thats an awesome idea. I’ve always been interested in the Jordana PC’s and one thing that holds them back is lack of USB functionality which even my old libretto 110CT has (abeit in a base unit)

That is made of awesome and cool. I actually have located JTAG pins on BGA CPUs like this, but I always measured out the length of the wire beforehand and eyeballed where the ball must be. Using a toothbrush-bristle should make that job a bit easier.

This is awesome.

That is a great way to probe.
Far better than sacrificing a device and remove the BGAs and other parts in order to trace the pins.

Thanks for this simple but very useful method.

Regards,

EqX

wow, don’t know if ill try that anytime soon but that’s really clever.

i have in the past just pushed the very thin wire
all the way through under the chip.
then bent the end of the wire on the “far end”
towards the side of the ball row wanted .
making sure the enamel is intact on the other
(making sorta spring between the two ball rows)

and then pulled it back a number of balls
feeling the “bumps” as it passes the balls.
(like picking a lock) till it gets to the right one.
then a certain amount of tension is possible
before it “bumps too far”

fixate the wire with hotglue
and start “beeping”

then dubble / tripple check ;)

Good mod, but if someone knows how to add an usb functionality to a wifi router.

@Rune kyndal

“im having a hard time locating datasheet for it. …anybody have the real datasheet for bcm4712 ??”

Good luck. People have been trying for years to get it and Broadcom is not budging.

rd & Rune kyndal-
Call that one “Bumps Too Far” and start compiling your book of technopoetry. It’s like beatnik percussive, man.

he he.. that’s funny guys.\n
but hey Poetry or not. \n
that way i have beeped the usb pinout of the \n
BCM4712KFB-0445-P12 \n
and im working on locating pads and vias for them (hopefully)\n
as its a pain to access balls underneath a bga!\n
\n

Datasheet from Broadcom ? LOL LOL LOL
Sorry. Broadcom is the most hobbyist unfriendly company that exist. I have tried to get datasheets from them for products made 10 years ago and no longer used. Even if I agreed to sign an NDA they wouldn’t let me view them . That is why if I am buying hardware like a router or set top box I check to see if broadcom is involved. If they are I buy something else.

@samurai

I don’t think he’ll risk getting fired.

well.. i got the usb pins. all i need to know is if there is some pins i need to pull low/high to enable the usb. (besides software)

dont really care for the datasheet beyond the
usb pinout
they can keep that Suuuuuuper secret!!!!

Woooooh! Secret chip.

how can secrecy help sales??
Not a clue!

Get in the game OPEN is the word these days!

never underestimate the myraid uses of low melting point alloy and a 1mm syringe needle.. :)

in this case feeding a wire with ~.5mm diameter LMP alloy ball onto the desired ball or pad and using heat applied to the needle to “weld” it in place without disrupting the rest of the joint.

another handy trick is to preheat the section to be modded up to about 100 Celsius (use the thermal pad from a deceased plasma panel backplane for this) before doing the mod, reduces strain on the PCB.

inspired by those 1337 folks at intel with their chip bonding machines…

I use a method similar to Rune kyndal. I don’t just count bumps, however. I x-ray. Not everyone has such a tool, but I’m glad as hell I do.

In my case I need it because there are times I’ll reflow the BGA with hot air to keep the wire in place. You don’t want to chance it when you could very well hose the BGA if the solder pulls to an adjacent ball when reflowed.