8251A © 2012 Rochester Electronics, LLC. All Rights Reserved 12192012 ynchronous Receiver/Transmitter (USART) The 8251A is the industry standard Universal Synchronous/As such as MCS-48, 80, 85, and iAPX 86, 88. designed for data communications with microprocessor families CPU to operate using virtually any serial the by med program is and device al peripher The 8251A is used as a ). The USART accepts data characters “bi-sync” IBM g data transmission technique presently in use (includin us serial data stream for transmission. continuo a into them converts then and format parallel in from the CPU parallel data characters for the CPU. into them convert and streams Simultaneously, it can receive serial data for transmission or whenever it has r characte The USART will signal the CPU whenever it can accept a new of the USART at any time. These status complete the read can CPU The CPU. the received a character for Y. The chip is fabricated using TxEMPT , SYNDET as such include data transmission errors and control signals gy. technolo HMOS nce performa Intel’s high * For complete Rochester ordering guide, please refer to page 2 * Rochester Electronics guarantees performance of its semiconductor products to the original OEM specifications. “Typical” values are for reference purposes only. Certain minimum or maximum ratings may be based on product characterization, design, simulation, or sample testing. Rochester Electronics reserves the right to make changes without further notice to any specification herein. Specification Number 8251A-CI (I) REV A Page 1 of 11 8251A Rochester Ordering Guide Package Temperature D8251A Rochester Part Number D8251A OCM Part Number DIP-28 0° to +70°C ID8251A ID8251A DIP-28 -40° to +85°C LD8251A LD8251A DIP-28 -40° to +85°C P8251A P8251A DIP-28 0° to +70°C QD8251A QD8251A DIP-28 0° to +70°C QP8251A QP8251A DIP-28 0° to +70°C TD8251A TD8251A DIP-28 -40° to +85°C Specification Number 8251A-CI (I) REV A Page 2 of 11 8251A Specification Number 8251A-CI (I) REV A Page 3 of 11 8251A Specification Number 8251A-CI (I) REV A Page 4 of 11 8251A Specification Number 8251A-CI (I) REV A Page 5 of 11 8251A Specification Number 8251A-CI (I) REV A Page 6 of 11 8251A Specification Number 8251A-CI (I) REV A Page 7 of 11 8251A Specification Number 8251A-CI (I) REV A Page 8 of 11 8251A Specification Number 8251A-CI (I) REV A Page 9 of 11 8251A Specification Number 8251A-CI (I) REV A Page 10 of 11 8251A Rochester Electronics guarantees performance of its semiconductor products to the original OEM specifications. “Typical” values are for reference purposes only. Certain minimum or maximum ratings may be based on product characterization, design, simulation, or sample testing. Rochester Electronics reserves the right to make changes without further notice to any specification herein. Specification Number 8251A-CI (I) REV A Page 11 of 11