TA8276H

2002-02-13

TOSHIBA Bipolar Linear Integrated Circuit Silicon Monolithic

TA8276H

Max Power 35 W BTL × 4 ch Audio Power IC

The TA8276H is 4 ch BTL audio power amplifier for car audio

application.

This IC can generate more high power: P

OUT

MAX = 35 W as it

is included the pure complementary PNP and NPN transistor
output stage.

It is designed low distortion ratio for 4 ch BTL audio power

amplifier, built-in stand-by function, muting function, output
clipping detection and diagnosis circuit which can detect output
to V

/GND short and over voltage input mode.

Additionally, the AUX amplifier and various kind of protector

for car audio use are built-in.

Features

· High power : P

OUT

MAX (1) = 35 W (typ.)

= 14.4 V, f = 1 kHz, JEITA max, R

= 4 )

OUT

MAX (2) = 31 W (typ.)

= 13.7 V, f = 1 kHz, JEITA max, R

= 4 )

OUT

(1) = 23 W (typ.)

= 14.4 V, f = 1 kHz, THD = 10%, R

= 4 )

OUT

(2) = 20 W (typ.)

= 13.2 V, f = 1 kHz, THD = 10%, R

= 4 )

· Built-in output clipping detection and diagnosis circuit (pin 25)
· Low distortion ratio: THD = 0.02% (typ.)

= 13.2 V, f = 1 kHz, P

OUT

= 5 W, R

= 4 )

· Low noise: V

= 0.10 mVrms (typ.)

= 13.2 V, R

= 0 , G

= 26 dB, BW = 20 Hz~20 kHz)

· Built-in stand-by switch (pin 4)
· Built-in muting function (pin 22)
· Built-in AUX amplifier from single input to 2 channels output (pin 16)
· Built-in various protection circuit

: Thermal shut down, over voltage, out to GND, out to V

, out to out short, speaker burned

· Operating supply voltage: V

CC (opr)

= 9~18 V

Weight: 7.7 g (typ.)

TA8276H

2002-02-13

Figure 2 With pin 4 set to High,

Power is turned ON

OFF

10 k

to BIAS
CUTTING CIRCUIT

Power

Caution and Application Method

(Description is made only on the single channel.)

1. Voltage

Gain

Adjustment

This IC has no NF (negative feedback) terminals. Therefore, the voltage gain can't adjusted, but it makes

the device a space and total costs saver.

The voltage gain of Amp.1:

= 0 dB

The voltage gain of Amp.2A, B:

= 20 dB

The voltage gain of BLT Connection: G

V (BTL)

= 6 dB

Therefore, the total voltage gain is decided by expression below.

= G

+ G

V (BTL)

= 0 + 20 + 6 = 26 dB

2. Stand-by SW Function

(pin 4)

By means of controlling pin 4 (stand-by terminal)

to high and low, the power supply can be set to ON
and OFF. The threshold voltage of pin 4 is set at
about 3V

(typ.), and the power supply current is

about 2 mA (typ.) at the stand-by state.

Control Voltage of pin 4: V

Stand-by Power V

(V)

ON OFF 0~1.5

OFF ON 3~V

Adjustage of Stand-by SW

(1) Since

can directly be controlled to ON or OFF by the microcomputer, the switching relay can be

omitted.

(2) Since the control current is microscopic, the switching relay of small current capacity is satisfactory

for switching

Amp. 1

Input

Amp. 2A

Amp. 2B

Figure 1 Block Diagram

TA8276H

2002-02-13

3. Muting

Function

(pin 22)

By means of controlling pin 22 less than 0.5 V, it can make the audio muting condition.
The muting time constant is decided by R

and C

and these parts is related the pop noise at power

ON/OFF.
The series resistance; R1 must be set up less than 10 kW to get enough muting attenuation.

The muting function have to be controlled by a transistor, FET and m-COM port which has I

MUTE

> 250 mA

ability.
Pin 22 terminal voltage has the temperature characteristics of 4.6 V (low temperature) to 3.2 V (high
temperature).
Therefore, it is need to design with attention as using the microcontroller of which operating voltage is less
than 5 V.
Terminal 22 may not be pulled up and shall be controlled by OPEN/LOW.
When it is obliged to do, it must be pulled up via diode, because it has to defend flowing reverse current to
internal circuit of pin 22.

