Questions tagged [supercapacitor]
Very high energy-density capacitors, typically measured in farads.
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Trying to design a circuit to power an MCU that demands high current pulses
I'm trying to model an MCU powered on batteries. The MCU will be sending data over BLE, so it will pull a large amount of current; more than the maximum discharge current of the battery. To solve this ...
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Supercapacitor Balancer Circuit
I’m working on a balancer circuit that’s part of a supercapacitor charging system, but I’m having trouble understanding how it works. Specifically, I’m confused by how the values of V1-VA and VE-SCAP ...
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Understanding Negative Active Resistance in Supercapacitors
I'm seeking clarification on a phenomenon I've encountered regarding supercapacitors. Specifically, I would like to understand what is meant by the negative active resistance of a supercapacitor. How ...
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Why are big supercapacitors only available in 2.5-3 V, and not for example in 12 V or 24 V for easy installation parallel to batteries?
I have read that it is possible to directly connect a supercapacitor and battery in parallel due to lower inner resistance of the capacitor. This makes me wonder why are there little supercapacitors (...
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Cyclic Voltammetry for a Capacitor - Positive Current, Potential is decreasing?
In the boxed red region, why is the potential decreasing when the current is still positive? To my understanding, when the current is still positive (i.e. not changing direction), the capacitor will ...
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Supercapacitor discharging fast when there is no discharge path present
This question is a continuation of my previous question, but different from that.
I am using a PCA85073A RTC in my design. On some boards, the supercapacitor discharges very fast (5 V to 1.1 V in half ...
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What will happen if I2C pull up voltage became zero
This is a continuation of this question.
In my board RTC I2C lines are pulled up to controller supply voltage and the controller supply voltage will be off when the system is off.
At that time also ...
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Super capacitors derating
I want to use supercaps in a system for minimal power interruption backup (1-2 seconds). My systems works at - 40 to 85°C.
I have seen that supercaps are usually rated for 1000 - 2000 hours at max ...
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Why is my super-capacitor self-discharging so fast?
I'm experimenting with a night light powered by a mini solar panel charging a super-capacitor instead of battery. (I know, I know. It's not recommended for this usage but I want to try it anyway). It ...
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RTC super capacitor is discharging very fast
I am using a PCA85073A RTC in my design. On some boards, the supercapacitor discharges very fast (5V to 1.1V in half an hour.)
This happens when we turn off 5V_uC.
The circuit is given below.
All the ...
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Wide input voltage capacitor charging control
I'm working on a project in which we are using a bank of inexpensive 100 μF caps (up to 20 of them) to keep a microcontroller powered up long enough to do housekeeping for shutdown when the main power ...
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Supercapacitor minimum voltage
I want to use a supercapacitor ( Lithium Ion 3.8V 30F) to be charged only by a small solar panel. And the circuit will only do something between between 2.7 and 3.3 V. In standby mode the circuit will ...
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Wire size for 16 V, 83 F capacitor [closed]
I have a capacitor bank circuit (16 V, 83 F). I got it from AliExpress. I am planning to install it in my car parallel to my car battery (car battery capacity: 12 V, 50 Ah). Could you please suggest ...
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Test circuit for a solar panel used to power a supercapacitor
I was hoping to power a device with a supercapacitor that would provide power when there isn't light available, so essentially I just need the solar cell to charge the supercap as fast as it would ...
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Super capacitors and getting same current burst out every time using boost converter?
I need to use a supercapacitor to power a circuit for short pulses evenly. So with the same current out every pulse. To do this, I thought to use a boost converter to get a constant current out every ...
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Replacing Li-ion battery in a game controller with a supercapacitor
My game controller's Li-ion pouch battery is swollen and has died. I was thinking if it was possible to replace the internal battery with capacitor/supercapacitor. I don't need the wireless ...
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How to replace a lithium-ion battery with a super-capacitor in electronic device?
