CXA1842S 3-Mode Surround and Vocal Cancellation Description The CXA1842S is a bipolar IC which combines 3mode surround, bass boosting and vocal cancellation function into a single chip. 22 pin SDIP (Plastic) Features • 3-mode surround (surround A, surround B, simulated stereo) • Vocal cancellation function • Bass boosting function Absolute Maximum Ratings (Ta=25°C) • Supply voltage VCC 14 • Operating temperature Topr –20 to +75 • Storage temperature Tstg –65 to +150 • Allowable power dissipation PD 880 Applications CD Radio-cassette tape recorders, equipment with Karaoke functions Structure Bipolar silicon monolithic IC Recommended Operating Conditions Supply voltage VCC 5 to 12 V °C °C mW V Lch IN LPF L1 LPF L2 LPF L3 DET L DET R PSN1 PSN2 GND Vcc Lch OUT Block Diagram and Pin Configuration 22 21 20 19 18 17 16 15 14 13 12 S4 REF S6 S5 VCA DET S2 S.S DET VCA S5 S6 REF S4 Vcc S3 VCA R2 –6 S1 DET SW CONT R1 LPF R2 LPF R3 DET V.C 7 8 9 10 11 Rch OUT LPF R1 6 REF 5 SW2 4 SW1 3 B.B 2 V.C 1 Rch IN REF Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits. —1— E93702-TE CXA1842S Pin Description Pin No. Symbol (VCC=10V, Ta=25°C) Pin Voltage Equivalent Circuit Description Channel L input pin Channel R VCC 1 Rch IN 1 5.0V 129 56K 22 22 Lch IN AGND GND Time constants for L.P.F. 32K 2 21 LPF R1 LPF L1 64K 80K AGND 2 3 20 LPF R2 LPF L2 21 5.0V 3 20 4 19 LPF R3 LPF L3 4 19 Level detector pin. To be connected with a capacitor VCC 5 DET V.C 17 DET R 5 0.5V 129 17 5K 18 18 500 200 200 100K DET L —2— CXA1842S Pin No. Symbol Pin Voltage Equivalent Circuit Description VCC 6 V.C 7 B.B SW is turned ON when this pin is connected to GND VCC — 8 SW 1 6 AGND 129 9 7 SW 2 8 9 Reference voltage (1/2 VCC) VCC 48K 10 10 REF 5.0V AGND 48K GND VCC 11 Rch OUT Channel R output pin Channel L 297 5.0V 11 12 Lch OUT 13 Vcc 10V 14 GND 0 129 297 12 Power supply GND pin The pin to be connected with a capacitor for time constants of phase shift VCC 15 PSN 2 5.0V 16 PSN 1 15 16 —3— CXA1842S Electrical Characteristics (VCC=10V, Ta=25°C) No. Item Conditions 1 2 3 4 5 6 7 8 9 No signal current Lch gain Rch gain Channel balance Lch total harmonic distortion Rch total harmonic distortion Lch noise level Rch noise level Channel separation Vin=GND Vin=2Vrms, f=1kHz ↓ Lch gain - Rch gain Vin=2Vrms, f=1kHz ↓ Vin=GND ↓ Vin=2Vrms, f=1kHz SW conditions S1 S2 S3 S4 S5 S6 O O O O O — — — — — — O O O O O O O O S7 O — O O O Min. Typ. Max. Unit 1.6 -3 -3 -3 — — — — 55 3.35 0 0 0 0.07 0.07 - 90 - 90 63 5.1 mA 3 dB 3 dB 3 dB 0.1 % 0.1 % - 80 dBm - 80 dBm — dB O...indicates “ON”. 