ST TDA7256 User Manual



30W BRIDGECAR RADIO AMPLIFIER

NO AUDIBLE POP DURING MUTE AND
STANDBYOPERATIONS

MUTINGTTL COMPATIBLE
VERYLOW STANDBY CONSUMPTION
PROGRAMMABLETURN ON DELAY
DIFFERENTIAL INPUT
SHORTCIRCUITPROTECTIONS:

RL SHORT - OUT TO GROUND - OUT TO V
OTHERPROTECTIONS:

- Load dump voltage surge

- LoudspeakerDC current

- Very inductive load

- Overratingtemperature

- Openground

DESCRIPTION

The TDA7256 is a class AB fullyprotected bridge
power amplifier, designed for car radio applica-

S

TDA7256

MULTIWATT11

ORDERING NUMBER: TDA7256

tions. The high current capability allows to drive
low impedance loads (up to 2Ω). The differential
inputs availability makes it particularlysuitable for
boostersand active loudspeakersapplications.

BLOCK DIAGRAM

October 1998

This is advanced information on a new product now in development or undergoing evaluation. Detailsare subject to change without notice.

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TDA7256

PIN CONNECTION (Top view)

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Test Conditions Unit

Operating Supply Voltage 18 V

S

DC Supply Voltage 28 V

S

Peak Supply Voltage (for 50ms) 40 V

S

Output Peak Current (non repetiitive t = 0.1ms) internally limited
Output Peak Current Repetitive f > 10Hz 5.5 A
Power Dissipation (Tcase = 85°C) 36 W
Storage and Junction Temperature Range -40 to +150 °C

P

T

stg,TJ

V
V
V

I

o

I

o
tot

THERMAL DATA

Symbol Description Value Unit

R

th j-case

Thermal Resistance Junction-case Max 1.8 °C/W

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TDA7256

ELECTRICAL CHARACTERISTICS

= 14.4V, RL=4Ω, f = 1KHz; T

(V

S

=25°C, unless otherwise

amb

specified)

Symbol Parameter Test Condition Min. Typ. Max. Unit

V

S

I

q

R

CMR Common Mode Rejection f = 1KHz, V

V

OS

P

o

d Distortion P

G

V

e

N

SVR Supply Voltage Rejection R

T

SD

Supply Voltage 8 18 V
Quiescent Drain Current 80 150 mA
Input Resistance 50 K

i

= 100mV 60 dB

in

Output Offset Voltage 150 mV
Output Power d = 10%

R

=4Ω

L

R

= 3.2Ω

L

R

=2

Ω

L

= 0.1W to 13W 0.05 0.5 %

o

18 22

26
30

Voltage Gain (CL) 36 dB
Total Input Noise Voltage Rg= 10KΩ, B = 22Hz to 22KHz 3 10 µV

= 10KΩ,Vr= 1Vrms,

g

45 60 dB

f = 300Hz

Muting Attenuation V

= 1Vrms,

ref

60 dB

f = 100Hz to 10KHz
Muting-in Threshold Voltage Pin 1 2.4 V
Muting-out Threshold Voltage Pin 1 0.8 V
Stand-by Attenuation Vref = 1Vrms 60 dB
Stand-by Current Consumption 100
Thermal Shut-down Junction

145 °C

Temperature

Ω

W
W
W

A

µ

Figure 1:

Testand Application Circuit

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