Conventional Method

Large current capacity switch

BATTERY

FROM

MICROCOMPUTER

BATTERY

RELAY

Small current capacity switch

BATTERY

Stand-By

DIRECTLY FROM
MICROCOMPUTER

BATTERY

Stand-By

Stand-by Switch Method

Figure 3

Figure 5 Mute Attenuation

-
-
-
-

MUTE

(V)

Point A voltage: VMUTE (V)

ATT V

MUTE

Mut

e

a

tte

ati

n A

(dB

)

10 k

5 k

VCC

13.2 V

10 W

1 kHz

400~30 kHz

100

0.4

0.8 1 1.2

1.6 2 2.4 2.8

Figure 4 Muting Function

I (100

MUTE

MUTE (OFF)

MUTE

I (100

MUTE

MUTE (OFF)

MUTE

TA8276H

2002-02-13

4. AUX

Input

(pin 16)

The pin 16 is for input terminal of AUX

amplifier.

The total gain is 0 dB by using of AUX amplifier.
Therefore, the m-COM can directly drive the

AUX amplifier.

BEEP sound or voice synthesizer signal can be

input to pin 16 directly.

When AUX function is not used, this pin must be

connected to PRE-GND (pin 13) via a capacitor.

Diagnosis Output

(pin 25)

This diagnosis output terminal of pin 25 has open collector output structure on chip as shown in Figure 7.

In case diagnosis circuit that detect unusual case is operated, NPN Tr. (Q1) is turned on.
It is possible to protect all the system of apparatus as well as power IC protection.

In case of being unused this function, use this IC as open-connection on pin 25.

5.1

In Case of Shorting Output to V

/GND or Over Voltage Power Supplied

NPN Tr. (Q1) is turned on.
Threshold of over voltage protection: V

= 22 V (typ.)

5.2

In Case of Shorting Output to Output

NPN Tr. (Q1) is turned on and off in response to the input signal voltage.

5 V

LED/LCD

ALAME

REGULATOR

OFF

(Flashing)

(Announcement from a speaker.)

(Relay

OFF)

-COM

MEMORY (Count and record)

Figure 8 Application 1

Figure 7 Self Diagnosis Output

OUTPUT CLIP

DETECTOR

OUTPUT SHORT

PROTECTOR

OVER VOLTAGE

PROTECTOR

5 V

pin 25: Open collector output (active low)

Q1 is turned on

GND

5 V

V25

Figure 6 AUX Input

20 dB AMP.

OUT (

)

OUT (

)

AUX-IN

20 dB

AUX AMP

-COM

TA8276H

2002-02-13

5.3

Prevention of speaker burning accident (In Case of Rare Short Circuit of Speaker)

When the direct current resistance between OUT + and OUT - terminal becomes 1 W or less and output

current over 4 A flows, this IC makes a protection circuit operate and suppresses the current into a speaker.

This system makes the burning accident of the speaker prevent as below mechanism.

Abnormal output offset voltage (voltage between OUT + and OUT -) over 4 V is made by the external

circuit failure.(Note 1)

The speaker impedance becomes 1 W or less as it is in a rare short circuit condition.

The current more than 4 A flows into the speaker and the speaker is burned.

Note 1: It is appeared by biased input DC voltage

(for example, large leakage of the input capacitor, short-circuit between copper patterns of PCB.)

5.4 Applications

When output terminals short-circuit to V

or GND, the voltage of 25pin is fixed to "L".

And when shorting OUT + to OUT -, "L" and "H" are switched according to an input signal.

Therefore, it is possible to judge how the power IC condition is if a micro-controller detects the

25pin voltage that is smoothed out with LPF.

It is recommend that the threshold voltage (Vth) is set up as higher as possible because output level

of LPF is changed according to an input signal.
(for example, Vth is set up to 4 V if 25pin is pulled up to 5 V line.)

Current into a speaker

Speaker impedance

Less than 4

Figure 9

About 1

Operating point of protector

Output voltage of L.P.F.

Output power

5 V

Figure 10

Operating point of protector

TA8276H

2002-02-13

Output Clip Detection Function

(pin 25)

The output clip detection terminal of pin 25 has the open collector output structure on chip as shown in

Figure 11. In case that the output waveform is clipping, the clip detection circuit is operated and NPN Tr. is
turned on.

It is possible to improve the audio quality with controlling the volume, tone control circuit through L.P.F.

smoothing circuit as shown in Figure 11.

In case of being unused this function, use this IC as open connection on pin 25.

