Factory Defect IC Revived With Sandpaper And Microsoldering

-
The decapped chip on top of some other DIP IC, with magnet wire soldered to the die, other ends of the magnet wire soldered to pins of the "body donor" DIP IC.

We might be amidst a chip shortage, but if you enjoy reverse-engineering, there’s never a shortage of intriguing old chips to dig into – and the 2513N 5×7 character ROM is one such chip. Amidst a long thread probing a few of these (Twitter, ThreadReader link), [TubeTime] has realized that two address lines were shorted inside of the package. A Twitter dopamine-fueled quest for truth has led them to try their hand at making the chip work anyway. Trying to clear the short with an external PSU led to a bond wire popping instead, as evidenced by the ESD diode connection disappearing.

A dozen minutes of sandpaper work resulted in the bare die exposed, making quick work of the bond wires as a side effect. Apparently, having the bond pads a bit too close has resulted in a factory defect where two of the pads merged together. No wonder the PSU wouldn’t take that on! Some X-acto work later, the short was cleared. But without the bond wires, how would [TubeTime] connect to it? This is where the work pictured comes in. Soldering to the remains of the bond wires has proven to be fruitful, reviving the chip enough to continue investigating, even if, it appears, it was never functional to begin with. The thread continued on with comparing ROMs from a few different chips [TubeTime] had on hand and inferences on what could’ve happened that led to this IC going out in the wild.

Such soldering experiments are always fun to try and pull off! We rarely see soldering on such a small scale, as thankfully, it’s not always needed, but it’s a joy to witness when someone does IC or PCB microsurgery to fix factory defects that render our devices inoperable before they were even shipped. Each time that a fellow hacker dares to grind the IC epoxy layers down and save a game console or an unidentified complex board, the world gets a little brighter. And if you aren’t forced to do it for repair reasons, you can always try it in an attempt to build the smallest NES in existence!



from Blog – Hackaday https://ift.tt/7ZSuh5MyC

Comments

Post a Comment

Popular posts from this blog

Modern Radio Receiver Architecture: From Regenerative to Direct Conversion

-
Image
Modern radio receivers have a distinct advantage over the common early designs which I covered in my previous article . Most of the receivers you will have worked with over the past couple decades are designs by Edwin Armstrong ; regenerative, superregenerative, or most commonly superheterodyne. These are distinguished by a few fascinating key traits that bring both benefits and drawbacks. Today let’s dive into Mr. Armstrong’s receivers. I’ll also talk about DC receivers which, despite the name, are not made to listen to batteries. These are receivers you are much more likely to encounter in modern equipment. Regenerative and Superregenerative The regenerative receiver is all about doing more with less. You still see some of these in simple applications like RF remote controls. The idea derives from how an oscillator works. In a simple way of thinking, an oscillator is an amplifier with enough positive feedback that any tiny signal at the right frequency will amplify and then, throu...
Get this one»

Hackaday Links: May 31, 2020

-
We begin with sad news indeed as we mark the passing of Marcel van Kervinck on Monday. The name might not ring a bell, but his project, the Gigatron TTL computer , certainly will. We did a deep dive on the microprocessor-less computer a while back, and Marcel was a regular at conferences and on the Gigatron forums, supporting users and extending what the computer can do. He was pretty candid about his health issues, and I’ll add that when I approached him a few weeks ago out of the blue about perhaps doing a Hack Chat about Gigatron, he was brutally honest about how little time he had left and that he wouldn’t make it that long. I was blown away by the grace and courage he displayed. His co-conspirator Walter Belger will carry on the Gigatron mission, including joining us for a Hack Chat on June 24. In the meantime, this might be a great time to pick up a Gigatron kit before they’re all sold out and get busy soldering all those delicious through-hole TTL chips. May of 2020 is the mo...
Get this one»

Homebrew 68K Micro-ATX Computer Runs Its Own OS

-
Image
We’re no stranger to home built Motorola 68000 computers here at Hackaday, but more often than not, they tend to be an experiment in retro minimalism. The venerable processor is usually joined by only a handful of components, and there’s an excellent chance they’ll have taken up residence on a piece of perfboard. Then [NotArtyom] sent in his Blitz , and launched the bar into the stratosphere. Make no mistake, the Blitz isn’t just some simple demo of classic chips. The open hardware motherboard has onboard floppy, IDE, and PS/2 interfaces, with a trio of 8-bit ISA expansion slots for good measure. The  Motorola 68030 CPU is humming along at 50 MHz, with 4 MB of RAM and 512 KB of ROM along for the ride. Designed to fit the Micro-ATX motherboard standard, you can even mount the Blitz in a contemporary PC case and run it on a standard ATX power supply. An earlier prototype of the Blitz motherboard. As if the hardware wasn’t impressive enough, [NotArtyom] went ahead and created hi...
Get this one»