Datasheet for Audio Amplifier Quad 4X35W St Micro IC 25-Pin Zip

Datasheet for Audio Amplifier Quad 4X35W St Micro IC 25-Pin Zip
TDA7454
4 x 35W HIGH EFFICIENCY QUAD BRIDGE
CAR RADIO AMPLIFIER
HIGH OUTPUT POWER CAPABILITY:
4 x 40W/4Ω MAX.
4 x 35W/4Ω EIAJ.
4 x 25W/4Ω @14.4V, 1KHz, 10%
4 x 60W/2Ω MAX.
2Ω DRIVING CAPABILITY
DUAL MODE OPERATING EXTERNALLY
PRESETTABLE: CONVENTIONAL CLASS AB MODE, HIGH EFFICIENCY MODE
LOW EXTERNAL COMPONENTS COUNT:
– NO BOOTSTRAP CAPACITORS
– NO EXTERNAL COMPENSATION
– INTERNALLY FIXED GAIN (26dB)
CLIPPING DETECTOR
ST-BY FUNCTION (CMOS COMPATIBLE)
MUTE FUNCTION (CMOS COMPATIBLE)
AUTOMUTE AT MINIMUM SUPPLY
VOLTAGE DETECTION
LOW RADIATION
Protections:
OUPUT SHORT CIRCUIT
TO GND; TO VS; ACROSS THE LOAD
3 STEPS OVERRATING CHIP TEMPERATURE WITH THERMAL WARNING
LOAD DUMP VOLTAGE
FORTUITOUS OPEN GND
BLOCK & APPLICATION DIAGRAM
MULTIPOWER BCD TECHNOLOGY
Flexiwatt 25
LOUDSPEAKER DC CURRENT
ESD
DESCRIPTION
The TDA7454 is a new BCD technology QUAD
BRIDGE type of car radio amplifier in Flexiwatt25
packagespecially intendedfor car radio applications.
Among the features, its superior efficiency performance coming from the internal exclusive
structure, makes it the most suitable device to
simplify the thermal management in high power
sets. The dissipated output power under average
listening condition is in fact reduced up to 50%
when compared to the level provided by conventional class AB solutions.
6
STD/HI- EFF
16
20
7
0.22µF
IN RIGHT
FRONT
11
VCC1
VCC2
8
RIGHT FRONT
+
9
ST-BY
IN RIGHT
REAR
4
0.22µF
VCC
-
13
S-GND
5
+
12
2
MUTE
22
0.22µF
IN LEFT
FRONT
15
100µF
RIGHT REAR
3
-
19
18
LEFT FRONT
+
17
SVR
0.22µF
10
1
21
IN LEFT
REAR
14
CD
25
TAB
+
24
23
LEFT REAR
D94AU172C
October 1999
1/13
TDA7454
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
Vop
Operating Supply Voltage
18
V
VS
DC Supply Voltage
28
V
Peak Supply Voltage (for t = 50ms)
40
V
IO
Output Peak Current (not repetitive t = 100µs)
8
A
IO
Output Peak Current (repetitive f > 10Hz)
6
A
Power Dissipation T case = 70°C
86
W
-55 to 150
°C
Vpeak
Ptot
Tstg, Tj
Storage and Junction Temperature
THERMAL DATA
Symbol
Rth j-case
Description
Thermal Resistance Junction-case
Max
PIN CONNECTION (Top view)
25
CD
24
PW GND LR
23
OUT LR-
22
MUTE
OUT LR+
20
VCC2
19
OUT LF-
18
PW GND LF
17
OUT LF+
16
STD/HEFF
15
IN LF
14
IN LR
13
S GND
12
IN RR
11
IN RF
10
SVR
9
OUT RF+
8
PW GND RF
7
OUT RF-
6
VCC1
OUT RR+
4
ST-BY
3
OUT RR-
2
PW GND RR
1
TAB
D94AU173A
2/13
Value
Unit
1
°C/W
TDA7454
ELECTRICAL CHARACTERISTICS (Refer to the test circuit V S = 14.4V; RL = 4Ω; f = 1KHz;
T amb = 25°C, unless otherwise specified
Symbol
Parameter
VS
Supply Voltage Range
Id
Total Quiescent Drain Current
Po
Output Power
Test Condition
Min.
