--1--

E92315A79-TE

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.

Absolute Maximum Ratings (Ta=25 °C)

· Supply voltage

· Operating temperature

Topr

40 to +85

°C

· Storage temperature

Tstg

65 to +150

°C

· Allowable power dissipation

SOP16 (A1551M/A1552M/A1553M)

500 mW

DIP16 (A1550P/A1551P/A1552P/A1553P) 900 mW

These ICs are 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 trade marks

of Dolby Laboratories Licensing Corporation.

Description

The CXA1550/CXA1551/CXA1552/CXA1553 are

bipolar ICs providing two separate Dolby B type

noise reduction processors. The series is

composed of seven devices having four Dolby levels

and two types of package for various applications.

These devices feature very few external

components, which is achieved by monolithic filter

circuits using integrated thin film capacitors with high

capacitance.

Features

· Pin replaceable with CXA1100 series

· Minimum number of external components

· NR ON/OFF/Double Speed, REC/PB switches

included

· Small package (16 pin SOP, 16 pin DIP)

· Low current consumption 5.6mA typ.

· Dual channel processors in one chip

· Double speed encode and decode functions are

provided.

Dolby B

type Noise Reduction System

CXA1551M/CXA1552M

CXA1550P/CXA1551P

CXA1553M

CXA1552P/CXA1553P

16 pin SOP (Plastic)

16 pin DIP (Plastic)

CXA1550P, CXA1551M/P

CXA1552M/P, CXA1553M/P

--2--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

Block Diagram

I
N

/
P

I
N

.
2

.
1

.
2

I
N

/
O

I
N

.
1

.
2

LIN

T 1

LIN

T 2

:

A

t
t
e

t
o

:

S

i
d

i
n

:

D

t
e

t
o

--3--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

Pin Description and Equivalent Circuit

(Ta=25 °C, V

=12 V, single supply, no signal)

Symbol

Z (in)

VDC

Equivalent circuit

Description

No.

(V)

1, 16

3, 14

6, 11

REC IN

PB IN

VCT

NRSW

LINE OUT

40 k

2 k

6.0 V

12.0 V

6.0 V

GND

40k

GND

40k

GND

50k

GND

200

Recording (encode) input pin

power supply pin

Playback (decode) input pin

/2 output pin

NR control pin

H : Double speed

M : NR off

L : NR on

Line (decode) output pin

--5--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

Electrical Characteristics

Ta=25 °C, Dolby Level: 10 dBm (=245 mVrms) at RECOUT, 0 dBm=775 mVrms, V

=15 V (CXA1550),

=12 V (CXA1551), V

=9 V (CXA1552), V

=6 V (CXA1553) unless otherwise specified

Characteristics

CXA1550

Operating

CXA1551

voltage

CXA1552

CXA1553

CXA1550

Current

CXA1551

consumption

CXA1552

CXA1553

CXA1550

LINE OUT

CXA1551

level

CXA1552

CXA1553

REC IN Level

PB IN Level

(1)

Encode

(2)

characteristics

(3)

(Boost)

(4)

(5)

CXA1550

Signal

CXA1551

handling

CXA1552

CXA1553

CXA1550

CXA1551

Total

CXA1552

harmonic

CXA1553

distortion

CXA1550

CXA1551

CXA1552

CXA1553

Encode S/N ratio

REC-PB

Crosstalk

PB-REC

REC ch to ch

PB ch to ch

REC OUT offset voltage

(NR ON-OFF)

REC

Control

voltage

OFF

Symbol

Vopr

Vlout

Vrin

Vpin

B-R-1

B-R-2

B-R-3

B-R-4

B-R-5

Vomax

THD

(OFF)

THD

(ON)

(CCIR)

CT-1

CT-2

CT-3

CT-4

Voff

VC-R

VC-P

VC-ON

VC-OFF

VC-

Test Conditions

R/P

REC

OFF

f (Hz)

1 k

500

2 k

5 k

10 k

1 k

other

Signal

handling

12 dB

No signal

25 dB

40 dB

0 dB

THD=1 %

Rg=5 k

(CCIR/ARM)

Min.

Typ.

Max.

