How to identifiy IC manufacturers of semiconductor devices used in vintage Apple systems
With the insatiable personal computer demand of the 80's came the semiconductor supply boom, which was felt around the entire globe, especially in Asia and the US. Constant shortages of various devices opened up new opportunities for manufacture and supply of the much needed devices, and also established the major technology centres around the world today. Although some counterfeiting of devices was known at the time, most major semiconductor vendors were quick to construct multi-million dollar high technology facilities in many countries, such as England, Portugal, Malaysia, El Salvador, Taiwan, Ireland, Japan, Korea, Singapore, Indonesia, Mexico, Brazil, Thailand, Philippines, Malta, Italy and the USA to supply the lucrative technology markets. For over a decade the LS, or discreet logic series, enjoyed tremendous success, being the core ingredient of most computer designs of that time. By the mid 1990's a transition to ASSP, ASIC and the matured FPGA and CPLD devices had well and truly begun. By 1998 the demand had completely fallen off for standard logic, and was fast becoming extinct to newer, cheaper, faster, smaller, and more flexible integrated devices. With the pursuing economic changes, maintaining and operating many semiconductor fabrication and packaging sites simply became not economically viable. Only a few discreet logic vendors remain today. Many became extinct, whilst others transitioned into new device technologies. The following photos illustrate a snapshot in history as to what each company's devices once looked liked; while many still use the same logo, such as TI and AMD, others evolved their logos into something else, such as GoldStar, or simply left the semiconductor industry altogether.
The semiconductor industry's standard date stamp
Classic logic vendors of the eighties
For the majority of the time the semiconductor industry has been producing devices, a date code system has been in place and used by most vendors as far back as 1969. The very generic concept of "YEAR-WEEK" is still in use on most devices produced today. By representing the date of manufacture as four digits, two for the year and two for the week number, each device can have its vintage easily identified. Although this system is primarily used for identifying manufacturing batches in quality control, the time stamp makes a very useful tool in determining the age of a product the device is used in. With Apple II clones, this is the only method, as most PCB's had no markings at all.
Motorola's DRAM memory controller, manufactured during the peak of the industry, in the 15th week of 1980.