(A)

5 V

(A) Output (AC wave form)

(B)

(B) Clip Detector Circuit
(internal)

(C)

(B) Clip Detector Terminal
(pin 25)

GND

Figure 12 Clip Detection

Figure 11

pin 25: Open collector output (active low)

OUTPUT CLIP

DETECTOR

5 V

L.P.F.

SMOOTHING

CIRCUIT

VOLUME CONTROL CIRCUIT

TONE CONTROL CIRCUIT

(Application)

TA8276H

2002-02-13

Maximum Ratings

(Ta

=
=
=
=

25°C)

Characteristics Symbol

Rating

Unit

Peak supply voltage (0.2 s)

CC (surge)

50 V

DC supply voltage

CC (DC)

25 V

Operation supply voltage

CC (opr)

18 V

Output current (peak)

O (peak)

9 A

Power dissipation

(Note 1)

125

Operation temperature

opr

40~85 °C

Storage temperature

stg

55~150 °C

Note 1: Package thermal resistance

j-T

1°C/W (typ.)

(Ta

25°C, with infinite heat sink)

Electrical Characteristics

(unless otherwise specified, V

=
=
=
=

13.2 V, f

=
=
=
=

1 kHz, R

=
=
=
=

, Ta

=
=
=
=

25°C)

Characteristics Symbol

Test

Circuit

Test Condition

Min

Typ.

Max

Unit

Quiescent current

CCQ

200 400

OUT

MAX (1)

14.4 V, max Power

OUT

MAX (2)

13.7 V, max Power

OUT

(1)

14.4 V, THD

10%

Output power

OUT

(2)

THD

10%

Total harmonic distortion

THD

OUT

5 W

0.02 0.2 %

Voltage gain

OUT

0.775 V

rms

dBm) 24 26 28

Voltage gain ratio

OUT

0.775 V

rms

(0 dBm)

1.0 0 1.0

(1)

, DIN45405

0.12

Output noise voltage

(2)

, BW

20 Hz~20 kHz

0.10 0.35

rms

Ripple rejection ratio

R.R.

rip

100 Hz, Rg

620

rip

0.775 V

rms

(0 dBm)

40 50

Cross talk

C.T.

620

OUT

0.775 V

rms

(0 dBm)

Output offset voltage

OFFSET

150 0 150

Input resistance

Stand-by current

Stand-by

condition

2 10

Power:

3.0

Stand-by control voltage

Power:

OFF

1.5

Mute:

OFF

Open

Mute control voltage

(Note 2)

Mute: ON, R

10 k

0.5 V

Mute attenuation

ATT M

Mute: ON,
V

OUT

7.75 Vrms (20 dBm) at

Mute:

OFF.

80 90

Note 2: Muting function have to be controlled by open and low logic, which logic is a transistor, FET and

-COM port

of I

MUTE

250

A ability.

This means than the mute control terminal : pin 22 must not be pulled-up.

TA8276H

2002-02-13

Test Circuit

IN1

IN2

IN3

IN4

PRE-GND

OUT1 (

)

PW-GND1

OUT1 (

)

OUT2 (

)

PW-GND2

OUT2 (

)

OUT3 (

)

PW-GND3

OUT3 (

)

OUT4 (

)

PW-GND4

OUT4 (

)

TAB

CC1

CC2

: PRE-GND

: PW-GND

STBY

CLIP OUT

DIAGNOSIS

OUT

RIP MUTE

3900

0.22

10 k

0.22

AUX IN

0.22

TA8276H

2002-02-13

Qui

e
s
c
en

t
cu

ent

CCQ

)

Output power P

OUT

(W)

T.H.D P

OUT

T
o
t
a
l

ha

oni

c

di

ti
on

.
H

.
D

)

Power supply voltage VCC (V)

CCQ

Frequency f (Hz)

T.H.D f

T
o
t
a
l

ha

oni

c

di

ti
on

.
H

.
D

)

Output power P

OUT

(W)

T.H.D P

OUT

T
o
t
a
l

ha

oni

c

di

ti
on

.
H

.
D

)

400

100

200

300

VIN

100

100 k

0.001

1 k

0.01

0.1

10 k

OUT2

OUT1

OUT4

OUT3

VCC

13.2 V

Pout

5 W

0.1

100

0.01

0.1

100

10 kHz

1 kHz

100 Hz

VCC

13.2 V

0.1

100

0.01

0.1

100

13.2 V

16.0 V

9.0 V

1 kHz

TA8276H

2002-02-13

o
s
s

t
a
lk

C.T

.
(

d
B)

o
s
s

t
a
lk

C.T

.
(

d
B)