Unit

11.5

16.0

8.5

16.0

6.5

16.0

5.0

16.0

3.5

5.6

7.7

3.5

5.5

7.7

3.5

5.3

7.7

3.5

5.1

7.7

1.0

0.0

1.0

dBm

4.0

3.0

2.0

dBm

7.0

6.0

5.0

dBm

11.0

10.0

9.0

dBm

1.4

2.9

4.4

5.5

7.0

8.5

3.9

5.4

6.9

9.7

10.4

11.9

1.1

0.4

1.9

13.5

15.3

14.0

15.9

14.0

15.9

13.0

15.0

0.03

0.2

0.04

0.2

0.05

0.2

0.06

0.2

0.03

0.3

0.04

0.3

0.06

0.3

0.09

0.3

0.5

2.5

0.5

2.5

(2) NR ON

(1) NR OFF

0 dB means the level which provides the Dolby level at the recording output in the noise reduction off mode.

--6--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

Test Circuit

.
5

.
1

.
7

.
1

.
7

.
5

.
1

.
5

.
1

.
7

.
1

.
7

.
2

t
e

I
R

/
A

i
l
t
e

i
s

t
o

r
t
i
o

l
y

i
o

N 2

LIN

T 2

T 1

N 1

LIN

T 1

--7--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

Switchable Processor with Single Supply

Note) 1. Resistor and capacitor tolerances are ±10 % and ±20 % respectively unless otherwise specified.

2. When resistors RT are connected to Pin 4 for the MPX filter termination, increase the capacitances

of C

and C

) to 470 µF and 4.7 µF respectively.

Switching Processor with Split Power Supply

Note) Resistor and capacitor tolerances are ±10 % and ±20 % respectively unless otherwise specified.

C14
2.2

C3
10

C12/1

C11
1

R2
10k

C15
2.2

C25
2.2

C24
2.2

C13 (10%)
0.1

R1
(2%)
18k

LINE OUT

REC/PB

REC
PB

REC OUT
(10dBm)

C21/1

C22/1

PB IN

(30dBm)

REC IN

(30dBm)

PB IN

(30dBm)

REC IN

(30dBm)

C2
100

C1
22

NR SW

2 OFF ON

C23 (10%)
0.1

C14
2.2

C15
2.2

C24
2.2

C25
2.2

C13 (10%)
0.1

LINE OUT

REC/PB

REC

REC OUT
(10dBm)

C12
1

C11
1

PB IN

(30dBm)

PB IN

(30dBm)

REC IN

(30dBm)

REC IN

(30dBm)

C1
100

C2
100

C21
1

C22
1

C3
100

C23 (10%)
0.1

R2
10k

R1
(2%)
18k

NR SW

OFF

--8--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

Playback Processor with AUX input

Note) 1. Resistor and capacitor tolerances are ±10 % and ±20 % respectively unless otherwise specified.

2. When the AUX input is unnecessary, remove R

, C

and TAPE/AUX control switch and

connect Pin 12 to V

C14
2.2

C12
1

C11
1

R2
10k

C24
2.2

C13 (10%)
0.1

R1
(2%)
18k

LINE OUT

TAPE/AUX

AUX
TAPE

C21
1

C22
1

TAPE IN

(30dBm)

TAPE IN

(30dBm)

AUX IN

(30dBm)

AUX IN

(30dBm)

C2
100

C1
22

NR SW

2 OFF ON

C13 (10%)
0.1

C3
10

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.

--9--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

Notes on Applications

1) Power supply

The CXA1550 series is designed to operate on either single or split power supply. The ripple rejection

performance is excellent for either supply. VCT (Pin 4) is a reference voltage of the V

/2 buffer amplifier.

With single power supply operation, internally generated V

/2 voltage appears at the pin, and a bypass

capacitor has to be connected between the pin and ground. On split power supply operation, the VCT (Pin

4) pin has to be connected to ground, and V

(negative power supply) is supplied to the GND (Pin 15) pin.

2) Double speed (

The CXA1550 series provides double speed encode/decode modes, which offer high speed dubbing

function. On double speed mode, the frequency response shifts twice as the normal B type.

3) Operational mode control

The CXA1550 series provides fully electronic switching circuits. The functions are controlled by DC voltage

of the two control pins of REC/PB (Pin 12) and ON/OFF/

2 (Pin 5). The switching truth tables are shown in

Table 1.