Typ.
8
Max.
Unit
18
V
250
mA
60
140
THD = 10%
THD = 1%
23
18
25
20
W
W
THD = 10% RL = 2Ω;
THD = 1% RL = 2Ω;
40
28
42
30
W
W
Po EIAJ
EIAJ Output Power (*)
Vs = 13.7V
Vs = 13.7V, RL = 2Ω
32
50
35
52
W
W
Po max.
Max. Output Power (*)
Vs = 14.4V
Vs = 14.4V, RL = 2Ω
38
55
40
60
W
W
Total harmonic distortion
PO = 1W to 10W; STD MODE
PO = 1W; HE MODE
PO = 10W; HE MODE
0.03
0.04
0.1
0.3
0.3
0.5
%
%
%
R L = 2Ω; HE MODE; PO = 3W
R L = 2Ω; HE MODE; PO = 15W
0.06
0.15
0.3
0.5
%
%
KΩ
THD
CT
Cross Talk
45
55
R IN
Input Impedance
11
15
19
GV
Voltage Gain
25
26
27
dB
∆GV
EIN
Voltage Gain Match
1
dB
Output Noise Voltage
R g = 600Ω
150
mV
SVR
Supply Voltage Rejection
f = 300Hz; Vr = 1Vrms;
R g = 0 to 100Ω;
BW
Power Bandwidth
(–3dB)
A SB
Stand-by Attenuation
Vsb IN
Stand-by in Threshold
Vsb OUT
Stand-by Current Consumption
AM
Mute Attenuation
IN
Mute in Thereshold
VM
OUT
Mute out Threshold
IM
Mute pin Current (Sourced)
Mode Select Switch
100
45
52
Clip Det. out Current
(Pull up to 5V with 10KΩ)
dB
KHz
100
dB
1.5
V
100
µA
3.5
80
V
90
dB
1.5
V
10
µA
3.5
V = 0 to VS
VS max = 18V
Standard BTL Mode Op. (Vpin 16 )
-10
V
1
Open
High Efficiency Mode (Vpin 16 )
CD
dB
75
90
Stand-by out Threshold
Isb
VM
f = 1KHz to 10KHz
CD off: P Omin = 10W
CD on: THD = 5%
150
0.5
V
5
µA
µA
(*) Saturated square wave output.
3/13
TDA7454
Figure 1: Standard Test and Application Circuit.
C8
0.1µF
C9
2200µF
Vcc1
Vcc2
6
R1
20
4
ST-BY
10K
R2
9
C6
0.1µF
MUTE
7
22
10K
C7
1µF
5
C1
3
0.22µF
TDA7454
12
IN RR
17
C2 0.22µF
18
C3 0.22µF
21
14
IN LR
S-GND
24
13
(*)
SW1
(*) OPEN = STANDARD BTL
CLOSED=HI-EFF BTL
OUT LR
23
16
4/13
OUT LF
19
15
IN LF
C4 0.22µF
OUT RR
2
11
IN RF
OUT RF
8
10
25
SVR
1
TAB
C5
100µF
D95AU416
CLIP DET
TDA7454
Figure 2: P.C.B. and components layout of fig. 1 circuit. (1.25 :1 scale)
COMPONENTS &
TOP COPPER LAYER
BOTTOM COPPER LAYER
5/13
TDA7454
Figure 3: Quiescent Current vs. Supply Voltage
Id (mA)
240
Figure 4: Output Power vs. Supply Voltage
45
Po (W)
40
200
160
THD= 10 %
RL= 4 Ohm
f= 1 KHz
35
Vi = 0
RL = 4 Ohm
30
25
120
THD= 1 %
20
15
80
10
40
8
10
12
Vs (V)
14
16
18
Figure 5: Max. Output Power vs. Supply Voltage
60
55
50
45
40
35
30
25
20
15
10
5
Po (W)
8
9
10
11
12 13
Vs (V)
14
15
16
17
18
Figure 6: Output Power vs. Supply Voltage
50
Po (W)
45
THD = 10 %
40
RL= 4 Ohm
f= 1 KHz
RL = 2 Ohm
f = 1 KHz
35
30
THD = 1 %
25
20
15
10
8
9
10
11
12 13
Vs (V)
14
15
16
17
18
Figure 7: Max. Output Power vs. Supply Voltage
75
70
65
60
55
50
45
40
35
30
25
20
15
5
Po (W)
5
8
10
11
12
Vs (V)
13
14
15
Figure 8: THD vs. Output Power
10
RL= 2 Ohm
f= 1 KHz
9
THD (%)
RL = 4 Ohm
HI-EFF MODE
1
f = 10 KHz
0.1
f = 1 KHz
8
6/13
9
10
11
12
Vs (V)
13
14
15
16
0
0
1
Po (W)
10
16
TDA7454
Figure 10: Muting Attenuation vs. Vpin 22
Figure 9: THD vs. Output Power
10
THD (%)
RL= 2 Ohm
HI-EFFMODE
1
100
90
80
70
60
50
40
30
20
10
0
