Is Now Part of To learn more about ON Semiconductor, please visit our website at www.onsemi.com ON Semiconductor and the ON Semiconductor logo are trademarks of Semiconductor Components Industries, LLC dba ON Semiconductor or its subsidiaries in the United States and/or other countries. ON Semiconductor owns the rights to a number of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of ON Semiconductors product/patent coverage may be accessed at www.onsemi.com/site/pdf/Patent-Marking.pdf. ON Semiconductor reserves the right to make changes without further notice to any products herein. ON Semiconductor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does ON Semiconductor assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. Buyer is responsible for its products and applications using ON Semiconductor products, including compliance with all laws, regulations and safety requirements or standards, regardless of any support or applications information provided by ON Semiconductor. Typical parameters which may be provided in ON Semiconductor data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including Typicals must be validated for each customer application by customers technical experts. ON Semiconductor does not convey any license under its patent rights nor the rights of others. ON Semiconductor products are not designed, intended, or authorized for use as a critical component in life support systems or any FDA Class 3 medical devices or medical devices with a same or similar classification in a foreign jurisdiction or any devices intended for implantation in the human body. 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.FST3126 4-Bit Bus Switch August 1997 Revised January 2005 FST3126 4-Bit Bus Switch General Description Features The Fairchild Switch FST3126 provides four high-speed 4 switch connection between two ports. CMOS TTL-compatible bus switches. The low on resis- Minimal propagation delay through the switch. tance of the switch allows inputs to be connected to out- Low l . CC puts without adding propagation delay or generating Zero bounce in flow-through mode. additional ground bounce noise. Control inputs compatible with TTL level. The device is organized as four 1-bit switches with sepa- rate OE inputs. When OE is HIGH, the switch is ON and Port A is connected to Port B. When OE is LOW, the switch is OPEN and a high-impedance state exists between the two ports. Ordering Code: Order Number Package Number Package Description FST3126M M14A 14-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow FST3126QSC MQA16 16-Lead Quarter Size Outline Package (QSOP), JEDEC MO-137, 0.150 Wide FST3126MTC MTC14 14-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide Devices also available in Tape and Reel. Specify by appending the suffix letter X to the ordering code. Logic Diagram Connection Diagrams Pin Assignment for SOIC and TSSOP Pin Assignment for QSOP Pin Descriptions Pin Name Description Truth Table OE , OE , OE , OE Bus Switch Enables 1 2 3 4 1A, 2A, 3A, 4A Bus A Inputs Inputs/Outputs 1B, 2B, 3B, 4B Bus B OE A,B NC Not Connected LZ HA = B 2005 Fairchild Semiconductor Corporation DS500044 www.fairchildsemi.com