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How the 8086 processor handles power and clock internally

Accepted submission by Anonymous Coward at 2020-08-15 16:26:47
Hardware

http://www.righto.com/2020/08/how-8086-processor-handles-power-and.html [righto.com]

One under-appreciated characteristic of early microprocessors is the difficulty of distributing power inside the integrated circuit. While a modern processor might have 15 layers of metal wiring, chips from the 1970s such as the 8086 had just a single layer of metal, making routing a challenge. Similarly, clock signals must be delivered to all parts of the chip to keep it in synchronization.

The photo below shows the 8086's die under a microscope. The metal layer on top of the chip is visible, with the silicon substrate and polysilicon wiring hidden underneath. Around the outside of the die, tiny bond wires connect pads on the die to the external pins. The 8086 has a power pad at the top and ground pads at the top and bottom. Each power and ground pad has two bond wires connected to support twice the current. You can see the wide metal traces from the power and ground pads; these distribute power throughout the chip.


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