Pin Assignment


dpoarch

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I am replacing my ltsk in my gp2x but I got it too hot or something and lifted up to pads while trying to take the old one off. I cannot tell which direction to read the chip but from http://www.linear.com/pc/productDetail.jsp...031,C1060,P1901 it shows it being either vin and shdn or ground and vc. If you are looking at the ltsk on the gp2x it is the top 2 pins on the left. If its ground and vc then from linear's website vc should go through some of the capacitors. If its vin and shdn their example shows them being just wired together connected to vin. It is an f100 and if anyone knows where a schematic is or knows where the legs should be hooked to I would greatly appreciate your help.
 
ok so I was reading the tech doc wrong and now know what pins I messed up. They were 6 & 7 which correspond to the Vout and PGOOD respectively. The tech doc had a typical usage diagram up which hooked Vout to just an output terminal and a 909kohm resistor. The other side of the 909kohm resistor was hooked to pin 8 and a 549kohm resistor which was grounded. Resistor 211 is 913kohm and 212 is 563kohm so I am guessing this is that circuit. What I am not sure is which side of R211 is supposed to be wired to pin 6. I could probably test bench this to find out but it would be a lot easier if someone knew. Another thing is I am not sure where to hook PGOOD. On their example they left it unhooked, but I believe that it is used to tell if the batteries are still good. If this is the case then it may need to be connected to something. Once again any help or comments would be greatly appreciated.
 
I have never open up my GP2X (f100) so I don't know the orientation of the chip based on the dot on pin 1. If you have a (f100) then this picture might help. (looking for it now, will insert link when I find it)

EDIT: I looked over the site and could not find the picture of an F100 opened up which might show the orientation of the chip. Of course if you have a newer model then it would not have helped anyway.
 
This is the only picture I could find http://wiki.gp2x.org/wiki/Image:LTC3402EMS.jpg and the dot is in the lower right corner of the chip with respect to this pic. The 2 resistors to the left of the ltsk right above the arrow are 211 & 212. It looks like R211 abd R212 make a voltage divider that feeds into pin 8 which is FB on the tech doc(I don't know what that stands for).
 
That is pretty much the picture I remember but the picture covered more of the board so I could looks at the different components and see their orientation. With a rev level I am not sure how much help this is to you. I am assuming that you have a f100 at this point since you have not told me otherwise. I was thinking that if someone already has the correct model open they could post a picture on the wiki to help people like you. My machine is locked up at school right now so I can't snap a shot right now. Of course I really do not want to open it up unless their is no other option because I am sure there will be issues getting it back together.
 
ya its an f100 I thought I said so earlier but I must have left it out. The first time you take it apart its kinda weird and I know I was scared that I was gonna break something. Im kinda over that now because it doesn't work at all. Ya I should have used my friends digital slr to snap a pic before I started taking it apart but I wrote down all the resistors and caps and figured that was enough. I didn't think I would destroy to pads like that, but I probably could have prepared myself a little better. I just can't see where the traces from those pads went on my board. It looks like pin 7(vout) runs up to C189 and possibly over to the top of R211, but I cannot be sure. Pin 6(PGOOD) should run to vin through a resistor and to the input of a transistor, But I cannot find this.
 
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