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Can you please send me your schematic for review?  Also the operating conditions such as Vin, # of cells…etc.

-Tahar

Hey Tahar,

Thanks for the quick reply.

Attached is my schematics and an excel file with all the details.

Currently, when I connect adapter(Battery not connected), PG Led comes up and everything looks fine.Then When I connect the battery(with adapter connected), PG Led starts blinking as soon as the charging led start glowing.While debugging I found that Q2(Refer to the schematics attached) starts turning ON and OFF (Vgs becomes positive and then negative and this keeps happening).

Also, this stops when I remove Q5(refer to attached schematics) from the circuit.

Would really appreciate your help!

Karan 

Schematics : http://dl.dropbox.com/u/61043477/bq24617rget%20circuit.png

Excel File : http://dl.dropbox.com/u/61043477/Data%20medi%20charger%20circuit%20v1.0.xls

Hi Karan,

Make sure  you set R8 and R7 correctly for the correct fast charge current, I can not ready the value from the schematic, but based on the attached spread sheet it is set for 6Amp and in the post says 10Amps.

 Also what happens to the adapter voltage, SYS and Battery as the battery is attached. Does the adapter voltage drops? What the currents IN, OUT and BAT? What happen to VCC and Vref voltages?

 Just looking at the schematic (not clear to me) hopefully, the cap on pin 8 is connected to ground.

 What is the voltage on TS pin? If battery temperature is outside desired range, the controller suspends charge and the safety timer, and waits until the battery temperature is within the VLTF to VHTF range.   

-Tahar

Hi Karan,

 Any updates from your side? The schematic is no longer in the drop box.

 -Tahar

HI Tahar,

thanks for reply .sorry for late reply

now the chip is charging the battery with 7.5 amp .

ic is getting much heated is it an normal thing?

and i set values for 6 amp and its charging @7.5amp is thier issue in that..?

Hi Karan,

The IC should handle up to 10Amps. It can be adjusted using equation 2 from the datasheet.

 Regarding the heat, it all depends what you call hot (125C). Please consider the layout recordation especially on the thermal pad. It is critical that the exposed thermal pad on the back side of the IC package be soldered to the PCB ground. Ensure that there are sufficient thermal vias directly under the IC, connecting to the ground plane on the other layers.

 How about the termination issue, is it solved yet ?

 -Tahar

termination issue is solved now...

thanks Tahar for your support....