byuu's message board

For discussion of projects related to www.byuu.org/


Previous  1, 2, 3, 4  Next
reverse engineering: request for chip donations 
Author Message

Joined: Thu 02 Jun 2011, 01:36:41

Posts: 380
Location: Oklahoma, USA
Post Re: reverse engineering: request for chip donations
vxbinaca wrote:
...... You dont use a heat gun to remove SMD components. Use a soldering iron with a special canted tip, flux, wick and Chip Quik to keep the solder molton.

You will ruin the part removing it improperly. I have a dead board with good PPUs ill tool up and pull them if youd like but youll have to wait a mo

They demonstrate how easy it is here: https://www.youtube.com/watch?v=FTQqjggeklo


Heat guns are the standard really. Especially when you get to BGA's or QFN or other leadless parts.

Sun 18 Nov 2012, 16:29:39
User avatar

Joined: Tue 13 Sep 2011, 14:54:16

Posts: 779
Post Re: reverse engineering: request for chip donations
Caedhros wrote:
vxbinaca wrote:
...... You dont use a heat gun to remove SMD components. Use a soldering iron with a special canted tip, flux, wick and Chip Quik to keep the solder molton.

You will ruin the part removing it improperly. I have a dead board with good PPUs ill tool up and pull them if youd like but youll have to wait a mo

They demonstrate how easy it is here: https://www.youtube.com/watch?v=FTQqjggeklo


Heat guns are the standard really. Especially when you get to BGA's or QFN or other leadless parts.


A heat gun is this:

Image

This is a SMD re-work station:

Image

This is a BGA rework station:

Image


When removing components like that you just want to heat the leads, not the rest of the part. Hence, canted tip on soldering station, lots of flux, chip quik and wick.


Edit: I'll have the chips off mid-December. My old tips ran away and I'm moving.

_________________
Why does Link's uncles house have only one bed if they live together?

Sun 18 Nov 2012, 21:34:48

Joined: Thu 02 Jun 2011, 01:36:41

Posts: 380
Location: Oklahoma, USA
Post Re: reverse engineering: request for chip donations
I'm well aware of how to do that, and what all the tools are. I've been doing that stuff for a living for 12 years now.

Sun 18 Nov 2012, 22:03:23
User avatar

Joined: Mon 20 Apr 2009, 08:11:50

Posts: 5266
Location: 日本
Post Re: reverse engineering: request for chip donations
vxbinaca wrote:
Caedhros wrote:
Heat guns are the standard really. Especially when you get to BGA's or QFN or other leadless parts.


When removing components like that you just want to heat the leads, not the rest of the part.

Image

_________________
CaptainJistuce: He's totally in the wrong, Kakashi's 100% in the right.
Note: The above statement is subject to act of byuu.

Mon 19 Nov 2012, 01:04:02
User avatar

Joined: Tue 31 Aug 2010, 18:53:03

Posts: 424
Location: Somewhere, Texas
Post Re: reverse engineering: request for chip donations
If you have to use a heat gun some control can be added to the process by using kapton tape as a heat shield for parts you want to protect. More effective is a small piece of cardboard wrapped with tape. Even so, heat guns should really only be used for removing bad parts destined for the trash bin.

_________________
I didn't do it, nobody saw me do it, you can't prove anything.

Mon 19 Nov 2012, 03:02:07

Joined: Sun 25 Apr 2010, 06:35:24

Posts: 773
Post Re: reverse engineering: request for chip donations
byuu wrote:
Much the same way as no Japanese cart was made in Mexico :P
I don't actually know of any MAXI-/MJSC- Japanese boards.


Probably won't find any, unlike you find a Japanese equivalent publisher to Majesco.

(yes, obvious answer)

Mon 19 Nov 2012, 03:22:51

Joined: Fri 10 Apr 2009, 22:30:48

Posts: 3797
Location: Salem, Oregon
Post Re: reverse engineering: request for chip donations
would the SMD re-work station be a less volatile solution than a heat gun? How much would such a thing cost?

I am ok with just cutting out the part of the board and letting the decapper deal with it, but i'm not sure if they are counting on me to do that or not, otherwise why wouldn't they have just shipped the SNES directly to him instead of to me.

I think if I'm careful I can take it off with a soldering iron, I just want to know all my options and it sounds like other options are available, although the heat gun looks like it doesn't provide heat as finely as a soldering iron so that defeats the purpose.

something like that SMD re-work station that can (I am guessing) supply heat to very specific locations might be better, but I'm not sure.

What does D have to say? How do I even know if I've killed the chips or not? is there any way for me to know?