f = 10 KHz
0.1
f = 1 KHz
0
0
1
10
Po (W)
Figure 11: THD vs. Frequency
OUT ATTN
Po= 4 W
f= 20 to 20,000 Hz
0
0.5
1
1.5
2 2.5 3 3.5
Vpin22 (V)
4
4.5
5
Figure 12: Supply Voltage Rejection vs. Frequency
THD (%)
100
10
SVR (dB)
90
RL = 4 Ohm
Po = 1 W
HI-EFF MODE
1
80
Vripple= 1 Vrms
Rg= 0
70
60
50
0.1
40
30
0
10
100
1000
f (Hz)
10000
80
Po = 4 W
RL = 4 Ohm
Rg = 0
HI-E FF MODE
60
50
40
30
20
10
100
f (Hz)
1000
100
1000
10000
Figure 14: Power Dissipation and Efficiency vs.
Output Power
CROSSTALK (dB)
70
10
f (Hz)
Figure 13: Cross-Talk vs. Frequency
90
20
10000
Ptot (W)
70
65
Vs= 14.4 V
60
RL = 4 x 4 Ohm
55
f = 1 KHz
50
45
HI-EFF MODE
40
n
35
30
25
20
Ptot
15
10
5
0
0.1
1
Po (W)
n (%)
70
60
50
40
30
20
10
10
0
7/13
TDA7454
OPERATING PRINCIPLE.
Thanks to its unique operating principle, the
TDA7454 obtains a substantial reduction of power
dissipation from traditional class-AB amplifiers
without being affected by the massive radiation
effects and complex circuitry normally associated
with class-D solutions.
Its is composed of 8 amplifier blocks, making up
4 bridge-equivalent channels. Half of this structure is drafted in fig 15. These blocks continuously change their connections during every single signal event, according to the instantaneous
power demand. This means that at low volumes
(output power steadily lower than 2.5 W) the
TDA7454 acts as a Single Ended amplifier, condition where block “C” remains disabled and the
block “D” behaves like a buffer, which, by furnishing the correct DC biasing (half-Vcc) to each pair
of speakers, eliminate the needs of otherwise required output-decoupling capacitors. At the same
time, SW1 keeps closed. thus ensuring a common biasing point for L-R front / L-R rear speakers couples. As a result, the equivalent circuit becomes that of fig. 16.
The internal switches (SW1) are high-speed, dissipation-free power MOS types, whose realization
has been made possible by the ST- exclusive Bypolar-CMOS-DMOS mixed technology process
(BCD). From fig. 16 it can be observed that “A”
and “B” amplifiers work in phase opposition. Supposing their output have the same signal (equal
shape/amplitude), the current sourced by “B” will
be entirely sunk by “A”, while no current will flow
into “D”, causing no power dissipation in the latter.
“A” and “B” are practically configured as a bridge
whose load is constituted by Ra + Rb (= 8 Ohm, if
4 Ohm speakers are used), with considerable advantages in terms of power dissipation. Designating “A” and “B” for the reproduction of either
FRONT or REAR sections of the same channel
(LEFT or RIGHT), keeping the fader in centre position (same amplitude for FRONT and REAR
sections) and using the same speakers, as it happens during most of the time, will transpose this
best-case dissipation condition into practical applications.