I have a mobile WiFi router, which contains 3.7 V pouch lithium-ion battery. But I use it only in one fixed location where the charger always plug in. The problem is, the Li-ion pouch cell will puff ...
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Low power circuit design for powering an e-paper display
This is a follow up to my last question on Low power circuit design for turning an LDO on/off at specific voltage levels, where I wanted to find a low power way to turn an LDO on/off at specific ...
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Low power circuit design for turning an LDO on/off at specific voltage levels
I am designing a low power circuit that uses the TPS61023DRLR for energy harvesting, charging a 1.5F ...
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Design for passive power backup for ESP32 for a few milliseconds
I am designing a logger system with an ESP32 in which the logs are uploaded to the IoT cloud and parallelly logged to a local SD card. On Power loss detection, I want the ESP32 dump all the data that ...
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Use supercapacitor to power microcontroller
simulate this circuit – Schematic created using CircuitLab
I try to solar charge a supercapacitor C1. When it's fully charged, I use a Zener diode D2 to the gate of an logic MOSFET M1, which ...
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Designing boost converter for a supercapacitor source and LED load
I have a 2.7 V 100 F supercap, that would equal 364.50 J of energy based on E = 1/2CV^2. If my load is a series of 4 LEDs with a stack forward voltage of 12 V and forward current of 3 A that would ...
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SuperCapacitor Charger with BQ25173
I am asking about supercapacitor charger with BQ25173 IC. I examined the datasheet and designed my circuit for about 13 mA, but when I built the circuit, the current that was needed to charge the ...
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Super capacitor causing overcurrent protection
I'm making a power-supply circuit for some MCUs using a battery charging-discharging protect module MH-CD42 (both input and output is 5 V).
The module's datasheet says it has a 0.3 seconds switch time ...
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Leakage current in supercapacitors stack
Given a circuit of four hybrid supercapacitors in series, connected in parallel with another branch of supercaps in series (4s, 2p), where the leakage current is illustrated as a parallel resistance ...
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Using capacitor bank in parallel with lead acid battery
I saw some DIY projects about boosting car lead acid batteries. A supercapacitor bank is connected in parallel with a lead acid battery to stabilize the supply.
However, in the market, I can only find ...
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How can I simulate a super capacitor in LTspice?
I am trying to simulate a super capacitor in LTspice but it is not giving me the correct discharge time as it should be theoretically.
Has anyone also faced this issue? Please let me know how to ...
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Supercapacitor to prevent temporary power supply voids
Hello and sorry for the improper title!
We need to transmit about 50 W (5 V 10 A) through a slip-ring-ish to drive some rotating electronics and LEDs.
We are using a 5 V 25 A LED power supply.
We are ...
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Is there any supercapacitor that is hermetically sealed?
Does high altitude affect supercapacitors?
At high altitudes mostly hermetically sealed capacitors are used, so is there any supercapacitor that is hermetically sealed?
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Super capacitor charging circuit
I am trying to build a circuit to power a system for about 30s-1min after we have a power loss (12V going off), so my microcontroller and radio transmitter can send a message alerting the power loss.
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USB inrush current limiting, charging super capacitor
I am trying to charge a supercap over USB. I understand I need to limit the current (ref: usb.org)
This has been discussed a lot here, for example: here and here, but I believe my requirements are a ...
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Help with power buffer using capacitors
Looking for some help on how I might be able to add a power buffer of around 1 hour to an IC using super-capacitors, and be able to recharge it within 5~15 minutes after a power disconnect.
Looked ...
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How does balancing via resistors work? Why isn't it needed inside of batteries?
I am building a hobby project - a sort of supercapacitor powerbank, where I basically connected twelve 500F 2.7V supercapacitors in series. Despite these capacitors being from same manufacturer and ...
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Can I use a large capacitor to boost the current of a circuit for a short period?
I'm working on an RPi-Pico (Adafruit Feather RP2040) project that runs off of computer USB power (5V/500mA-1A).
