Is Now Part of To learn more about ON Semiconductor, please visit our website at www.onsemi.com Please note: As part of the Fairchild Semiconductor integration, some of the Fairchild orderable part numbers will need to change in order to meet ON Semiconductors system requirements. Since the ON Semiconductor product management systems do not have the ability to manage part nomenclature that utilizes an underscore ( ), the underscore ( ) in the Fairchild part numbers will be changed to a dash (-). This document may contain device numbers with an underscore ( ). Please check the ON Semiconductor website to verify the updated device numbers. The most current and up-to-date ordering information can be found at www.onsemi.com. Please email any questions regarding the system integration to Fairchild questions 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.FOD2743A, FOD2743B, FOD2743C Optically Isolated Error Amplier August 2008 FOD2743A, FOD2743B, FOD2743C Optically Isolated Error Amplifier Features Description Optocoupler, precision reference and error amplifier in The FOD2743 Optically Isolated Amplifier consists of the a single package popular KA431 precision programmable shunt reference and an optocoupler. The optocoupler is a gallium ars- 2.5V reference enide (GaAs) light emitting diode optically coupled to a CTR 50% to 100% at 1mA silicon phototransistor. It comes in 3 grades of reference 5,000V RMS isolation voltage tolerance = 2%, 1%, and 0.5%. UL approval E90700, Vol. 2 The Current Transfer Ratio (CTR) ranges from 50% to CSA approval 1296837 100%. It also has an outstanding temperature coefficient VDE approval pending of 50 ppm/C. It is primarily intended for use as the error BSI approval pending amplifier/reference voltage/optocoupler function in iso- Low temperature coefficient 50ppm/C max lated AC to DC power supplies and dc/dc converters. FOD2743A: tolerance 0.5% When using the FOD2743, power supply designers can FOD2743B: tolerance 1% reduce the component count and save space in tightly FOD2743C: tolerance 2% packaged designs. The tight tolerance reference elimi- nates the need for adjustments in many applications. Applications The device comes in an 8-pin dip white package. Power supplies regulation DC to DC converters Functional Bock Diagram Package Outlines LED 1 8 NC 8 1 COMP 2 7 C 3 6 E GND 8 8 4 5 NC FB 1 1 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com FOD2743A, FOD2743B, FOD2743C Rev. 1.0.1