Table 1.

Pin 12

Pin 5

Function

PB (Decode)

REC (Encode)

NR OFF

NR ON

Single Supply

2.5 V

0.5 V

0 V

0.5 V

2.5

2.5 V

0.5 V

0 V

Split Supply

+2.5 V

+0.5 V

0.5 V

2.5 V

+2.5 V

+0.5 V

It is desirable to provide CR time constant circuits at the mode control pins with time constant from 100

msec to 1 sec, which will reduce switching clicks effectively.

4) Reference levels

Characteristics and specifications of the Dolby noise reduction processor are defined as the levels and

measured with reference to the Dolby level. This particular level in these devices is 10 dBm (245 mVrms),

and is measured at the recording output (REC OUT) in the NR off mode.

The reference levels of the recording input (REC IN), playback input (PB IN) and line output (LINE OUT)

are defined as the levels which provide the Dolby level at the recording output in the NR off mode.

The CXA1550 series has a common silicon die, and has different internal connection (AL pattern). The

series provides four different line output levels for various applications. Other reference levels, recording

input level, playback input level and recording output level (=Dolby level) are identical in all devices.

The reference levels are as follows

Recording output level (=Dolby level)

10 dBm (245 mVrms)

Recording input level

30 dBm (24.5 mVrms)

Playback input level

30 dBm (24.5 mVrms)

Line output level

CXA1550

0 dBm (775 mVrms)

CXA1551

3 dBm (548 mVrms)

CXA1552

6 dBm (388 mVrms)

CXA1553

10 dBm (245 mVrms)

--10--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

5) MPX filter termination and C

for V

/2 (Pin 4)

The MPX (multiplex) filter termination method shown in Fig. 1 allows saving the coupling capacitors

between the buffer amplifiers and MPX filters. However, the channel to channel separation and REC to PB

crosstalk of low frequency signals will be degraded by the termination resistor RT. For example, 5 k

of R

will degrade the channel to channel separation to 50 dB. Better separation can be obtained by increasing

the capacitance of C

(Pin 4) to 220 µF or 470 µF.

The allowable minimum value of C

is 47 µF, and 100 µF is the standard recommended value. Larger

values of C

are generally desirable in order to improve the crosstalk and ripple rejection ratio.

6) Application for dubbing cassette decks

The CXA1550 series generates non decoded signal at the recoding output in the playback (decode) mode,

and can simplify the structure of dubbing decks. See the Sony' Dolby B/C type IC (CX20187/CXA1097Q or

CX20188/CXA1098Q) data sheet in detail.

Fig. 1

CXA1550 Series

C1
470

C21
4.7

C11
4.7

Line
Input

Buffer

MPX
Filter

--11--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

Example of Representative Characteristics

Quiescent current consumption vs. Supply voltage

i
e

t

c

r
r
e

t

c

t
i
o

(
m

)

Encode Mode

NR OFF

NR ON

Supply Voltage (V)

Current consumption vs. Input level (CXA1552)

r
r
e

t

c

t
i
o

(
m

)

Encode Mode
V

=9V

0dB=Dolby level

NR OFF

NR ON 1kHz
NR

2 1kHz

2 10kHz

Input level (dB)

NR ON encode characteristics

t

(
d

)

=9V

0dB=Dolby level

200

500

10k

20k

Frequency (Hz)

Double speed encode boost

Signal handling

i
g

l

h

l
i
n

(
d

)

Encode Mode
NR OFF
f=1kHz
THD=1%

A1553 A1552

A1551

A1550

10 12 14 16 18

20 22

Supply voltage (V)

Load characteristics (CXA1552)

i
m

t
p

t

l
e

l

(
d

)

200

500

10k

20k

Load resistance (

)

50dB

40dB

30dB

20dB

10dB

0dB

t

(
d

)

=9V

0dB=Dolby level

500

10k

20k

50k

Frequency (Hz)

50dB

40dB

30dB

20dB

10dB

0dB

Encode Mode
V

=9V

THD=1%
0dB=0.775Vrms

LINE OUT

REC OUT

NR ON 10kHz

--12--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

NR OFF total harmonic distortion 1 (CXA1551)

