BA1442A Rohm, BA1442A Datasheet
BA1442A
Available stocks
Related parts for BA1442A
BA1442A Summary of contents
Page 1
... AM radio / FM IF stereo system IC BA1442A The BA1442A radio and FM IF stereo system IC developed for radio cassette players. The FM circuit is com- prised of a differential IF amplifier, a double-balance type quadrature detector, and a PLL-type stereo MPX circuit. The AM circuit is comprised of a local oscillator, a double-balanced mixer amplifier, a detector, and an AGC circuit. ...
Page 2
... Audio ICs FBlock diagram FPin descriptions 338 BA1442A ...
Page 3
... Audio ICs BA1442A 339 ...
Page 4
... Audio ICs 340 BA1442A ...
Page 5
... Audio ICs FElectrical characteristics (unless otherwise noted 25_C, V 400Hz modulation, 22.5kHz dev (30%), 19kHz 7.5kHz dev (10%) AM: fin = 1000kHz 400Hz 30%) FMeasurement circuit = 5V MPX: fin = 10.7MHz, CC BA1442A 341 ...
Page 6
... Both amplifiers use capacitors to block DC, so bypass capacitors are not necessary. The first stage amplifier has AGC. The gain of this stage is 47dB, and the input impedance (6) AM detector circuit A built-in envelope detector that uses a minute current serves as the AM detector. External components are not required. BA1442A ...
Page 7
... The input / output gain for both AM and FM is about 6dB. The VCO has been laser trimmed on the chip to set its time constant. External components and re-adjustment are not required. BA1442A 343 ...
Page 8
... Audio ICs FFrequency data FComponent data 344 BA1442A ...
Page 9
... Audio ICs BA1442A 345 ...
Page 10
... Connect the earth point to a GND other than the ). CC input side GND. Characteristic curves for different values ) are given in the graph in Fig The 9 form a high The 10 form a high-pass 10 BA1442A ) 12 form a low- 12 ...
Page 11
... Pin 15 is used by both the MPX pilot filter and the AM AGC filter. Lower values for C THD for bass-region AM audio, and larger values will in- crease the time required to switch between monaural and stereo for FM. Characteristic curves for various val- ues BA1442A , C , and will result in increased 17 are given in Figs 347 ...
Page 12
... If the shortwave oscillation startup characteristics are poor, connect an additional resistor (47 with the coil. Make the earth point for the oscillator coil pin 19 (Vreg). The relationship between the ratio and sensitivity at 20dB against pin 20 oscillation voltage is shown in Fig. 11. BA1442A 18 ) and 100 ) in series ...
Page 13
... Even if you will not use AFC, when recovering the sub- carrier phase-modulated composite signal (voice-multi- plexed TV) in the next stage, match the oscillator and “S” curve orientations in the same way as described above. If they are reversed, the left and right channels of the re- covered audio will be reversed. BA1442A 349 ...
Page 14
... Audio ICs FQuiescent pin voltages (V = 5V) CC FElectrical characteristic curves MW characteristics 350 BA1442A ...
Page 15
... Audio ICs FM characteristics BA1442A 351 ...
Page 16
... Audio ICs FApplication board 352 BA1442A ...
Page 17
... Audio ICs FExternal dimensions (Units: mm) BA1442A 353 ...