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Should Buyer purchase or use ON Semiconductor products for any such unintended or unauthorized application, Buyer shall indemnify and hold ON Semiconductor and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that ON Semiconductor was negligent regarding the design or manufacture of the part. ON Semiconductor is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.FST3253 Dual 4:1 Multiplexer/Demultiplexer Bus Switch September 1997 Revised December 1999 FST3253 Dual 4:1 Multiplexer/Demultiplexer Bus Switch General Description Features The Fairchild Switch FST3253 is a dual 4:1 high-speed 4 switch connection between two ports. CMOS TTL-compatible multiplexer/demultiplexer bus Minimal propagation delay through the switch. switch. The low on resistance of the switch allows inputs to Low l . CC be connected to outputs without adding propagation delay Zero bounce in flow-through mode. or generating additional ground bounce noise. Control inputs compatible with TTL level. When OE is LOW, S and S connect the A Port to the 0 1 selected B Port output. When OE is HIGH, the switch is OPEN and a high-impedance state exists between the two ports. Ordering Code: Order Number Package Number Package Description FST3253M M16A 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow FST3253QSC MQA16 16-Lead Quarter Size Outline Package (QSOP), JEDEC MO-137, 0.150 Wide FST3253MTC MTC16 16-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide Device also available in Tape and Reel. Specify by appending suffix letter X to the ordering code. Logic Diagram Connection Diagram Truth Table S S OE OE Function 1 0 1 2 Pin Descriptions X X H X Disconnect 1A Pin Name Description X X X H Disconnect 2A L LLL A = B OE , OE Bus Switch Enables 1 1 2 LH L L A = B S , S Select Inputs 2 0 1 H LLL A = B ABus A 3 HH L L A = B B , B , B , B Bus B 4 1 2 3 4 1999 Fairchild Semiconductor Corporation DS500058 www.fairchildsemi.com