18 17 16 15 14 13 12 PSN1 PSN2 GND Vcc Lch OUT V1 19 DET R 10V 0.01µ 2200p 20 DET L C11 21 LPF L3 C10 10µ 22 LPF L2 C9 10µ C8 0.1µ C4 10µ LPF L1 0.022µ C15 10µ Lch IN 10µ C6 10k C12 C2 R4 Electrical Characteristics Measurement Circuit S5 S6 S7 DET V.C V.C B.B SW1 SW2 REF Rch OUT 4 5 6 7 8 9 10 11 V 10µ 10µ —4— 10k C14 R3 10µ S2 S1 S4 S3 C13 0.022µ 10µ C5 C7 3 LPF R3 LPF R2 2 0.1µ LPF R1 1 C3 C1 Rch IN VIN CXA1842S Application Circuit C12 GND C2 22 21 19 18 17 16 C15 10µ 0.01µ 2200p C11 10µ C10 C9 0.022µ 20 10µ C8 0.1µ C4 10µ C6 Vcc 10µ 15 14 13 12 Lch IN Lch OUT GND GND CXA1842S Rch IN Rch OUT 10 9 10µ 8 C13 10µ C7 0.022µ 7 SW2 6 SW1 5 SW4 4 C5 SW3 3 0.1µ C1 2 C3 1 11 C14 10µ 10µ Application circuits shown are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits or for any infringement of third party patent and other right due to same. Mode Switch Correspondence No. 1 2 3 4 5 MODE Simulated Stereo Surround A Surround B Pass Vocal cancel SW1 ON ON OFF OFF — SW2 ON OFF ON OFF — SW3 ON ON ON ON OFF —...don't care Bass boosting ON when SW4=ON (Invalid during vocal cancellation) VTH for SW ... VTH (H) = VCC to 3 V, VTH (L) = 2 V to GND —5— CXA1842S Description of Functions (1) Simulated Stereo The sum of the L and R signals is input to the Simulated Stereo* (hereafter S.S) block, and a simulated stereo signal is generated. (2) Surround A (matrix surround) The difference of the L and R signals is raised in level by the VCA (maximum 18 dB (typ.)), and is added to the raw signal. (3) Surround B The difference of the L and R signals is raised in level by the VCA (maximum 18 dB (typ.)), is input to the S.S block, and is then added to the raw signal. (4) Pass The L and R signals are output without modification. (5) Vocal Cancellation The difference of the L and R signals is input to the S.S block after first passing through the AGC circuit, and is then output to L and R. In contrast with conventional products, the vocal cancel signal (L-R signal) is raised in level by the VCA (max. 12 dB typ.), and low frequency part is enhanced, to prevent reduction in the acoustic pressure level when vocal cancellation is ON. * Simulated Stereo circuit: Phases in the audio band are divided into two separate orthogonal channels and treated as L+R and L-R signals, and are added and subtracted to produce simulated L and R signals. All-pass network. —6— CXA1842S Vocal cancellation Frequency response Surround Frequency response Sur B Lin Rout Vin=–40 dBm 20 Sur B Rin Rout Sste Rout +10 Vocal cancellation Surround (dB) +20 Sste Lout 0 –10 Vin=–10 dBm 0 –20 –20 100 1K –40 10K Frequency (Hz) 10 100 1K 10K Frequency (Hz) Bass boosting Frequency response Input/Output Characteristic 10 Surround f=50Hz 0 Output level (dBm) 20 Vin=–30 dBm 10 Vin=–20 dBm –10 Sur A f=1kHz –20 –30 –40 Sur A BB ON 0 –60 –50 –40 –30 –20 –10 Input level (dBm) 100 1K 10K Frequency (Hz) Supply voltage vs. Current consumption Current consumption (mA) 2 4 3 2 1 5 6 7 8 9 10 11 12 Supply voltage (VCC) —7— 0 10 1 THD (%) Bass boosting production (dB) Vin=–50 dBm CXA1842S Unit : mm + 0.1 0.05 0.25 – 22PIN SDIP (PLASTIC) + 0.4 19.2 – 0.1 7.62 + 0.3 6.4 – 0.1 12 22 0° to 15° 11 1 0.5 ± 0.1 + 0.15 0.9 – 0.1 + 0.4 3.9 – 0.1 0.51 MIN 1.778 + 0.15 3.25 – 0.2 Package Outline PACKAGE STRUCTURE MOLDING COMPOUND EPOXY RESIN SONY CODE SDIP-22P-01 LEAD TREATMENT SOLDER PLATING EIAJ CODE SDIP022-P-0300 LEAD MATERIAL COPPER ALLOY PACKAGE WEIGHT 0.95g JEDEC CODE —8—