Signal source resistance Rg (

)

Outp

ut noi

s
e

v
o
l
t
a

(

rms

)

Frequency f (Hz)

R.R. f

i
ppl

rej

e
cti

rati

o R

.
R

.
(

d
B

)

Frequency f (Hz)

C.T. f (OUT1)

o
s
s

t
a
lk

C.T

.
(

d
B)

Frequency f (Hz)

C.T. f (OUT2)

Frequency f (Hz)

C.T. f (OUT3)

Frequency f (Hz)

C.T. f (OUT4)

o
s
s

t
a
lk

C.T

.
(

d
B)

100

100 k

1 k

10 k

VCC

13.2 V

VOUT

0.775 Vrms (0 dBm)

620

OUT1

OUT2, 3

OUT1

OUT4

100

100 k

1 k

10 k

VCC

13.2 V

VOUT

0.775 Vrms (0 dBm)

620

OUT2

OUT1

OUT2

OUT3, 4

100

100 k

1 k

10 k

VCC

13.2 V

620

Vrip

0dBm

100

100 k

1 k

10 k

VCC

13.2 V

VOUT

0dBm

620

OUT3

OUT4

OUT3

OUT2

OUT3

OUT1

OUT4

OUT1, 2

100

100 k

1 k

10 k

VCC

13.2 V

VOUT

0dBm

620

OUT4

OUT3

100

100 k

300

1 k

200

10 k

100

150

250

VCC

13.2 V

20 Hz~20 kHz

TA8276H

2002-02-13

Frequency f (Hz)

o
l
t
ag

e g

a
i
n

G

(dB

)

Output power P

OUT

/ch (C)

OUT

o
w

e
r
di

ssi

p
a
ti
on

(

)

Ambient temperature Ta (°C)

MAX Ta

l
l
o
w

abl

e p

o
w

r di

s
s
i
pati

.
(w

)

150

120

100

50 125

INFINITE HEAT SINK

1°C/W

HEAT SINK (R

3.5°C/W)

4.5°C/W

NO HEAT SINK

39°C/W

100

100 k

1 k

10 k

VCC

13.2 V

VOUT

0.775 Vrms (0 dBm)

15 20

9 V

13.2 V

16 V

1 kHz

TA8276H

2002-02-13

TOSHIBA is continually working to improve the quality and reliability of its products. Nevertheless, semiconductor
devices in general can malfunction or fail due to their inherent electrical sensitivity and vulnerability to physical
stress. It is the responsibility of the buyer, when utilizing TOSHIBA products, to comply with the standards of
safety in making a safe design for the entire system, and to avoid situations in which a malfunction or failure of
such TOSHIBA products could cause loss of human life, bodily injury or damage to property.
In developing your designs, please ensure that TOSHIBA products are used within specified operating ranges as
set forth in the most recent TOSHIBA products specifications. Also, please keep in mind the precautions and
conditions set forth in the "Handling Guide for Semiconductor Devices," or "TOSHIBA Semiconductor Reliability
Handbook" etc..

The TOSHIBA products listed in this document are intended for usage in general electronics applications
(computer, personal equipment, office equipment, measuring equipment, industrial robotics, domestic appliances,
etc.). These TOSHIBA products are neither intended nor warranted for usage in equipment that requires
extraordinarily high quality and/or reliability or a malfunction or failure of which may cause loss of human life or
bodily injury ("Unintended Usage"). Unintended Usage include atomic energy control instruments, airplane or
spaceship instruments, transportation instruments, traffic signal instruments, combustion control instruments,
medical instruments, all types of safety devices, etc.. Unintended Usage of TOSHIBA products listed in this
document shall be made at the customer's own risk.

This product generates heat during normal operation. However, substandard performance or malfunction may
cause the product and its peripherals to reach abnormally high temperatures.
The product is often the final stage (the external output stage) of a circuit. Substandard performance or
malfunction of the destination device to which the circuit supplies output may cause damage to the circuit or to the
product.

The products described in this document are subject to the foreign exchange and foreign trade laws.

The information contained herein is presented only as a guide for the applications of our products. No
responsibility is assumed by TOSHIBA CORPORATION for any infringements of intellectual property or other
rights of the third parties which may result from its use. No license is granted by implication or otherwise under
any intellectual property or other rights of TOSHIBA CORPORATION or others.

The information contained herein is subject to change without notice.

000707EBF

RESTRICTIONS ON PRODUCT USE

Part Number TA8276H