1. A

    [SOLVED] Voltage divider 5V to 3V to replace 2 AAA batteries with DC power supply?

    I have this portable rechargeable battery pack for charging smartphones. It is 5V, 2.4A, and 5000mAh. I would like to use it to power a wireless mouse that normally requires 2 AAA batteries, which is 3V and I'm not sure what is the A and mAh. I made a voltage divider that involves a 220Ω...
  2. P

    AC/DC 24v power supply 5a with 8 barrel connectors?

    Hello, First off, I'm a newbie. Not sure if what I'm looking for is doable, possible... I have 8 battery powered light fixtures. They come with 24v, 5a individual chargers. I would like to make a charger where I can charge all my (8) lights fixtures at once without the need of plugging 8...
  3. ShortCircuitJ5

    Battery, Light sensor and a mini motor?

    First the picture, because a picture is worth a thousand words. Is this possible? If the light is OFF, then the motor stops. Low light brigthness = low motor speed. High light brigthness = high motor speed. Thanks.
  4. Younes Thabet

    what's a good power-management solutions for wearables?

    Hello all, I am intending to make a wearable device that have a GYRO, ACC sensors, monochrome display, BLE connection. the wearable will be powered with a rechargeable 50mAh (both wired and wireless charging). I have checked multiple solutions from different semiconductor manufacturers but i...
  5. Bhanu2626

    Does the MOSFET in the Schematic will work fine?

    I using the MOSFET IRFB3004PBF switching. 56.2V is a source voltage coming from the charger and 48 is the nominal voltage of the batter. switch S1 is for switching Vgs. Vgs=5 v. Rgs=10k ohms (connected to the gate terminal and battery ground). battery is 13s3p Nominal=48v Peak=54.6v Will MOSFET...
  6. T

    Battery Life Duration for Specified Voltage Drop

    I have a 8 AA batteries (12V total) that is powering a light that draws .0517A. The light no longer outputs enough light when the battery voltage drops to 8Vdc. Typically I'd calculate battery life via: 2.5Ah * 8 = 20AH. Then: 20AH/.0517A = 386 hours. Does this equation change if I want to...
  7. D

    New to wiring LEDS - what am I doing wrong?

    I like to make things and I had an ambitious idea to make a small scale Griswold house and needed to wire together 100 1.5V 100mA (AC and DC compatible) pre-wired bulbs that are typically used for hobby train use. I am a complete newbie to anything that has to do with lights and wiring, but my...
  8. M

    Help to understand the operating logic of the Bosch charger

    hi, I ask for your help to: determine, if possible, the type of transistor T5, T7 (SMD code: MK3C). help me to understand the operating role of the set T5, T7 and R23, R33 in the circuit (it's like a logical port type AND, but I do not understand how it works). help me understand why the...
  9. bmbouter

    IP5306 Charging Circuit works for 33 seconds then strangely stops

    I'm new to circuit design. I'm using an Injoinic IP5306 battery charging IC (datasheet). I also use an AMS1117-3.3 (datasheet) to drop down the 5V power it produces to 3.3V. I've attached a picture of my schematic which shows the relevant portions, the IP5306 in single-LED configuration, the...
  10. electromeow

    Relay or MOSFET for high current?

    Hi, I have to switch a high current(DC 12V@~60A approx.) for a battery-supplied circuit. But its on-status resistance should be as low as possible. Because you know the Ohm's Law, the I is going to increase up to even 100 amps sometimes, so a very small resistance creates a big difference. I...
  11. oferorgal

    Battery simulator

    Hello, I want to design a battery simulator circuit to test my board. My board connects to a single cell li-on battery, 3.8V 2400mAH and it has a wireless charger circuit with up to 400mAH charge. The battery simulator needs to provide up to 1A to the board and to be "charged" at 400mA. I've...
  12. R

    4s3p battery pack on 2 level

    hi for a diving light, i need to create a 4s3p battery pack (lithium). I can have max 2 level of battery in a delrin cylindrical. What could be the easier wiring for welding? I put all battery on the same side... but it's not mandatory... thanks
  13. R

    DC to 3-phase VFD for providing induction motor with battery power (~8kW)

    I'm building a mobile robot which is quite heavy and needs some serious HP. For this and other reasons I want to mount 4 induction motors to each wheel (for a total output of about 8kW) and power them via batteries. However, those motors need 3-phase current and I obviously can't plug them...
  14. ronit991

    Better approach for powering up sensor nodes ?

    I have a sensor node containing an MCU & radio running at 3.3 V and a sensor running at 5 V. What is the better approach for powering up the system (in terms of efficiency, stability, etc.) : 1. High Voltage Battery + Buck Converter or 2. Low Voltage Batttery +...
  15. J

    Homemade Power Supply How to?

    I'm posting today hoping for some guidance on a project i would like to attempt. I recently came into a lot of 64 12v 7AH Sealed Lead Acid batteries from a backup UPS. The batteries are still good and take a charge and load like normal for the most part. Since i only have the batteries and...
  16. C

    Protective elements for powering dc motors

    Hi everyone! I am building a robot that carries a drill to make holes in the ground. I have not been able to find similar size/power references regarding how to power the motors. I would like to know how to protect the battery and motor drivers, my specific questions are: - Where to place...
  17. E

    how to properly make a charging circuit -- 2s 7.4V to 5V 2A

    I have 2 18650 li-ion cells, each at 3.7v (in case you don't see the pictures, they are available here : https://raspberrypi.stackexchange.com/posts/121847 ) and this bay with this white connector I saw on youtube that depending on the length of the cell, we can know whether they have...
  18. Playdric

    ESP8266 battery power supply

    Hello all, First of all I'm a complete newbie about circuits and electronics. I recently bought a 3D printer and I saw this project on thingiverse. Quick sum up : LEDs (WS2812) lamp controlled by an ESP8266. The main issue is that the firmware of the ESP8266 provided to control the LEDs do...
  19. Prajeet Anand

    Battery impedance measurement

    For the past few days I have been trying to buy a proper battery impedance measurement device that is good and also falls under my budget of 1000 dollars. I will be mostly using it to test 3.7V Lithium ion batteries. Could anyone suggest a good measurement device for that
  20. Dinesh6252

    Can i use a 13s bms for a 7s project? And how?

    I have a 13s bms laying around and I want to use it as a 7s bms, is there a way to do that?any suggestions would be greatly helpful.
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