LM3189 Datasheet | National Semiconductor

LM3189 FM IF System April 1987 LM3189 FM IF System General Description The LM3189N is a monolithic integrated circuit that provides all the functions of a prehensive FM IF system The block diagram of the LM3189N includes a three stage FM IF amplifier limiter configuration with level detectors for each stage a doubly balanced quadrature FM detector and an audio amplifier that Features the optional use of a muting (squelch) circuit The advanced circuit design of the IF system includes desirable deluxe Features such as programmable delayed AGC for the RF tuner an AFC drive circuit and an output signal to drive a tuning meter and or provide stereo switching logic In addition internal...