1
CXA2502M
E95621A5X-PS
Dolby
B-C Type Noise Reduction System for Playback
Description
The CXA2502M is a bipolar IC incorporating stereo
Dolby B-C type noise reduction (NR) system for
playback.
Pins of this IC are compatible with those of the
Dolby B type NR ICs CXA1102M/ CXA1552M.
A reduction in the number of external parts and
small package have been achieved due to the fact
that the spectral skewing circuits are all on-chip and
this IC is intended for playback.
Features
Few external parts
Spectral skewing circuit are on-chip
NR OFF/B/C and AUX/TAPE switches
Small package (16-pin SOP)
Low current consumption 12mA Typ.
Built-in two channels
Structure
Bipolar silicon monolithic IC
Absolute Maximum Ratings (Ta = 25C)
Supply voltage
V
CC
17
V
Operating temperature
Topr
40 to +85
C
Storage temperature
Tstg
65 to +150
C
Allowable power dissipation
P
D
600 (SOP) mW
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.
16 pin SOP (Plastic)
This IC is available only to the licensees of Dolby Laboratories Licensing Corporation from whom licensing and applications
information may be obtained.
"Dolby" and the double D symbols are trademarks of Dolby Laboratories Licensing Corporation.
2
CXA2502M
Block Diagram, Pin Configuration and Application Circuit
HDET
HLS
HLS
HDET
LDET
LLS
LLS
LDET
SSK
SSK
IREF
Mode
Control
MOA
MOA
P12
P11
PBIN1
(30dBm)
AUXIN1
(30dBm)
P13
LINEOUT1
(6dBm)
P1
P23
LINEOUT2
(6dBm)
V
CC
C2
10
V
CC
C21
1
AUXIN2
C22
1
PBIN2
C1
47
VCT
NRSW
C
B
OFF
C23
1
LINEOUT2
TCH2
C24
100n
TCL2
C25
68n
2
3
4
5
6
7
8
1
P21
P22
AUXIN2
(30dBm)
PBIN2
(30dBm)
C11
1
AUXIN1
TAPE
AUX
C12
1
PBIN1
GND
IREF
MODE
C13
1
LINEOUT1
TCH1
C14
100n
TCL1
C15
68n
R1
20k
9
10
11
12
13
14
15
16
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.
3
CXA2502M
Pin Description
Pin
No.
Symbol
Z (in)
VDC (V)
Equivalent circuit
Description
3
14
PB IN
40K
VCT
Playback input.
Reference level
= 30dBm
V
CC
GND
VCT
40k
1
16
AUX IN
40K
VCT
Auxiliary input.
Reference level
= 30dBm
V
CC
GND
VCT
40k
6
11
LINE OUT
0
VCT
Line output.
200
V
CC
200
GND
2
V
CC
V
CC
Positive power supply.
4
VCT
0
VCT
Dual power supply:
Ground
Single power supply:
Vcc/2
5
NRSW
--
--
NR control
High:
C type
Medium:B type
Low:
NR OFF
V
CC
GND
22k
50A
4
CXA2502M
7
10
TCH
--
0.4V
Time constant for the
HLS.
V
CC
GND
36k
13k
330k
8
9
TCL
--
0.4V
Time constant for the
LLS.
V
CC
GND
13.5k
480k
15
GND
GND
Dual power supply:
Negative power supply
Single power supply:
Ground
12
MODE
--
--
MODE control
High: TAPE
Low: AUX
V
CC
GND
22k
50A
13
IREF
0
1.25V
Reference current
which determines the
built-in filter cut-off
frequency.
V
CC
GND
1.25V
Pin
No.
Symbol
Z (in)
VDC (V)
Equivalent circuit
Description
5
CXA2502M
Electrical characteristics
(Ta = 25C, V
CC
= 9V)
Characteristics
Symbol
Min.
P/A
NR
f (Hz)
Other conditions
Typ.
Max.
