Questions tagged [undervoltage]
The undervoltage tag has no usage guidance.
97 questions
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Design for circuit with under-voltaged LEDs
I'm trying to design a simple circuit for to power 3 LEDs in parallel off of a battery pack. The ultimate goal is to have multiple of these circuit with transistors that will be controlled through a ...
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Switching time of under/over voltage relay
I would like to know what the switching time of the C/O contacts for this relay is (Schneider RM22TR33), i cannot find it in any documentation:
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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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Is it possible to design an over/under AC voltage protection circuit using only diodes and SCRs?
Is it possible to design a circuit using only SCRs and diodes (Zener or otherwise) as a main regulating device to protect a load (220 V, 80 W) from over- and undervoltage? Other passive components (...
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Undervolting magnetically held switches
I have acquired a Honeywell ET series switch (best datasheet I could find) whose holding coil is rated to run on 28 VDC. I know it is often deployed in aeronautical environments where voltage can drop ...
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Will Undervoltage Damage A Brushless Fan?
I have an off-grid solar panel set up ready and it works really well. My solar PWM charge controller of the back side aluminum heat sink is too hot to touch when its during sunlight.
I was thinking ...
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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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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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Trying to fix leakage issue in this under-voltage cut-off circuit
I have a device that works with EV battery 48 V (40-65 V) input and now I need to cut off my circuit load below 40 V battery voltage to prevent further battery discharge.
I'm trying to simulate an ...
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Measuring the battery voltage while the circuit is under load for under-voltage protection
I have built a flashlight composed roughly of a raspberry pico which delivers a PWM signal to a powerful array of 4 parallel multiple-LEDs chips powered via a half-bridge driver and two N-channel ...
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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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340
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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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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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Low voltage cut-off with delay
I want to put an accessory on my motorcycle that consumes 40mA even it isn't in use, but I don't want to drain the battery.
I want to put a low voltage cut-off circuit with relay set to 11.6V to ...
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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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400 V, 3-phase electrical motor on 230 V, 3-phase supply WITHOUT rewiring?
I have a what I assume is a very unusual question, and an unusual situation. I do appologize if it has been explored before, but I could not find anything about it when searching. I also appologize ...
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Buck converter voltage drop and brownout
I was trying to build a 24 V to 5 V buck converter to create a shield that would power my Raspberry Pi4 via GPIO pins and also connect it to an accelerometer.
The issue is, after powering it up, it ...
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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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low voltage cutoff for negative voltages
I've been trying to design a simple low voltage cut-off circuit for my dual supply +-9V circuit. The positive side works as intended with the LM431 and a PMOS, but the negative side not so much.
The ...
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Undervoltage protection circuit design review
I want to design an undervoltage protection circuit. The nominal supply voltage is \$48 V\$ and the maximum load current is about \$ 0.5A\$. If the supply drops to about \$39 V\$ or below, a P-FET ...
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Node voltage calculation
I'm designing a protection circuit and I'm assuming the following hypothetical situation represented in the figure below, where I need to determine the value of Vx. Does anyone have any suggestions on ...
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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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328
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Simple undervoltage lockout
I have a generator that outputs upto 20v dc, to power a 12v led light I tried a buck+boost converter (xl6009 based), light requires 1Amp on 12v.
Problem is when engine is not accelerated, generator ...
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What is the maximum DOD for a Li-Ion Battery?
I bought these 4.8 AH, 3.7 V - 4.2 V lithium batteries that came without a datasheet and I didn't manage to find it anywhere on the internet. Can someone figure out its maximum safe discharge voltage ...
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Beginner here... is the anode and cathode of the TLV431 mixed up in the linked circuit?
From an earlier question, I know I need discharge protection on the NiMH batteries in another circuit I'm working on. Researching it led me to this link.
It looks to me like the anode and cathode are ...
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What causes undervoltage cell in a lithium ion battery pack 48v100ah? [closed]
The lithium ion battery is composed of 15 cells. It has a battery management system. When I check the battery using the BMS app there is 1 undervoltage cell but the other 14 cells are normal. What ...
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Turning regulator ON/OFF using EN pin (with Zener)
Is it ok to control the EN pin of a regulator (MIC29302) by just simply using a Zener diode?
(i.e. a reverse biased zener from Vin to EN pin and a pulldown 15k resistor to ground also connected to EN.)...
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Transistor for UnderVoltage Lockout (UVLO)
this is a circuit in LM2596 datasheet which suggests using zener+bjt combo to protect against UnderVoltage in regulator input :
it turns the regulator off using its ON/OFF pin.
I have many D882, ...
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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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Undervoltage lockout
I would like to do a simple undervolatge lockout. I thought a BJT as a switch like this:
In normal conditions I would have 30V (and -30 and the othre rail) and 25 mA to 50 mA. These power rails will ...
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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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1200w dc-dc boost converter low voltage protection not working
I've purchased a 1200w dc-dc converter with the model number SZ-BT07CCCV.
I'm using it to convert 12v from a big battery to 24V.
the converter comes with three potentiometers according to the ...
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How to prevent a Lipo/Li-Ion-Battery from catching fire after a complete self discharge with a following accidentally recharge
From the following Youtube video (at 3:15min) I got that it is dangerous to recharge a Lipo/Li-Ion-Battery after it was completely discharged (0V), because it will catch fire.
https://youtu.be/...
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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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Under voltage lockout circuit design
I need to be able to switch a load circuit off when the output voltage from a buck boost converter is around 3V (or below 4V or 5V).
The converter is powered by a 10W solar panel and the load can draw ...
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Undervoltage Testing of a LDO or Switching DC-DC Converter
I am using a Regulator section in - UJA1076 this IC
Input Voltage = 16V
Output Voltage = 5V
Load Current = 0.1A
My question is, I want to test the undervoltage condition 90% and 70% as mentioned in ...
user220456
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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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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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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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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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Voltage protection with 555 timer not working
Briefing
I am using Multisim to simulate a circuit before building it.
The voltage protection circuit with a regulator works fine and the timer circuit works fine as well separately. When I try ...
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MOSFET Gate-Source voltage in protection circuit
I'm creating board which is supposed to withstand OV/UV and reverse voltage. I've chosen LTC4365CTS8#TRMPBF(datasheet) IC to deal with this problem. In reference schematic for 24V input they are using ...
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What is a better way to prevent over-discharge in this low current circuit?
I made a nightlight and was very happy with the dim yet usable output and runtime (months), but my assumptions about battery safety were wrong. I expected the LDO 3.3 V regulator to stop output when ...
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Will this UVLO work?
I'm referring to one answer here
What if (power supply) was 24V, the VCC is 3v3 delayed by 1 second?
If you apply power then your (power loss detect) will be higher than the Vcc rail for 1 second? ...
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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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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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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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Under-voltage lockout programming on Delta D12F200 DC/DC converter
I recently decided on the Delta D12F200 DC/DC converter for my current project (datasheet: https://www.mouser.com/datasheet/2/632/DS_D12F200-1141659.pdf). My project will be powered by lithium ion ...
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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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