LM1865N National Semiconductor, LM1865N Datasheet
LM1865N
Specifications of LM1865N
LM1865
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LM1865N Summary of contents
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... User control of both AGC thresholds Y Excellent signal to noise ratio AM rejection and system Y limiting sensitivity Order Number LM1865M or LM1865N See NS Package Number M20B or N20A FIGURE 1 February 1995 TL H 7509 – 1 RRD-B30M115 Printed ...
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... Absolute Maximum Ratings If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications Supply Voltage Pin 17 Package Dissipation (Note 1) Storage Temperature Range b Operating Temperature Range Max Voltage on Pin 16 (Stop Output) Electrical Characteristics Test Circuit T ...
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Electrical Characteristics position 2 unless indicated otherwise (Continued) Parameter DYNAMIC CHARACTERISTICS f 400 MOD Pin 13 Mute Stop Threshold Voltage Amount of Muting (LM1965 Only) Amount of Muting with Pin 13 and Pin 16 Grounded Narrow Band ...
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Typical Performance Characteristics FM Limiting Characteristics and AM Rejection % THD vs OFF Tuning (Single Tuned Quadrature Coil) Coils and ceramic filters are available from Toko America Murata 1250 Feehanville Drive 2200 Lake Park Drive Mount Prospect IL 60056 Smyrna ...
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Application Circuit IC External Components (See Application Circuit) Component Typical Value ...
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Typical Application LAYOUT CONSIDERATIONS Although the pinout of the LM1865 has been chosen to min- imize layout problems some care is required to insure sta- bility The ground terminal on CF1 should return to both PERFORMANCE CHARACTERISTICS OF TYPICAL APPLICATION ...
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Application Notes ADJUSTABLE MUTE STOP THRESHOLD The threshold adjustments for the mute and stop functions are controlled by the same pins Thus the term mute stop will be used to designate either function The adjustable mute stop threshold in the ...
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Application Notes (Continued) STOP TIME An electronically tuned radio (ETR) pauses at fixed intervals across the FM band and awaits the stop indication from the LM1865 If within a predetermined period of time no stop indication is forthcoming the controller ...
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Application Notes (Continued) The LM1865 has been carefully designed to insure low AFT offset current at the point of minimum THD AFT offset cur- rent will cause a non-symmetric deviation mute stop win- dow about the point of minimum THD ...
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Application Notes (Continued) First examine what happens with a single in-band signal as we vary the strength of this signal Figures 6 and 7 illustrate what happens at the tuner and AGC outputs FIGURE 6 FIGURE 7 Prime indicates referenced ...
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Application Notes (Continued) voltage while V is allowed to increase V D until it reaches the level of the wide band threshold at the tuner output When this occurs longer needed to UD keep ...
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Application Notes (Continued) WIDE BAND AGC THRESHOLD ADJUSTMENT There are a number of criteria that determine where the wide band threshold should be set If the threshold is set too high protection against IM will be lost If the threshold ...
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Application Notes (Continued) In order to make the calculation in equation (4) the con- stants must first be determined This is done by the following procedure 1 Connect together two RF generators and apply them to the ...
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Simplified Diagram 14 ...
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Physical Dimensions inches (millimeters) Small Outline IC Package (M) Order Number LM1865M NS Package Number M20B 15 ...
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... National does not assume any responsibility for use of any circuitry described no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications Molded Dual-in-Line Package (N) Order Number LM1865N NS Package Number N20A 2 A critical component is any component of a life ...