DS2711 IC for charger... i need some help with 2 pins ...

[bbogdan]

ds2711

The idea is that i don't know what to do with the ICHG & IFB pins. Where do i connect them ?

I want to make the PARALLEL CONFIGURATION WITH EXTERNAL CURRENT REGULATION .... and i'm using the schematic found in the data sheet >> **broken link removed**

and here >> **broken link removed**

At my designed circuit so far... i've added some voltage regulator +5 V ... like in this image >> http://img64.imageshack.us/my.php?image=clipboard021pj.png *the part in the left is the voltage regulator


So...do u have any idea how to make this charger....a functional one ? I've read the data sheet...but didn't discover anything

 

[Microemission]

ds2712

Hi, I've tried to build this same charger, with parallel configuration too with some results.
That schematic you posted does not have that CSout pin connected that is a pin that is used to control the amount of current from the power source.
So I gave up on DS2711 and instead of that one I've built the circuit based on Figure 5 but that is for DS2712 only I ordered also a DS2712 sample so thats why I was able to do that.
But now I think that even if that CSOUT pin is left floating the circuit will also work, as it only an output and the IC does not care if it's connected or not and thus not influencing the internal state machine.
Also, on the circuit with DS2712 I've been able to charge only 2 kinds of rechargable batteries, Sanyo with NIMH with 2100mAh and Panasonic NIMH with 2100mAh.
Tried with less known brands like one Noru with 2400mAh and GP with 2100mAh and fault would occur after a bit
That could be because I've built the current sensing resistor RSNS by paralling serveral low resistance resistors, and the accuracy of the charging can be diminished this way I think.
Also the FCX718 I exchanged with a equivalent 2SB985 and don't know till which extent they are compatible on the circuit in hand.

Also the source I'm using is from a computer power supply, to give more current to the batteries, in theory, as I dont know how much current is drained from the source.
Hope it helps

 

[bbogdan]

ds2712 circuit

Ah....

Some time ago ... like one year (2005... beginning of 06) i was also trying to build a charger : a smart one. Browsing the net i've find out about MAX712/713 ( this one i can recommend it)>> **broken link removed**

But...i was not so experienced and i didn't have faith that a company can give FREE samples ... free of charge... not any the transport must be paid. So... i didn't ordered. Now... as a joke really and by curiosity i've ordered not 2...as it was default...but 1 IC ... DS2711 (i didn't understand how switch mode works...now i do...but i have ds2711). I've contacted maxim support and i asked this problem ... with those two pins etc... I hope i will get an answer.

If i still can't build a charger with DS2711 .... MAX712 is tested and very good ...but it doesn't have that top off charging mode. It has only fast...and trickle charge. I still think that .... for my needs, DS2711 is better.

If u think u have time u can try build this MAX712...713. I've attached the files and with all the explications in the file attached.
I will also put here the result ... for my DS2711 . I hope it will work with some help from the maxim's support group

 

[Microemission]

ic regulator built in pinouts

I was also very suspicious of Maxim's free samples in the beginning too
I will surely build the Max712/713 version for a smart charger with your schematics when I have some time.
Hope you hear from Maxim's suport abou the DS2711, as the top off charging mode was what it interested me on this IC too and was hoping that someday I'd put it to work too.

 

[bbogdan]

maxim 713 charger

Ok.... Dallas Semiconductor is a nice company .. very serious.
They've responded in one day

I cannot say your suggested circuit will work without trying it, but yes that is the idea.
I have attached a reference schematic for a circuit that will also work for the DS2712 and is configurable to run in 1 cell, 2S, or 2P configuration. You can use the regulator circuit boxed in for the 2711, it is very similar to what you emailed me.

M* M*

Battery Management Applications

Dallas Semiconductor

And he send me the PDF attached below. But....i didn't really understood it . I can't say what is with those connectors...with A and B (probably one setting is all A... and another all B ... but i'm not sure). i will study it...i've just received the email.

 

[Microemission]

fcx718 equivalent

At lesat they have good support!!
I also don't understand very well what those connecters do either
But I'll also analyse it when i have some more free time.

 

[bbogdan]

max712 problem trickle mode

For those who wonder what have i done with the charger... well it works perfectly. It is based on the schematic i've received from MAXIM (CLICK to download)... BUT don't expect any results from it if you don't have a good power source. (1 REAL Amp output will work fine for the default spects)

Also consider this > https://www.filebam.com/download/79118-94d32f/DS2711-12K.pdf

 

[aetosa]

Re: max712 problem trickle mode

For those who wonder what have i done with the charger... well it works perfectly. It is based on the schematic i've received from MAXIM (CLICK to download)... BUT don't expect any results from it if you don't have a good power source. (1 REAL Amp output will work fine for the default spects)

Also consider this > https://www.filebam.com/download/79118-94d32f/DS2711-12K.pdf

The links are not working, could you please repost the charger.zip file?