Intel 8284
The Intel 8284A situated on a motherboard next to a crystal oscillator.
Pinout 8284
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. The industrial version, rated for more extreme temperatures and supply voltages, was priced at $13.50 USD.[1][2][3][4]..
Function
The 8284 contains a clock generator capable of a third the frequency of the input clock (up to 8MHz with the 8284A), with sources selectable between an external crystal and clock input. The main clock output consists of a 4.5V (Vcc @ 5V) square 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 and IBM PC XT.
References
^ alldatasheet.com. "8284 Datasheet". pdf1.alldatasheet.com. Retrieved 2016-11-26..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output .citation q{quotes:"""""""'""'"}.mw-parser-output .citation .cs1-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .citation .cs1-lock-limited a,.mw-parser-output .citation .cs1-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .citation .cs1-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/12px-Wikisource-logo.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{font-size:100%}.mw-parser-output .cs1-maint{display:none;color:#33aa33;margin-left:0.3em}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
^ alldatasheet.com. "UPB8284AD Datasheet". pdf1.alldatasheet.com. Retrieved 2016-11-26.
^ The 8086 Family: Concepts and realities, Intel Preview Special Issue: 16-Bit Solutions, Intel Corporation, May/June 1980, page 19.
^ 8086 Available for industrial environment, Intel Preview Special Issue: 16-Bit Solutions, Intel Corporation, May/June 1980, page 29.
