Questions tagged [undervoltage]
The undervoltage tag has no usage guidance.
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How bad is it to undervoltage a 12-volt lead-acid battery?
I had a heated discussion with a few colleagues today revolving around how low of a voltage was alright for 12 volt lead-acid battery; they were in the opinion that the low voltage warning buzzer and ...
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Is there any benefit to using a voltage booster (such as Batteriser) on "dead" batteries?
The Batteriser [Edit: removed dead, harmful link] is a crowd-funded product intended to extend battery life by boosting the voltage. It is basically a joule thief that is in a tiny package that slips ...
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Circuit to protect against undervoltage?
What is the simplest way to regulate the min DC voltage in a circuit?
Is it possible to do with zener diodes?
...
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5
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What is purpose of an Undervoltage Sensing Circuit?
I am wondering what is the purpose of an IC such as the MC34064. Is it just to ensure a reset of microcontrollers upon power up or are there other reasons? I used to make a simple transistor switching ...
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To protect a LiPO cell from undervoltage, how low current is low enough?
This may seem like a topic beaten to death, but bear with me.. this is an apparently ignored wrinkle. Over the past several weeks I've been designing various circuits to protect a LiPO cell from under-...
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how to build a low-voltage disconnect switch for DC 12.4V 70A?
How can I make a device that will make the power connected as long as the voltage of the power-supply keeps over 12.4 V (adjustable) and disconnect it if it falls below?
It also must connect the ...
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Under Voltage Protection for LiPo Battery
I have a 3Cell LiPo battery which I am going to use with an RC Car, and I want to design a circuit to protect the battery cells from going under ~3.3v each. So what do you think of this design?
As ...
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Placement of undervoltage monitor and cutoff
Suppose I have a circuit running at 3.30V, supplied via an LDO regulator (e.g., ADP124), powered by a Li-ion battery. In other words:
Now, I would like to implement an undervoltage cutoff to "turn ...
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2
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Scaling voltage to meet two conditions at once
I am using an IC (STM6600) which, among other functions that I need, is also capable of Undervoltage Monitoring. It works like this:
The IC monitors VCC in comparison to two thresholds, V_Low and ...
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Stabilizing the UVLO feature on a DC/DC converter
Very many DC/DC controller IC's utilize an under voltage lockout feature by way of an external pin monitoring the applied voltage and comparing it with some internal reference, putting the IC into ...
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Lead-Acid battery discharged to 5V - how much damage?
Something in my bike (USB Charger, Hella Socket itself) has made a short circuit leading to deep discharge of Lead-Acid battery.
Battery was down to 5.2V for time counted in minutes.
I've ...
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3
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UVLO for Energy Harvester circuit
A good background on the problem can be found in the document: (Under Voltage Lock-Out Design Rules for Proper Start-Up of Energy Autonomous Systems Powered by Supercapacitors).
The above document ...
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Decoupling capacitor across Raspberry Pi GPIO input (+ Arduino + robotics)
I've been messing around with a robot kit from Parallax (the BOE Shield Kit), which has a 5xAA (7.2 V?) power source. The BOE shield includes its own 5 V regulator, which is used to control servos ...
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Can the UVLO threshold be below the minimum supply voltage?
I need to reduce the power dissipation of a MOS used in a battery charger MCP73842.
To achieve this, I can reduce the supply voltage. From the datasheet, I see that the minimum power supply voltage is ...
user220456
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4
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Possible to fry a circuit with a power supply under its current requirement?
I recently had someone explain to me that he was told he fried a laptop's hard disk by putting it in an external drive enclosure that was not rated to supply sufficient current. (Apparently the disk ...
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How do ASIC designers approach designing for extremely low supply voltages like 0.3V?
In ASIC design, there is a tradeoff between performance and energy efficiency. Since most consumer CPU's are designed for maximum performance, they operate at high voltages and clock frequencies, ...
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Do LEDs Need UVLOs (Undervoltage-Lockouts)?
