SGS Thomson Microelectronics TDA7335 Datasheet



STEREO PREAMP + AMS + DOLBY B*

NOISE REDUCTIONPROCESSOR

DUAL CHANNEL PROCESSOR FOR PLAY­BACK APPLICATIONS.

STEREODOLBYB NR SYSTEM
LOW NOISE HEAD PREAMPLIFIER
MUTE, AUTOREVERSE, AMS (AUDIO MU-

SIC SENSOR)FUNCTIONS
INTERNALSWITCHES FOR EQUALIZATION
DOLBY REFERENCE LEVEL -6dBm

(388.2mV
MINIMUM NUMBER OF EXTERNALCOMPO-

NENTS
LOW SUPPLY CURRENT(18mA)
MIXED BIPOLAR/CMOSTECHNOLOGY

DESCRIPTION

The TDA7335 is a monolithic BICmos IC de­signed for use in stereo cassette player systems.

The device includes two separate audio channels
composed by low noise preamplifier, Dolby B
noise reduction system and Audio Music Sensor.

The dual preamplifier contains mute, autoreverse,
metal/normalfacilities for amplificationof low level
signal in applications requiring very low noise per­formances.

Each channel consists of two cascaded opera­tional amplifiers.

The first one, AMP1, has a fixed gain of 36dB,
low noise forward/reverse switchable input, and
allows magnetic heads connection directly to
ground. The secondone, AMP2, is a standard op­erational amplifier whose equalizing external
componentsfix the frequencyresponse.

The Audio Music Sensor circuit detects the inter­program space and then the starting point of mu­sical programs (the interprogram time and pro­gram detectiontime are externallyselectable).

The device contains Dolby B decoder NR chains
requiring very few external components and do
not require coils.

RMS)

ORDERING NUMBER: TDA7335

PIN CONNECTION

TDA7335

SDIP30

(Top view)

* Dolby B and the Double-D symbol are

trademarks of Dolby Laboratories Li­censing Corporation, San Francisco,
California94103-4813,USA.
This device is available only to Licens­ing and application information may be
obtainedfrom Dolby Lab.

November 1999

1/20

TDA7335

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Value Unit

V

S

tot Total Power Dissipation 1 W

P
T

op

T

stg

THERMAL DATA

Rth j-pins Thermal resistance junction-pins 85 °C/W

PIN FUNCTIONS

N. Name VDC (V) Function

1 GND Ground

2,3 IN L

4,27 EQLI, EQRI 4.6 Equalizer Inputs
5, 26 EQLO, EQRO 4.6 Equalizer Outputs
6, 25 OUTL, OUTR 4.6 Preamplifier Outputs
7, 24 DINL, DINR V

8 AMS SW 5.6 Audio Music Sensor Switch (ON/OFF) HIGH = ON

9 INTP Interprogram Time Constant (”Signal Detection”)
10 INTS Interspace Time Constant (”Blank Detection”)
11 MUTE Mute Switch ON = LOW (2)

12, 19 TLC, TCR 0.4 Dolby Time Constants
13, 18 DOUTL, DOUTR V

14 I
15 F/R SW 5.6 Forward/Reverse Switch HIGH = Forward LOW = Reverse
16 V
17 V
20 NR SW Noise reduction ON/OFF: HIGH = OFF (2)
21 AMS GIN 1.4 Audio Music Sensor Input Pin
22 AMS OUT Audio Music SensorOutput Pin (open collector configuration, see Fig. 2)
23 GND DIG. 0 Digital Ground

28, 29 IN R

30 EQ SW 0 Equalizer Switch (Low = normal position High = metal position)

(2) Internal pull-up resistor (digital high level if pin left open)

Supply Voltage 12 V

Operating Temperature Range -40 to 85
Storage Temperature Range -40 to 150

,INL

1

2

ref

S Positive Power Supply

ref

,INR

1

2

0 Preamplifier Left Inputs 1,2

Dolby NR Inputs

ref

Dolby Outputs

ref

1.2 Reference Current Source

VS/2 Reference Voltage

0 Preamplifier Right Inputs 1,2

C

°

C

°

2/20

Figure 1: ApplicationCircuit

C13

4.7µF

DOUTR

0.22µFC8

S

V

30K

OUTR

Vs

GND

R12

R10

R8

100K

10K

0.33µF C6(*)

0.68µF (*)

C11

18

TCR

19

AMSout

22

AMSGin

21 23

DINR

24

F/R SW

1.2K

0.68µF C19

NRSW

20

DOLBY

R13

100K

Vs

VREF

17

GND

4.7µF C14

AMS

V

16

S

S

V

BIAS

0.22µF

GND
1

C18

TDA7335

R11

43K 2%

IREF

14

11

MUTE

13

C10

DOUTL

DOLBY

12

TCL

0.68µF

INTS

10

INTP

9

DINL

OUTL

AMSSW

0.33µF C5(*)

EQ SW

8

7

1.2K

GND

Vs

Vs

30K

C16

100nF

C12

4.7µF

R9

100K

R14

C9 1µF

C7 0.1µF

470K R7

C15 10nF

GND

D94AU095B

OUTL

S

V

R15 30K

(*)

6.8K

1.2K

1K

R5

R2

TR2

1µF

C2

0.68µF C17

10nF C4

300K

R6

EQRI EQRO OUTR

15 25

RM RN

27 26

36dB

28INR2

INR1 29

AMP1 AMP2

AMP1 AMP2

36dB

3

INL2

INL1 2

INPUT R

INPUT L

RNRM

C3

10nF

R4

300K

4 5 30 6

EQLI EQLO

R3

R1

TR1

6.8K

1.2K

1K

1µF

C1

C20

0.68µF

(*) Capacitor tolerance is ±10%

3/20

TDA7335

Figure 1a: Components& Top Copper Layer of the Fig. 1 (1:1 scale).

