Design of lead acid battery charger

[khatus]

Hello guys, I wanted to design a lead-acid battery charger using CN3767 4A, 12V Lead-Acid Battery Charger IC. I wanted to know what features a lead-acid battery charger should have?

I am following this circuit.


Any additional circuitry for improvement??

[floobydust]

Never heard of Consonace semi before. CN3767 does not have temperature compensation for charging voltage. Greenland is arctic weather, no?
So the IC is a fail. Shill would not buy.

[David Hess]

Features I would want in a good lead-acid battery charger:

1. Temperature compensation.
2. Charge to the equalization voltage, about 14.2 volts, and then once the current drops, switch to the float voltage, about 13.8 volts.
3. Remote sense if the charger cannot be located at the battery.
4. Input current limit to protect the power source.

[salihkanber]

Keeping Lİ-Ion chargers, your work will be easier. I suggest a literature research on the topic, there are lots of online papers on many online resources.
For example: https://www.powerstream.com/SLA.htm or https://www.batterystuff.com/kb/articles/battery-articles/battery-basics.html

[floobydust]

What comes first? Selection of the IC to use, or the Project Requirements?
For lead-acid, there are anything from 2-stage to 8-stage chargers out there nowadays.

OP's IC is fixed 14.8V equalization and 13.55V float, SSOP-10 with no thermal pad yet good for "up to 4A"?
The extra reverse polarity protection mosfet does nothing for the buck diode, which will smoke. But USD $0.75 though. It seems to be a small semi company with good intentions but unrefined products.

[NiHaoMike]

OP's IC is fixed 14.8V equalization and 13.55V float, SSOP-10 with no thermal pad yet good for "up to 4A"?

It doesn't handle the current directly so the chip's "4A" limit is most likely limited by how large of a MOSFET it can drive. Add a buffer and there would be no theoretical limit to how high it can go.