Double speed total harmonic distortion 1 (CXA1551)

Double speed total harmonic distortion 2 (CXA1550)

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

Encode Mode
V

=12V

0dB=Dolby level

f=10kHz

f=100Hz
f=1kHz

NR OFF total harmonic distortion 2 (CXA1550)

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

Encode Mode
V

=12V

0dB=Dolby level

f=10kHz

f=100Hz

f=1kHz

NR ON total harmonic distortion 2 (CXA1550)

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

NR ON total harmonic distortion 1 (CXA1551)

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

Encode Mode
V

=12V

0dB=Dolby level

f=10kHz

f=100Hz

f=1kHz

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

Encode Mode
0dB=Dolby level
f=1kHz

=15V

=11.5V

=15V

=11.5V

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

Encode Mode
0dB=Dolby level
f=1kHz

=15V

=11.5V

--13--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

NR OFF total harmonic distortion 3 (CXA1551)

Double speed total harmonic distortion 3 (CXA1551)

Double speed total harmonic distortion 4 (CXA1552)

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

Encode Mode
0dB=Dolby level
f=1kHz

NR OFF total harmonic distortion 4 (CXA1552)

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

NR ON total harmonic distortion 4 (CXA1552)

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

NR ON total harmonic distortion 3 (CXA1551)

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

Encode Mode
0dB=Dolby level
f=1kHz

=15V

=6.5V

=9V

=6.5V

=9V

=15V

=12V

=8.5V

=15V

=12V

=8.5V

=15V

=12V

=8.5V

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

Encode Mode
0dB=Dolby level
f=1kHz

=15V

Encode Mode
0dB=Dolby level
f=1kHz

=6.5V

=9V

--14--

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

Double speed total harmonic distortion 5 (CXA1553)

Crosstalk (CXA1552)

NR ON total harmonic distortion 5 (CXA1553)

NR OFF total harmonic distortion 5 (CXA1553)

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

t
a

l

h

r
m

i
c

i
s

t
o

r
t
i
o

(
%

)

Output level (dB)

1.0

0.5

0.2

0.1

0.05

0.02

0.01

Encode Mode
0dB=Dolby level
f=1kHz

=15V

=6V

=5V

=6V

=5V

=6V

=5V

=15V

r
o

t
a

l
k

(
d

)

500

10k

20k

Frequency (Hz)

100

=9V

NR OFF
Refer to Dolby Level

REC to PB
PB to REC
CH to CH

Encode Mode
0dB=Dolby level
f=1kHz

PACKAGE STRUCTURE

PACKAGE MATERIAL

LEAD TREATMENT

LEAD MATERIAL

PACKAGE MASS

EPOXY RESIN

SOLDER PLATING

COPPER ALLOY

19.2 0.1

+ 0.4

1 8

2.54

0.5 ± 0.1

1.2 ± 0.15

.
0

I
N

.
5

I
N

.
7

.
1

.
4

.
1

.
3

.
6

.
2

.
0

.
1

0° to 15°

16PIN DIP (PLASTIC)

1.0 g

SONY CODE

EIAJ CODE

JEDEC CODE

DIP-16P-01

DIP016-P-0300

Similar to MO-001-AE

1.All mat surface type.

Two kinds of package surface:

2.All mirror surface type.

SONY CODE

EIAJ CODE

JEDEC CODE

PACKAGE STRUCTURE

PACKAGE MATERIAL

LEAD TREATMENT

LEAD MATERIAL

PACKAGE WEIGHT

EPOXY RESIN

SOLDER PLATING

COPPER / 42 ALLOY

16PIN DIP (PLASTIC) 300mil

19.1 0.1

+ 0.4

2.54

.
4

.
1

.
3

.
2

.
0

.
1

.
6

0° to 15°

.
7

.
1

.
4

.
5

I
N

.
0

I
N

0.46 ± 0.1

1.53 ± 0.15

DIP-16P-03

DIP016-P-0300-B

Similar to MO-001-AE 1.0g

Package Outline Unit : mm

CXA1550P, CXA1551P

CXA1552P, CXA1553P

CXA1550P, CXA1551M/P, CXA1552M/P, CXA1553M/P

--16--

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: CXA1553

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: CXA1553