The Intel 8284 is a clock oscillator chip developed primarily for supplying clock signals for the Intel-8086/8087/8088/8089 series of processors. The commercial variant of the chip comes in 18-pin DIL and 20-pin PLCC packages, and originally was priced at $4.90 USD.[1][2][3] The industrial version, rated for the temperatures range of -40 °C to +85 °C was priced at $13.50 USD.[4] The available 82C84A CMOS version was outsourced to Oki Electronic Industry Co., Ltd.[5] The available packaged Intel 82C84A version of 20-pin PLCC in sampling at first quarter of 1986.[6]
Function
editThe 8284 contains a clock generator capable of a third the frequency of the input clock (5 or 8MHz with the 8284A, and 10MHz with the 8284A-1), with sources selectable between an external crystal and clock input. The main clock output consists of a 4.5V (Vcc @ 5V) pulse wave at a 33.3% duty cycle, with an additional peripheral clock running at half of the main clock and a 50% duty cycle. Additional logic is provided to accommodate delays to allow for proper system start-up. It has been used in the IBM PC, IBM PC XT and IBM PCjr.
References
edit- ^ Intel Corporation, "The 8086 Family: Concepts and realities", Intel Preview Special Issue: 16-Bit Solutions, May/June 1980, Page 19
- ^ alldatasheet.com. "8284 Datasheet". pdf1.alldatasheet.com. Retrieved 2016-11-26.
- ^ alldatasheet.com. "UPB8284AD Datasheet". pdf1.alldatasheet.com. Retrieved 2016-11-26.
- ^ Intel Corporation, "8086 Available for industrial environment", Intel Preview Special Issue: 16-Bit Solutions, May/June 1980, Page 29
- ^ Intel Corporation, "NewsBit: Intel Licenses Oki on CMOS Version of Several Products", Solutions, July/August 1984, Page 1.
- ^ Ashborn, Jim; "Advanced Packaging: A Little Goes A Long Way", Intel Corporation, Solutions, January/February 1986, Page 2