1. What voltage and current does the modified charger provide?
The TL494 controls the 12 V rail to reach 4.2 V × cell-count, so 8.4 V–21 V. Current is limited to 1 A by a resistor on the second error amplifier [Elektroda, szon, post #17358035]
Universal Li-ion charger with ATX power supply
TL;DR
- Builds a universal Li-ion charger for packs up to 5S from an ATX or AT power supply.
- Uses automatic fan control, a charged-pack detector, and a balancer to manage charging safely.
- A LED bulb power supply provides 22V and is stepped down to 12V for the fan-control and charging modules.
- The TL494 circuit uses a second error amplifier for charge-current regulation, then switches 4.7k in parallel to cut current to a very small value.
- The project is practically checked and reported as working.
Generated by the language model.
Hello, I wanted to present one more project using an ATX power supply and in my case AT. I made him a battery charger. Li-ion up to and including 5S. I looked at Interk a little and did not find anything similar, so I think it is my project, so to speak. I used it to automatically turn on the fan so that it does not make unnecessary noise, and the module to detect a charged battery pack and of course the balancer http://www.zajic.cz/omezovac/omezovac.htm. To power the fan control module and the charging module I used a LED bulb power supply giving 22V, lowered it to 12V. The rotary switch controls the power supply voltage by selecting the RX resistor and including it in the appropriate balancer sections. I also used a second error amplifier in the TL494 circuit to regulate the charging current, and after charging the charge module connects 4.7k in parallel to R1 4.7 resistors reducing the current to a very small value. The project is practically checked.
Comments
Nice design. How's the current efficiency? [Read more]
Current efficiency is high, it is known that a computer power supply has, as I wrote, I used a second error amplifier to set the current at 1A. the other amplifier in a typical power supply is blocked.... [Read more]
I'm just missing a specific balancing module that you could adjust from scratch. There are a lot of modeling chargers, however, the balancing power does not exceed 0.2a to 1A on targets. A balancer... [Read more]
I don't know what you mean. As I wrote on the second error amplifier, I made adjustments to the charging current, I set the current to 1A, I could have set it to a different value. I could also install... [Read more]
I can already see those 10A flowing through the thin cables and delicate balancing connectors in the modeling package ... [Read more]
And who said they would be thin. It is important to be able to adjust the balancer current. [Read more]
You have no idea. In my case there is no such thing as balancer current regulation. The balancer is used to charge individual cells to the same value, and prevents overcharging a cell, which is dangerous... [Read more]
The charger loads each target separately or the whole package and only balances [Read more]
The charger loads the package and balances. In addition, I write that the charge detection system monitors 2, 3, or 4 cells. I gave up monitoring 5 cells so as not to complicate the system because if you... [Read more]
It's not what I expect b planning a 13-cell charger [Read more]
Could you do the characteristics of the current and charging over time .. How long does the charging itself, as it selects the current. [Read more]
I wrote about it in the project description. I used a second error amplifier in the TL system to set the charging current ... which is blocked in a typical power supply. at I set the current at 1A using... [Read more]