Unit
Operating voltage
Vopr
I
CC
Vlout
Vlin
Vpin
B-R-1
B-R-2
B-R-3
B-R-4
C-R-1
C-R-2
C-R-3
C-R-4
C-R-5
C-R-6
AUX
PB
PB
PB
PB
PB
PB
PB
PB
PB
PB
PB
OFF
OFF
OFF
B
B
B
B
C
C
C
C
C
C
1k
1k
1k
500
5k
10k
10k
500
500
2k
2k
5k
10k
No Signal
25dB
25dB
40dB
0dB
60dB
25dB
60dB
25dB
25dB
0dB
7.2
8.0
7.0
32
32
1.4
3.9
9.7
1.1
14.2
7.2
18.7
5.4
3.5
5.5
--
12.0
6.0
30
30
2.9
5.4
10.4
0.4
16.2
9.2
20.7
7.4
5.5
3.5
16.0
18.0
5.0
28
28
4.4
6.9
11.4
1.9
18.2
11.2
22.7
9.4
7.5
1.5
V
mA
dBm
dBm
dBm
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
Current consumption
LINEOUT level
AUX IN level
PB IN level
Decode characteristics
B type boost
(1)
(2)
(3)
(4)
C type boost
(1)
(2)
(3)
(4)
(5)
(6)
Measurement conditions
Signal handling
Vomax
PB
OFF
1k
THD = 1%
13.5
16.0
--
dB
1) NR OFF
THD (OFF)
PB
OFF
1k
+10dB
--
0.01
0.1
%
2) B
THD (B)
PB
B
1k
+10dB
--
0.03
0.1
%
3) C
THD (C)
PB
C
1k
+10dB
--
0.04
0.2
%
REC-PB
PB-REC
ch to ch
CT-1
CT-2
CT-3
PB
AUX
PB
OFF
OFF
OFF
1k
1k
1k
0dB
0dB
0dB
--
--
--
85
85
68
70
70
60
dB
dB
dB
Offset voltage
(OFF-C type)
Voff
PB
OFF
C
--
100
0
100
mV
Decode
S/N ratio
SN (CCIR)
PB
C
--
Rg = 5k
(CCIR/ARM)
75
83
--
dB
Total harmonic distortion
0dB means the level which provides 6dBm to the line output when NR is off.
6
CXA2502M
Electrical Characteristics Measurement Circuit
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
1
Audio
SG
DC Volt
Meter
S12
S11
C11
1
C12
1
C14
100n
C15
68n
VMODE
C13
1
S2_1
CCIR/ARM
Filter
S21
C21
1
S22
C1
100
C22
1
C24
100n
VNRSW
C23
1
S2_2
Audio
Analyzer
A
V
CC
S3
AUXIN1
GND
PBIN1
IREF
MODE
LINEOUT1
TCH1
TCL1
AUXIN2
V
CC
PBIN2
VCT
NRSW
LINEOUT2
TCH2
TCL2
CXA2502M
C25
68n
C2
100
R1
20K
7
CXA2502M
Application Note
The CXA2502M is a stereo Dolby B-C type NR IC like the CXA1560 series.
Few external parts and smaller package can be achieved because this IC has a built-in spectral skewing circuit
and the reduced number of pins for playback.
1) Power Supply
The CXA2502M is designed to operate on either single or dual power supply.
For dual power supply, connect VCT pin to GND, and GND pin to the negative power supply.
For single power supply, connect GND pin to GND. V
CC
/2, generated from the internal circuit, is output to
VCT pin.
Connect a by-pass capacitor between this pin and GND.
The operating voltage range is 7.0 to 16V, which satisfies the signal handling of 12dB specified by the Dolby
Laboratories.
2) Operation Mode Control
The CXA2502M has built-in electronic switches. The operations are controlled by the DC voltages of NRSW
and MODE control pins. Table 1 shows the switching truth tables.
For single power supply, VH, VM and VL correspond to V
CC
, V
CC
/2 and GND, respectivery.
For dual power supply, VH, VM and VL correspond to V
CC
, GND and V
EE
, respectively.
Refer to "threshold" on the characteristics graph for the thresholds of the control voltages. NRSW and MODE
control pins are connected to VCT via a 50k
resistor, so when the pin is open, VM condition results.
Table 1
3) Reference level
The CXA2502M Dolby level is 6dBm (388mVrms). The reference level of the playback input pin (PB IN) is
defined as the levels which provide the line output level to the line output pin (LINE OUT) in NR OFF mode.