Figure 1b:

Bottom Copper Layer of the Fig. 1 (1:1 scale).

4/20

TEST CIRCUIT

0.22µFC8

OUTR

S

V

R10

R8

4.7µF

100K

10K

C13

0.33µF C6(*)

0.68µF (*)

C11

DOUTR

18

TCR

19

AMSout

22

AMSGin

21 23

DINR

24

F/R SW

1.2K

S

V

NRSW

20

DOLBY

GND

VREF

17

4.7µF C14

AMS

V

16

S

S

V

BIAS

0.22µF

GND
1

C18

TDA7335

R11

43K

IREF

14

11

MUTE

13

C10

DOUTL

DOLBY

12

TCL

(*)

0.68µF

INTS

10

INTP

9

DINL

OUTL

AMSSW

0.33µF C5(*)

EQ SW

8

7

1.2K

C12

4.7µF

R9

100K

S

V

D94AU097A

C9 1µF

C7 0.1µF

470K R7

C15 10nF

OUTL

S

V

6.8K

1.8K

15 25

10nF C4

R5

300K

R2

C2

1µF

R6

EQRI EQRO OUTR

RM RN

27 26

36dB

28INR2

INPUT R

INR1 29

AMP1 AMP2

600Ω

600Ω

300pF

300pF

INL1 2

AMP1 AMP2

3INL2

INPUT L

600Ω

600Ω

36dB

300pF

300pF

RNRM

C3

10nF

R4

300K

4 5 30 6

EQLI EQLO

GND

R3

6.8K

R1

1.8K

C1

1µF

(*) Capacitor tolerance is ±10%

5/20

TDA7335

ELECTRICALCHARACTERISTICS (VS =8.5V;f=1KHz;Rg=600Ω;T

all level referenced to -6dBm/400Hz, at D

out with NR SW OFF; unle ss o t herwise sp ecif ied

=25°C; R11 =43kΩ;

amb

see a pplicat ion circuit of Fig. 1) NAB METAL po sition .

SUPPLY

Symbol Parameter Test Condition Min. Typ. Max. Unit

V

S

I

S

V

ref

DC DC Voltage pin 14 (R11 = 43K) 1.15 1.25 1.35 V

V

SVR Ripple Rejection

MUTE

I

MUTE

MUTE

Supply Voltage 8 8.5 10.5 V
Supply Current 11 18 26 mA
Reference Voltage (pin 17) 4 4.3 4.6 V

(Input referred)
Mute Threshold Pin11 ON

th

V

ripple

f

=1KHz DolbyON

ripple

OFF

80
85

0

2.0

90
95

=0.3Vrms DolbyOFF

Mute Current 10 20
Mute Attenuation 55 65 dB

A

0.8
V

S

PREAMPLIFIER

Symbol Parameter Test Condition Min. Typ. Max. Unit

R

I

I

V Closed Loop Gain pin 4, 5 and 26, 27 shorted 32.5 35.5 38.5 dB

G

G

∆

R

M

R

∆

N Resistance Normal Position 50 160 300 Ω

R

N Total Input Noise Unw.B=20Hzto20KHz;Rg =0Ω

e

R

O Output Impedance (pin 6, 25) 0.9 1.2 1.7 KΩ

F/R

F/R

EQ

EQ

Input Resistance (pin 2, 3, 28, 29) 30 50 70 K

I

Input Bias Current 10

Closed Loop Gain Match -1 1 dB

V

Resistance Metal Position 4.35 5.8 7.25 K
Metal Resistance Matching -2 0 2 dB

M

0.45

R

A weighted; R

l Reverse Low Level(pin 15) IN2 = ON; IN1 = OFF 0 0.8 V

Forward High Level (pin15) IN2= OFF; IN1=ON 2 V

h

NormalLowLevel (pin30) 0 1.5 V

l

MetalHigh Level (pin30) 3.5 V

h

g

=600

g

Ω

=600

Ω

0.8

0.5

S

S

AUDIO MUSIC SENSOR

dB
dB

V
V

µ

µ

µV
µ
µ

V

V

A

Ω

A

Ω

V
V

Symbol Parameter Test Condition Min. Typ. Max. Unit

OUT AMS Output Current 5 mA

IAMS

OUT AMS Output Low Level IAMOUT = 2mA 200 800 mV

VAMS

21 Input Impedance 0.8 1.1 1.4 K

R

P

AMS

AMS

TH1 Interprogram Threshold Voltage (pin9) 1.2 1.45 1.7 V

V

VTH

AMS

IAMS

AMS OFF Low Level 0 0.8 V

swl

AMS ON High Level 2 V

swh

Interspace Threshold Voltage (pin 10) 4 4.3 4.6 V

2

AMS Threshold Level see note (3) 0.6 1 1.4 V

th

AMS Switch pin Current 5 10 15

sw

S

DOLBY SECTION

Symbol Parameter Test Condition DOLBY Min. Typ. Max. Unit

Voltage Gain f = 1KHz; OFF -1 0 1 dB

V Gain Matching OFF -0.5 0.5 dB

Dolby Input Res. (pin 7, 24) 46 63 K

I

6/20

G

∆G

RD

V

Ω

V

A

µ

Ω