Document
CXA2020M/S
EIAJ Sound Multiplexing Decoder
Description The CXA2020M/S, is a bipolar IC designed as EIAJ TV sound multiplexing decoder, provides various functions including sound multiplexing demodulation, broadcast mode identification (stereo/bilingual discrimination display), mode display, and muting. Features • Adjustment free of filter. • High frequency stereo separation improved. • An internal active filter greatly reduces the external parts. • Use of the countdown method for broadcast mode identification eliminates the necessity of adjusting the identification system (Cue oscillator). • Output level: 520mVrms (1kHz, monaural, 100%). • Internal filter eliminates interference from digital facsimile signals. • The discrimination time needed to shift from multiplexing sound to monaural sound is reduced. • Forced monaural mode can be set to operate only for stereo broadcasts or for stereo/bilingual broadcasts. Applications • Color TVs • Hi-Fi VCRs Structure Bipolar silicon monolithic IC Pin Configuration
GND 1 NC 2 REFL 3 Vcc 4 NC 5
CXA2020M 28 pin SOP (Plastic)
CXA2020S 22 pin SDIP (Plastic)
Absolute Maximum Ratings (Ta = 25°C) [ ( ) is the pin No. for the CXA2020S.] • Supply voltage VCC 10 • Input signal (Pin 6) Vis 0.6 • Control voltage (Pins 5, 12, 13, 14) Vic VCC • Operating temperature Topr –20 to +75 • Storage temperature Tstg –65 to +150 • Allowable power dissipation PD (A2020M) 1000 (A2020S) 900 • LED drive current ILED 10 Operating Supply Voltage Range 8.5 to 9.5
V Vp-p V °C °C mW mW mA V
CXA2020M
28 SUBI 27 NC 26 SC OUT 25 SC IN 24 NC GND 1 NC 2 REFL 3 Vcc 4
CXA2020S
22 SUBI 21 SC OUT 20 SC IN 19 MC OUT
CXA2020M
MPX IN 7 NC 8 CUBI 9
22 MC IN 21 L OUT 20 R OUT 19 M OUT 18 FOMO 17 MUTE 16 MODE 15 NC
MPX IN 6 NC CUBI 7 8
CXA2020S
MO MODE 6
23 MC OUT
MO MODE 5
18 MC IN 17 L OUT 16 R OUT 15 M OUT 14 FOMO 13 MUTE 12 MODE
NC 10 LEDST 11 LEDSU 12 LEDM 13 NC 14
LEDST 9 LEDSU 10 LEDM 11
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–
E94Y28-ST
CXA2020M/S
Block Diagram CXA2020M
MC OUT SC OUT M OUT R OUT L OUT FOMO MODE MC IN SUBI SC IN MUTE NC NC NC
15 14 12 LED DRIVE 11
28
27
26
25
24
23
22
21
20
19
18
17
16
TEST
SUBDEEM
MAINDEEM MAIN SUB
OUTPUT AMP & OUTPUT SW L R
MAIN OUT
FM DEMOD
MATRIX IIL LOGIC & CONT CUE CARRIER 3.5fH 952Hz CLOCK CLOCK 3.5fH VCO 952Hz BPF LED DRIVE
SUB DET SUB BPF 4.5fH TRAP CUE BPF
BUFFER BIAS CURRENT BIAS VOLTAGE VOLTAGE REGULATOR
AM DEMOD
COMP
IN AMP
IBIAS
1
2
3
4
5
6
7
MPX SIGNAL 9 8
10
11
12
13
MO MODE
LEDST
CUBI
NC
GND
REFL
MPX IN
NC
NC
LEDSUB
NC
CXA2020S
MC OUT SC OUT M OUT R OUT FOMO L OUT MODE LEDMAIN SUBI SC IN MC IN MUTE
22
21
20
19
18 TEST
17
16
15
14
13
SUBDEEM
MAINDEEM
OUTPUT AMP & OUTPUT SW MAIN L R SUB
MAIN OUT
FM DEMOD
MATRIX IIL LOGIC & CONT CUE CARRIER 3.5fH 952Hz CLOCK CLOCK 3.5fH VCO 952Hz BPF
SUB DET SUB BPF 4.5fH TRAP CUE BPF
BUFFER BIAS CURRENT BIAS VOLTAGE VOLTAGE REGULATOR
AM DEMOD
COMP
IN AMP
IBIAS
1
2
3
4
5
6
MPX SIGNAL 7
8
9
10
MO MODE
MPX IN
CUBI
NC
LEDST
NC
–2–
LEDSUB
REFL
GND
Vcc
LEDMAIN
Vcc
NC
CXA2020M/S
Pin Description (Ta = 25°C, VCC = 9V) PIn No. SOP SDIP 1 2 5 8 10 14 15 24 27 1 Symbol GND Pin voltage 0
The pin numbers in parentheses are for the CXA2020S. Equivalent circuit GND. Description
2 7
NC
—
—
Keep these pins open. (They are not connected to the chip.)
Vcc
147
3
3
REFL
1.2V
3 3.3k 20k 24k 20k GND
The noise elimination filter connection of internal reference voltage.
4
4
VCC
—
Power supply. Forced monaural mode selection. When Low or open, the forced monaural mode operates for stereo broadcasts only; if High, the forced monaural mode operates for both stereo and bilingual broadcasts.
6 (5) 70k
6
5
MO MODE
—
50k 10.5k GND
Vcc 138k 147
7
6
MPXIN
4.1V
7 (6) 25k 80µ 30k 4.2V GND
Sound multiplexing signal input. Typical input level = 70mVrms (monaural, 100%)
Vcc
1k 147 40k 40k
Vcc
9
8
CUBI
4.1V
11k 2k 4.2V
9 (8) 40k
Bias capacitor connection of Cue pulse generator.
–3–
CXA2020M/S
Pin No. SOP SDIP
Symbol
Pin voltage
11 (9) 12 (10) 13 (11)
Equivalent circuit
Description
11
9
LEDST
10.5k 10.5k 64k 10.5k 64k 64k 16k 16k
12
10
LEDSU
—
Mode indicator LED connection. Pin 11 (9): stereo Pin 12 (10): sub Pin 13 (11): main
13
11
LEDM
16k GND
Vcc 20µ
16
12
MODE
—
20k 16 (12) 10.5k
16k 4.2V 40k GND
DC voltage-based output mode switch for bilingual broadcasts.
17 (13) 70k
17
13
MUTE
—
50k 10.5k GND GND
Output muting. When High, only DC is output from Pins 19, 20 and 21 (15, 16 and 17).
18 (14) 70k
18
14
FOMO
—
50k 10.5k GND .