- Interesting BiCMOS circuits in the Pentium, reverse-engineered (righto.com)
Intel released the powerful Pentium processor in 1993, establishing a long-running brand of processors. Earlier, I wrote about the ROM in the Pentium’s floating point unit that holds constants such as π. In this post, I’ll look at some interesting circuits associated with this ROM. In particular, the circuitry is implemented in BiCMOS, a process that combines bipolar transistors with standard CMOS logic.
- Inside the stacked RAM modules used in the Apple III (righto.com)
In 1978, a memory chip stored just 16 kilobits of data. To make a 32-kilobit memory chip, Mostek came up with the idea of putting two 16K chips onto a carrier the size of a standard integrated circuit, creating the first memory module, the MK4332 “RAM-pak”. This module allowed computer manufacturers to double the density of their memory systems and by 1982, Mostek had sold over 3 million modules. The Apple III is the best-known system that used these memory modules.