I need to simultaneously move 3 motors that run at 6V-8V/250mA, but only for ...
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5 V holdup/ temporary backup circuit
I have a project where I'm using an android tablet to power a serial relay, the relay is 20 m from the tablet so I'm using a USB C > USB A hub and a self powered USB over CAT6 extender. When the ...
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Is LT8705 a suitable and easy hands on DC/DC converter for controlling charging and discharging supercapacitor in HESS?
Currently working on a hybridise my agv which is powered by a 11.1V, 3000mAh LiPo to drives two 12V DC motors. My idea is making a semi-active HESS where only a DC/DC converter is used and connected ...
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Using super capacitor with Li-ion battery to power an automated guided vehicle
I have an automated guided vehicle which is powering by a 11.1V, 25C, 6000mAh Li-ion battery. The reason I am attempting to make a hybrid power source to power the automated guided vehicle is to ...
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Super capacitor, water pump [closed]
I want to design a circuit which can store energy from a little 6 V solar panel into a super capacitor and when it reaches a certain amount of voltage (or gets full) , with a steep start , it ...
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Nominal voltage of supercap
Is it possible to replace a supercap e.g. an FCS0V224ZFTBR24 which is a 3.5 V type by its equivalent with a higher voltage (5.5 V), the FCS0H224ZFTBR24? The datasheet of both types is here.
What will ...
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Super capacitor discharge protection
We are developing an active RF timing tag which uses a 3 V 20 F super capacitor as a power source. We will charge the tag at the time of registering a participant. The charge time should be as short ...
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What can cause a capacitor/supercapacitor to not charge up to source?
I'm doing a project that involves charging an experimental supercapacitor with a 9 volt battery and then turning a red LED on with it.
Now, I've asked around what determines to what voltage a ...
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Capacitor bank for delayed solenoid closure
I have a 24 VDC solenoid valve plumbed in line with a 24 VDC motorized ball valve transporting water. These are redundant because it is critical not to have a valve fail and cause an overfill event.
...
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Any thoughts on a supercapacitor battery project?
Just some insight: I am fifteen and have been researching capacitors for a while now.
I have come up with the idea of building a supercapacitor power supply unit solely to power some small electronics ...
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Automatic buck-boost DC-DC 1-15 V to 5 V, 5 A
I've a big 3000 F 6 x supercapacitors bank to work as an aux USB power hub. It gives power while linearly losing voltage to 5 V, then it stops working, because I'm using a 5-15 V to 5 V DC/DC ...
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Powering ESP32 and two MG90S using supercapacitor
I'm working on a drone-dart project.
Dart is controlled by an ESP32CAM and two MG90S servo motors. It is raised to the sky by a drone and then released. The dart falls while attempting to aim itself ...
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AC to DC 6 V for bicycle and super capacitors for lights
I’m trying to design a circuit to enable my bicycle lights and also have at least 2 minutes of standing lights coming from a bicycle 6 V AC hub.
I thought about building a rectifier bridge with 4 ...
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Help with supercapacitor charging circuit
I need to design a circuit to charge a capacitor from 0 to 2V. The circuit should not be that complicated and no matter the type of capacitor, it should never exceed 2.7 V when charging. The capacitor ...
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NiCd vs supercapacitor in high-current discharge
I'm going to build a drone project (no lead batteries) that will only run for 1-2 minutes, but probably at low temperatures (30C-60C C-rate and sometimes -20°C,) so I will need a nickel-cadmium ...
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How does this supercapacitor over-voltage protection work?
I'm designing a capacitor discharge battery spot welder and came across this video on over-voltage protection for supercapacitors. How does the schematic shown at time 10:15 work? If I need to connect ...
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Is the overvoltage protection used in this circuit a normal way of doing it?
The circuit is from a clip on YouTube. VCC is from a stepper motor generator and varies between ~0-30 volts DC.
From what I understand, and please correct me if I am wrong, when the voltage gets too ...
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