I'm currently working on a project involving (I think 3mm, 1.5VDC) Infrared LEDs. However, due to my photoresistor, I think the current, voltage, or whatever (forgot) will vary greatly to minuscule ...
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11-16V DC voltage stabilization for 13.8V powered ham radio
I am looking for any resources on how to construct a relatively high power (25A, 13.8V) voltage stabilizer (or voltage booster if you like) for my 13.8V powered ham radio.
The problem I try to ...
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4
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Undervolting PWM fan from 12V to 5V [closed]
What will happen if I feed a 12 Volts rated PWM fan with 5 V driving voltage?
Given all the other variables stay the same (PWM control signals) - will it reduce RPM? By how much?
What happens to the ...
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1
answer
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Voltage Cutoff Circuit for battery based application
Here is schematic of battery charging circuit. The battery voltage at 100% charge is 4.2V and it gradually decrease and is 3.2V, discharging below 3.2V will affect the battery life.
How to make sure, ...
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2
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ST1S10 step-down regulator - can I drive the EN pin from the voltage divider?
The ST1S10 step-down regulator has an INHibit (active low) / ENable (high) input terminal, like many other DC-DC regulators.
I'd like to use it for an UVLO function. I initially thought of matching a ...
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1
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Safe operating area for different types of battery chemistry?
I'm trying to find the safe operating area for various types of batteries; in particular I need minimum and maximum termination voltages, although information on temperature / power / current is also ...
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1
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Pump undervoltage protection
I'm planning on building a solar powered pond filter for my koi pond and my setup goes like solar panel to charge controller to inverter module to pump. I have tested the setup and it works when the ...
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2
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Combine voltage sources [closed]
I have a Baldor DG6E generator. It must produce 120V/240V but I bought it and it has three wires as outlets - every one produces 120V. I want to combine two wires to produce 240V. How can I combine ...
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1
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USB current limiter and under/overvoltage protection
I know recent motherboards already provide these, but lately USB ports are also available in many different gizmos (smartphone chargers, TVs, standalone players, etc.), which I am often tempted to use ...
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1
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Short-circuit protection, reverse polarity automotive
I am designing a power circuit and would like to integrate the ic VN5160S to protect it, but I have doubts about the position of it.
Would the ic VN5160S be before the DC / DC converter in my circuit?
...
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0
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Simple Zener diode circuit for UVLO
Please see this circuit attached in this post/.
Basically, I want to build a simple UVLO CCT for my LED controller and I came up with this circuit.
simulate this circuit – Schematic created ...
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Under-voltage lockout and a 555 (astable 50% duty cycle) lets LED flash – now save more power
The following project is built:
A 9 V battery is used – no socket required. This is important to gain experience for future projects.
There is an under-voltage lockout, which switches off when the ...
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2
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How to supply either 5V or 0V without the gradual PSU voltage bleed?
I have a 200W 5VDC power supply (Meanwell LRS 200-5). When I shut off the AC it takes about 60s for the supply to drain fully through the connected sensitive components (processors and storage drives)....
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Are there any single chip solutions for single cell LiPo battery protection? If not, any references?
I can't seem to find one, but does anyone know of a single chip solution for LiPo battery protection on a single cell/3.7V battery? Looking for things like over-current/overvoltage/undervoltage ...
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Choosing values of resistive divider, versus pullup resistor value
I have a slight Catch-22 with my circuit portion shown below.
The ADM6320 is, among other things, an undervoltage detector with factory threshold of 2.93 V (thus Reset output pin toggles when VCC <...
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Should I add an undervoltage protection for lithium battery-powered projects?
I am designing a board with a microcontroller (an ESP32) that will be in deep sleep most of the time. The board will run on a 1-cell lithium battery (not sure if I will use a Li-poly or a Li-ion).
...
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2
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Can Li-ion BMSs be used with Li-po batteries?
I'm building a robot that's running on a 12S, 10400 mAh Li-po. Because of obvious reasons, the system requires a protection circuit.
Can I purchase this 13S (which I suppose works with lower S values ...
