All Questions
43
questions
0
votes
2
answers
39
views
Boost converter two different voltages (9v/12v) from 3.7v battery, attach both to battery, or daisy chain off 9v
I'm sure this has been answered plenty before but I cant seem to get the search terms. I'm wanting to use a 3.7v battery to power a small 9v device and a 12v device at the same time using a boost ...
- 172
2
votes
2
answers
6k
views
Powering 24 V and 12 V device simultaneously from two 12 V batteries
I have two devices which need to be battery-powered (remote area, no grid power available). One device requires 24 V, the other requires 12 V. Both are very low amperage (~50 mA).
Can I use my two 12 ...
- 1
0
votes
1
answer
95
views
What is the "best" way to make a diy 7v rechargeable battery?
I have a device (the wii "sensor" bar, basically an IR LED array) that the literature says takes 7v. I can't find any battery offerings that come in 7v, but many that are 3.7v, so I am stuck ...
- 1,965
0
votes
1
answer
47
views
Battery consideration and topology choice
I have a system with a battery. I do not know what will be the battery at the moment. And so I can select the voltage battery in function of my system. I need to regulate a voltage (15 V) thanks to a ...
- 15.7k
0
votes
3
answers
97
views
Does DC-DC 24V-12V waste less power than AC-DC 220V-12V?
I am modifying an existing UPS to allow for a longer backup time. I plan on adding a cooling fan along with an external current controlled power supply to charge the larger batteries. There are some ...
- 72.5k
2
votes
2
answers
701
views
How much charging ripple voltage is allowed while charging a LiFePO4 battery?
We are designing a buck controller to charge a LiFePO4 battery (4 series 9 parallel cells, each of 3.2 V).
Hence, we would like to charge the battery pack with 13.90 V but the buck output has got a ...
- 29
1
vote
3
answers
292
views
Battery emulator based on an array of buck converters for BMS testing
Problem: How to quickly and cheaply test if a given BMS (Brand: Daly / Tiny BMS / etc) or battery-powered system behaves as intended for various cell voltage combinations without waiting for actual ...
1
vote
3
answers
113
views
Unable to start and run 12 V DC pump, only jolts
I have a 12V 19 watt DC water pump (800LPH), A 12 V DC step down converter, and two Dewalt batteries.
One at 18 V 5 Ah, other 18-54 V 9 Ah.
I've connected pump to step down to battery correctly, but ...
- 73.2k
11
votes
4
answers
3k
views
Boost or buck regulator for battery life?
I want to make a wireless sensor node that will run at about 2.5v. I am trying to decide between running 3 alkaline batteries in series with a buck converter or in parallel with a boost converter. I ...
- 24.1k
0
votes
0
answers
58
views
Using 2 LiPo Batteries via 2 Buck Converters for External Notebook Power Supply - will it work?
I have an old ThinkPad X220T notebook of which the internal battery is broken (and removed).
To get my notebook working on the go again I want to build an external portable power supply with 2 LiPo ...
1
vote
2
answers
738
views
12 V, 18 Ah battery for a solar panel
I have a 100 W solar panel. I bought a 12 V, 18 Ah battery with a 30 A PWM solar controller. How can I get this to charge right? The current will be too much for the battery. How can I cut down the ...
- 9,270
0
votes
2
answers
652
views
Why does the voltage of a 18650 battery drop when connected to an LM2596 module?
I am trying to get a 5V output out of a 2S 18650 cells (getting a 7.5V from them.)
I am trying to use a LM2596 module, but as soon as the battery is connected to the LM2596, the input reading goes ...
- 4,386
2
votes
1
answer
610
views
Why is LM2596 buck converter output current low when used as a mobile charger? [closed]
I have a LM2596 buck converter which is capable of providing 3 A and my input source, which is a transformer, is capable of providing 5 A.
When I use the buck converter to charge my Android phone ...
- 9,270
2
votes
3
answers
3k
views
Why is my buck converter emitting smoke and fire?
I am powering my router from a 24 V battery, but the power requirement of router is 12 V/1 A, so I am using an LM2596 buck converter.
The specification for this buck converter is as follows:
Input ...
- 9,270
1
vote
2
answers
875
views
Using LM2596 step-down with Li-po
I'm doing a project with an ESP32 (3.3 V), a DHT11(3-5 V), a soil sensor (3.3-5 V, the cheapest Chinese), NRF24L01 (2.6-3.6 V).
I'm using LiFePO4 right now (3.32 V), but when the battery voltage drops ...
- 9,270