NRSW
C type
B type
NR OFF
VH
VM
VL
MODE
TAPE
AUX
8
CXA2502M
Example of Representative Characteristics
Quiescent current consumption vs. Supply voltage
V
CC
Supply voltage [V]
4
6
8
10
12
14
16
I
CC
Quiescent current consumption [mA]
9
10
11
12
13
14
15
Decode Mode
NR OFF
B type
C type
Quiescent current consumption vs. Input level
Input level [dB]
12
0
4
8
12
I
CC
Quiescent current consumption [mA]
9
10
11
12
13
14
15
Decode Mode
V
CC
= 9V
0dB = 6dBm
8
4
NR OFF
B f = 10kHz
C f = 10kHz
B f = 1kHz
C f = 1kHz
Signal handling
V
CC
Supply voltage [V]
4
6
8
10
12
14
16
Signal handling [dB]
0
10
20
Decode Mode
f = 1kHz
THD = 1%
0dB = 6dBm
NR OFF
C type
Load characteristics
Frequency [Hz]
100
300
1k
0
6
10
Decode Mode
V
CC
= 9V
THD = 1%
f = 1kHz
NR OFF
Maximum output level [dBm]
2
8
12
4
3k
10k
12
10
8
6
4
2
0
B type decode characteristics
500
200
100
1k
2k
5k
10k
20k
Frequency [Hz]
Decode boost [dB]
V
CC
= 9V
0dB = Lineout Level
0dB
40dB
30dB
20dB
10dB
2
24
20
16
12
8
4
0
C type decode characteristics
500
200
100
1k
2k
5k
10k
20k
Frequency [Hz]
Decode boost [dB]
V
CC
= 9V
0dB = Lineout Level
50dB
60dB
40dB
30dB
20dB
10dB
0dB
4
9
CXA2502M
NR OFF total harmonic distortion-1
Output level [dB]
4
0
4
8
12
16
20
Distortion [%]
0.001
0.01
0.1
Decode Mode
V
CC
= 9V
0dB = 6dBm
f = 10kHz
f = 100Hz
f = 1kHz
B type total harmonic distortion-1
Output level [dB]
4
0
4
8
12
16
20
Distortion [%]
0.001
0.01
0.1
Decode Mode
V
CC
= 9V
0dB = 6dBm
f = 10kHz
f = 100Hz
f = 1kHz
C type total harmonic distortion-1
Output level [dB]
4
0
4
8
12
16
20
Distortion [%]
0.01
0.1
1.0
Decode Mode
V
CC
= 9V
0dB = 6dBm
f = 10kHz
f = 100Hz
f = 1kHz
NR OFF total harmonic distortion-2
Output level [dB]
4
0
4
8
12
16
20
Distortion [%]
0.001
0.01
0.1
Decode Mode
f = 1kHz
0dB = 6dBm
V
CC
= 7V
V
CC
= 16V
B type total harmonic distortion-2
Output level [dB]
4
0
4
8
12
16
20
Distortion [%]
0.001
0.01
0.1
Decode Mode
f = 1kHz
0dB = 6dBm
V
CC
= 7V
V
CC
= 16V
C type total harmonic distortion-2
Output level [dB]
4
0
4
8
12
16
20
Distortion [%]
0.01
0.1
1.0
Decode Mode
f = 1kHz
0dB = 6dBm
V
CC
= 7V
V
CC
= 16V
10
CXA2502M
Cross talk
Frequency [Hz]
100
300
1k
V
CC
= 9V
Input = +10dB
Refer to Dolby Level
NR OFF
Cross talk [dB]
30
3k
10k
40
50
60
70
80
90
CH to CH
AUX to PB, PB to AUX
MODE control threshold
V
CC
Power supply [V]
4
6
8
10
12
14
16
V
CM
MODE control voltage [V]
2
4
6
8
10
12
14
PB
AUX
0
NR control threshold
V
CC
Supply voltage [V]
4
6
8
10
12
14
16
V
CN
NR control voltage [V]
2
4
6
8
10
12
14
C type
NR OFF
0
B type
V
CC
VCT
11
CXA2502M
Package Outline
Unit: mm
PACKAGE STRUCTURE
PACKAGE MATERIAL
LEAD TREATMENT
LEAD MATERIAL
PACKAGE MASS
SONY CODE
EIAJ CODE
JEDEC CODE
SOP-16P-L01
SOP016-P-0300
COPPER ALLOY
SOLDER PLATING
EPOXY RESIN
16PIN SOP (PLASTIC)
9.9 0.1
+ 0.4
16
9
1
8
1.27
0.45 0.1
5.3 0.1
+ 0.3
7.9
0.4
6.9
1.85 0.15
+ 0.4
0.5
0.2
0.2 0.05
+ 0.1
0.1 0.05
+ 0.2
0.2g
0.15
M
0.24
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