Unmarked Die Revisions :: Part II
[NOTE- This article will describe a process known as “Wet-Etching“. Wet-etching is a process that can be very dangerous and we do not recommend anyone reading this try it unless you know what you are doing and have the proper equipment. The chemicals required such as Hydrofluoric Acid (HF) attack bone marrow. HF is painless until several hours later when it’s too late to take proper action so please be careful and be responsible. ] Previously we discussed noticing Microchip making changes…
Unmarked Die Revisions :: Part I
We have noticed a few different die revisions on various Microchip’s substrates that caught our attention. In most case when a company executes any type of change to the die, they change the nomenclature slightly. An example is the elder PIC16C622. After some changes, the later part was named the PIC16C622A and there was major silicon layout changes to the newer ‘A’ part. The PIC16C54 has been through three known silicon revs (‘A’ – ‘C’) and has now been replaced by the PIC16F54. However, we’ve noticed two different devices from them (PIC12F683…