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338
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Implementing UVLO on battery charging and boost controller ICs
I recently bought a Adafruit PowerBoost 1000 Charger and found out it does not have 32.V UVLO to protect the battery.
The boost controller IC has low voltage sense (LBO goes low when undervoltage) ...
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1
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Constant current driver and undervoltage protection for lipos
I'm searching for a way to drive a couple LEDs with a single-cell LiPo battery, such that the LEDs will be cut off completely when the LiPo voltage drops below, say, 3.3V.
PCB space, component count ...
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Undervolting BLDC motor on electric bicycle
I plan to build a DIY electric bicycle using a standard geared BLDC hub motor (36V and 250W rated, 500W peak). To get 36V rated battery, at least 10 Li-ION 18650 cells are to be connected in series (...
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1
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Reducing the start-up voltage of a low voltage cut-off circuit
I just built this circuit, with the intent to use it as a low-voltage cut-off switch for a single li-ion cell. It works great, but once it's triggered it needs about 7 volts to turn back on, so I ...
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1
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Low voltage cutoff circuit with Zener and BJT
I have a circuit that's supposed to cut off at <4V. It instead caps the voltage at 3.3-ish and reduces the voltage linearly below that.
Zener - 3.3v
Source - 5V +-5V
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Help with high current single cell lithium charging
I am designing a system to charge a single cell lithium battery. It requires pass-through, path-selection, over and under voltage protection. The bottom line is this system needs to power a device ...
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0
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Using TL431/ATL431 to make UV lockout circuit for gate driver IC
I am using UCC5350 (isolated gate driver) in 3 phase bridge circuit, sadly I decided later in the project to use isolated Bipolar dc/dc converter MGJ2D241509SC (+15/-9) for gate drive supply. 15 V ...
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Voltage stabilizer or voltage protection device for irrigation setup [closed]
I have an irrigation setup in a rural area with voltage fluctuations.
The irrigation setup consists of a Hunter X2 Controller powering a pump start relay which in turn runs a 1.5 HP submersible motor ...
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0
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Modifying XL4015 CC/CV Buck Converter for Undervoltage Lockout
I am trying to convert a XL4015-based CC/CV buck converter module to CV with undervoltage lockout. At this point I am hoping someone can double check my schematic for glaring errors before I attempt ...
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0
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Connecting a second power source to a drain of an OFF P-Mosfet
As a follow-up question to my previous question regarding a circuit that passes voltages above 17 V, I wanted to be sure how to connect output of the solution circuit to my application.
The output is +...
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Arduino USB Protection
I am an absolute novice when it comes to electronics. I want to use a PC to control an Arduino UNO clone that will in turn control a
strip of 122 neopixels. My fear is that I will somehow damage the ...
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0
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Choosing the right Over-Voltage protection circuit
TLDR :
Ideal supply voltage of a device is 12v DC (labeled near jack).
User may mistakenly provide anything from 3 to 24 DC (or maybe 220v AC).
how to protect the circuit against Over-Voltage ?
how to ...
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resistor selection for TPS3700DDCR undervoltage circuit
I am designing an undervoltage circuit for a lipo battery project. I found this tutorial here which lead me to the TPS3700. I am wanting the undervoltage condition to be 3 volts. The part that I am ...
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How can I use 2 Tp4056 as protection circuit for diy 2s li ion battery?
Hi I want to use 2 Tp4056 modules as over-discharge protection circuit for my DIY 2s li ion battery pack.
Those will not be used for charging! hence will not share input! The load is an arduino nano ...
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3
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A device used to logically turn on a circuit with voltage being the input parameter
I’m working on a project which utilizes a power-source which is liable to vary. I have a micro-controller sitting at the output of an LDO (Low Dropout Regulator).
I’m concerned about the LDO ...
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Smart undervoltage protection
what is the simplest way to regulate the min DC voltage in a circuit?
...
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0
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Undervoltage/capacitor problems with Raspberry Pi
My question is about the correct way to add a capacitor to a circuit with a Raspberry Pi driving a servo.
I have seen undervoltage events in the logs of my app when the servo runs so I added a 470uF/...
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