A3845 ALLEGRO [Allegro MicroSystems], A3845 Datasheet
A3845
Related parts for A3845
A3845 Summary of contents
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... This noise blanker integrated circuit contains all of the necessary circuitry for adding an extremely efficient (patented) noise-blanking technique to any type of AM tuner or receiver with RF input frequen- cies (or a first IF MHz. The A3845ELW and A3845SLW feature dual audio channels and are intended for AM-stereo or indepen- dent sideband applications. ...
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AM NOISE BLANKER BYPASS 2 RF BIAS 3 RF AGC 4 GROUND 16 SUPPLY CONNECTION NOISE RF Note that the noise-pulse input is attenuated the test circuit. PEAK ...
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Test Characteristic Leads Supply Voltage Range 20 Quiescent Supply Current 20 RF INPUT AMPLIFIER: Trigger Threshold 1 Modulation Threshold 1 Detector Rise Time 13 RF SWITCH: ON Resistance 17-18 OFF Resistance 17-18 Time Delay 1-17 AUDIO SWITCHES: Attenuation 10-9, 11-12 ...
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... This results in a long blanking time and poor performance at the higher frequencies where a short blanking time is needed most. The A3845xLW takes a different approach to the noise suppression problem by sensing the noise pulse in the receiver’s RF section and blanking the pulse before it reaches the IF. This requires a noise amplifier with a minimum propagation delay and high-speed gating ...
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ANTENNA RF MIXER BW = "WIDE" 20 kHz 0.5 µs 50 µs NOISE PULSE The products described here are manufactured under one or more U.S. patents or U.S. patents pending. Allegro MicroSystems, Inc. reserves the right to make, from time ...
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... The A3845xLW noise blanker can also be used in dual-conversion AM tuners. The blanker RF input would then be connected at the first IF amplifier input and the blanker RF gate connected at the second mixer output. Because ...
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AM NOISE BLANKER ...
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AM NOISE BLANKER 20 0.2992 0.2914 0.020 1 0.013 0.0926 0.1043 0.0040 20 7.60 7.40 0.51 1 0.33 2.65 2.35 0.10 NOTES: 1. Exact body and lead configuration at vendor’s option within limits shown. 2. Lead spacing tolerance is ...