BA1448S

Audio ICs AM radio / FM IF stereo system IC BA1448S / BA1449F The BA1448S and BA1449F are electronic tuning system ICs for AM, FM IF, and MPX. They have been developed for use in radio cassette players and mini-component stereo systems. The FM detector and MPX VCO circuits do not require adjustment, which will reduce the number of assembly line processes. In particular, the VCO is laser locked, and requires no adjustment or external components. The characteristics of the two chips are the same, but the packages are different (24-pin SDIP for the BA1448S and 24-pin SOP for the BA1449F). FApplications Synthesized tuners in radio cassette players and minicomponent stereo systems. FFeatures 1) Built-in mono AM radio, FM IF amplifier / detector, and FM stereo demodulator. 2) DTS compatible (both SD and IF count). 3) Built-in reference voltage supply for good short-wave band frequency stability. 4) Good FM stability. 5) FM detector does not require adjustment (ceramic discriminator). 6) FM MPX VCO is laser locked and requires no adjustment or external components. 7) Built-in forced monaural function for the MPX (VCO stops, LED off). 8) Audio can be low-cut to improve AM fidelity. 9) VCO for the MPX switches off during AM operation. 10) Mute possible for IF request. FAbsolute maximum ratings (Ta = 25_C) FRecommended operating conditions (Ta = 25_C) 354 Audio ICs FBlock diagram BA1448S / BA1449F 355 Audio ICs FInput / output circuits BA1448S / BA1449F 356 Audio ICs BA1...