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

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

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

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

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

300pF

INL1 2

AMP1 AMP2

3INL2

INPUT L

600Ω

36dB

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

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

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

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

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

AUDIO MUSIC SENSOR

dB dB

V V

µ

µV µ µ

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

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