_________________
Krita Kickstarter -- https://www.kickstarter.com/projects/kr ... erate-deve

Mon 19 Nov 2012, 03:56:37

Joined: Thu 02 Jun 2011, 01:36:41

Posts: 380
Location: Oklahoma, USA
Post Re: reverse engineering: request for chip donations
Unless you heat them so much they start to melt/bubble it's unlikely you'd be able to tell if there was damage. A SMD rework station like he pictured would cost hundreds unless you find a cheapo brand. The main difference between a heat gun and a rework station is that the station has different nozzles you can put on it to direct the heat. You can get fine points, large ones, and even square ones with small fins on the edges designed specifically for QFP chips like SNES uses. Those aren't cheap either.

EDIT-http://www.picokit.com.au/Store/index.php?route=product/product&product_id=36

Example one...and those prices are alot cheaper than I'm used to, but it's not a brand I know, so who knows on the quality. Also says Australia only so I'm not sure on the currency.

Mon 19 Nov 2012, 04:09:50
User avatar

Joined: Tue 02 Nov 2010, 01:00:37

Posts: 181
Post Re: reverse engineering: request for chip donations
A good SMD rework station will set you back quite a lot. At work, we use a JBC JT-2A, which goes for 1.3 k€... Though you can find good stations for a few hundred bucks. Anything under a hundred will likely be as good as your hair drier (speaking from experience here :( ).

But honestly, if you're going to send it to a decapper anyway, just cut the leads off using pliers or a dremel or something. Be sure not to pull on the leads and be sure not to put too much physical stress onto the cpu. Assuming it's DIP/SOIC-sized (google tells me yes), of course.

Cutting out the part of the board is going to be a pain for the decapper to remove, I think. Except if you send like half the PCB. The leads are in the way when decapping anyway, so it's not like anything is lost.

Also, at work we regularly use heat guns for passive components like connectors and such. Reworking those things when they're soldered at the sides is usually impossible, even when using an oven (and think of the plastic when using the oven)!

cYa,

Tauwasser

Mon 19 Nov 2012, 04:15:55

Joined: Fri 10 Apr 2009, 22:30:48

Posts: 3797
Location: Salem, Oregon
Post Re: reverse engineering: request for chip donations
so just cut the pins off of the board, as close down to the board as possible but without stressing the chip in any way.

_________________
Krita Kickstarter -- https://www.kickstarter.com/projects/kr ... erate-deve

Mon 19 Nov 2012, 04:31:23

Joined: Thu 02 Jun 2011, 01:36:41

Posts: 380
Location: Oklahoma, USA
Post Re: reverse engineering: request for chip donations
Honestly for decap purposes, all they need is the plastic chip body. They are going to use acids to eat off the plastic down to the silicon, and photograph it from there. The leads are unimportant, and unless you have a gorilla do the work for you, it's not likely you will damage the chip internals by cutting the leads.

Mon 19 Nov 2012, 04:34:04
User avatar

Joined: Mon 20 Apr 2009, 08:11:50

Posts: 5266
Location: 日本
Post Re: reverse engineering: request for chip donations
I hear Dr. Decapitator is human.

_________________
CaptainJistuce: He's totally in the wrong, Kakashi's 100% in the right.
Note: The above statement is subject to act of byuu.

Mon 19 Nov 2012, 05:50:14

Joined: Thu 02 Jun 2011, 01:36:41

Posts: 380
Location: Oklahoma, USA
Post Re: reverse engineering: request for chip donations
Kakashi wrote:
I hear Dr. Decapitator is human.


Orly?

Mon 19 Nov 2012, 06:14:16
User avatar

Joined: Tue 13 Sep 2011, 14:54:16

Posts: 779
Post Re: reverse engineering: request for chip donations
Caedhros wrote:
Honestly for decap purposes, all they need is the plastic chip body. They are going to use acids to eat off the plastic down to the silicon, and photograph it from there. The leads are unimportant, and unless you have a gorilla do the work for you, it's not likely you will damage the chip internals by cutting the leads.


That crossed my mind a few hours after my past post. Just use a Exacto knife and slice off all the traces at the PCB.

_________________
Why does Link's uncles house have only one bed if they live together?

Wed 21 Nov 2012, 01:37:10

Joined: Fri 10 Apr 2009, 22:30:48

Posts: 3797
Location: Salem, Oregon
Post Re: reverse engineering: request for chip donations
so... I just got a second SNES in the mail, how many am I supposed to be getting?

_________________
Krita Kickstarter -- https://www.kickstarter.com/projects/kr ... erate-deve

Thu 22 Nov 2012, 07:26:53
Previous  1, 2, 3, 4  Next

Who is online

Users browsing this forum: No registered users and 0 guests

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum