sine and cosine signals with the middle being at 2....
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How to put the LM5143A-Q1 IC in voltage adjustment mode? (From Datasheet)
I'm trying to make my first voltage regulator circuit using the LM5143A-Q1
Buck IC. The datasheet does include examples and all the values required to get the 3.3/5V fixed output, but it barely has ...
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What is the optimal method for interfacing a 12VDC or 24VDC relay using a 48VDC supply in an automotive application?
I need to interface a 12VDC or 24VDC relay into a 48VDC (nominal voltage) battery pack for switching applications in my automotive design.
Directly driving the relay coil with the 48VDC battery pack ...
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Op-amp subtractor circuit
While using Op-amp as a subtractor circuit the input applied to inverting and noninverting terminals are generally referenced to the DC ground of the circuit as shown in the picture below.
Pic credit:...
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Op-amp subtractor circuit not working
I'm trying to design a PCB to measure single phase 220V(rms), 50Hz voltage using the resistance divider and op-amp subtractor circuit.
The schematic is shown below:
When I measure the signal across ...
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Voltage divider with megaohm resistors for low current consumption
I'm designing a circuit that uses the power MUX TPS2116. The design is normally powered by a 4.2 V battery, but as soon as the battery is removed it should be powered by a secondary power source, a 3 ...
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Drain Terminal of a Multiplexer
I am confused about some of the aspects of how a multiplexer works. In particular, I am working with an ADG508A multiplexer. Looking at its functional block diagram (Fig 2, top panel, page 1) and the ...
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Voltage Divider as Input to Level Shifter
I need to shift a 3.3V PWM signal to 5V to power a strip of LEDs. We are using a set of JSTs to connect from an Arduino to an LED strip and so only have access to the 5V power. I am having trouble ...
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What would be the voltage reading at point B when the circuit is supplied with two different voltages?
The given circuit has one fixed resistor connected in series with a bulb. When 12V is supplied, there is a reading of 8V at point B.
However, when the same circuit is supplied with another source of ...
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TB9051FTG OCM Output Connection/Motor Encoder Outputs to STM32 Micro GPIO Input
I am working on a board to control a motor using a TB9051FTG motor controller chip. I would like to use a STM32F0304 to perform control of this motor.
https://www.pololu.com/product/4801
I plan to ...
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How to power 5V MCU from 9V power supply [duplicate]
I'd like to drive some components (via transistor where necessary) which require a 9V supply from the output of a MCU which operates at 5V (typical). This works fine by means of a 7805 regulator, but ...
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SAR ADC load on analog input
How do I know how much load a SAR ADC puts on the analog input and is my application condition measurable?
I am designing a PCB and I would like to read the output of an external potentiometer using ...
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Which topology of power regulator gives a stable voltage output, linear or switching?
I am experimenting on the stability parameter of switching vs linear regulators. By stability I mean how much the output voltage ripple is changing.
A lot of online reading has made me understand that ...
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How to connect a 4x4 matrix keypad to one analog pin?
I watched this video on YouTube, the video's creator shows how we can connect a keypad to just one single analog pin of Arduino UNO instead of using (number of columns + number of rows) pins by using ...
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Transmission Line simulation
Hello I am trying to understand the behaviour of a simulation of a simple transmission line.
Here is the Transmission line in question :
The behaviour is quite confusing to me so I would like if ...
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Voltage divider circuit for DC voltage measurement with protection against AC voltage?
Need some help with making a simple voltage divider to sense DC voltage of 0-30 V range with my DAQ which accepts 0-10 V analog input.
I was wondering if the input voltage is by mistake an AC voltage, ...
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Adding voltage from multiple voltage dividers
I have the following schematic set up, where all of the resistances are known (I just didn't add them to the schematic as they should be irrelevant). If I read the voltage across the ground and the ...
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Replacing a linear softpot (ribbon sensor) with a regular potentiometer
I'm a beginner with electronics. I'm trying to replace a softpot on a cheap synthesizer with a regular potentiometer. As far as I can tell this component (pictured below) behaves just like a 10K pot; ...
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Gate-source connected MOSFETs for voltage division
Currently, I am engaged in the design of a Thermal Shutdown circuit for an LDO regulator. In this endeavor, I have obtained a circuit schematic from a senior colleague, which utilizes three NMOS ...
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Voltage divider explanation
I am self studying linear electrical circuits and I have a problem using the voltage divider. To my understanding if I have voltage source and two or more resistors connected in series I can use the ...
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Nodal voltage with a current source
I'm trying to understand the behavior of the circuit below containing both voltage and current sources.
I don't really see how can we get 30 V at the node in the middle when we have only 20 V voltage ...
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Why do we use a voltage divider to measure the voltage of a thermistor? [closed]
Can someone explain to me when and why I should use a voltage divider when I design a circuit?
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Two bandpass filters in series, why use different voltage dividers?
I know my question is a bit broad, but I want to ask: Using the single supply configuration, why does the first stage's non-inverting input and second stage's non-inverting input use different voltage ...
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