To fully take advantage of the TDA7454’s low-dissipation feature, it is then especially important to
adopt some criteria in the channels assignment,
using the schematic of fig. 1 as a reference.
When the power demand increases to more than
2.5 W, all the blocks will operate as amplifiers,
SW1 is opened, leading to the seemingly conventional bridge configuration of fig. 17.
The efficiency enhancement is based upon the
concept that the average output power during the
reproduction of normal music/speech programs
will stand anywhere between 10 % and 15 % of
the rated power (@ THD= 10 %) that the amplifier
8/13
can deliver. This holds true even at high volumes
and frequent clipping occurrence.
Applied to the TDA7454 (rated power= 25 W),
this will result into an average output level of 2.5
- 3 W in sine-wave operation, region where the
dissipated power is about 50 % less than that of a
traditional amplifier of equivalent power class (see
TDA7454 vs. CLASS-AB characteristics, fig. 18).
Equally favourable is the case shown by fig. 19,
when gaussian-distributed signal amplitudes,
which best simulates the amplifier’s real working
conditions, are used.
APPLICATION HINTS (ref. to the circuit of fig. 1)
STAND-BY and MUTING (pins 4 & 22)
Both STAND-BY and MUTING pins are CMOScompatible. The current sunk by each of them is
about 1 µA. For pop prevention it is essential that
during TURN ON/OFF sequences the muting be
preventively inserted before making stand-by
transitions. But, if for any reason, either muting or
stand-by are not used, they have to be connected
to Vcc through a 100 Kohm (minimum) resistance.
The R-C networks values in fig. 1 (R1-C6 and R2C7) are meant to be the minimum-necessary for
obtaining the lowest pop levels possible. Any reductions (especially for R2-C7) will inevitably impair this parameter.
SVR (pin 10)
The duty of the SVR capacitor (C5) is double: assuring adequate supply-ripple rejection and controlling turn ON/OFF operations. Its indicated
value (100 uF) is the minimum-recommended to
correctly serve both the purposes.
INPUTS (pins 11-12-13-14)
The inputs are internally biased at half-Vcc level.
The typical input impedance is 15 KOhm, which
implies using Cin (C1-C2-C3-C4) = 220 nF for obtaining a theoretical minimum-reproducible frequency of 48 Hz (-3 dB). In any case, Cin values can be enlarged if a lower frequency bound
is desired, but, at any Cin enlargement must correspond a proportional increase of Csvr (C5), to
safeguard the on/off pop aspect.
The following table indicates the right values to be
used for Cin and Csvr, whose operating voltage
can be 10 V.
LOW FREQUENCY
ROLL-OFF (-3dB)
Cin (µF)
Csvr (µF)
48
0.22
100
22
0.47
220
16
0.68
330
11
1
470
TDA7454
Table 1: MODE SELECTION TABLE OPERATION OF THE DEVICE
1) STD/HI-EFF (pin 16 = OPEN)
STANDARD QUAD
BRIDGE MODE
HIGH-EFF QUAD
BRIDGE MODE
100
STANDARD QUAD
ST-BY MODE
SINGLE-ENDED MODE
150
Tchip (deg)
17 0
2) STD/HI-EFF (pin 16 = GND)
HIGH-EFF QUAD BRIDGE MODE
STANDARD QUAD
ST-BY MODE
SINGLE-ENDED MODE
150
Tchip (deg)
170
3) STD/HI-EFF (pin 16 connected as shown in the figure below.
STANDARD QUAD
BRIDGE MODE OR
HIGH-EFF MODE
(Theatsink dependent)
HIGH-EFF QUAD
BRIDGE MODE
STANDARD QUAD
ST-BY MODE
SINGLE-ENDED MODE
Tchip (deg)
100
150
17 0
Vref
STD/HI-EFF (pin 16)
NTC t(Theatsink)
D94AU174A
OUTPUT STAGE STABILITY
The TDA7454’s is intrinsically stable and will
properly drive any kind of conventional car-radio
speakers without the need of supplementary output compensation (e.g. Boucherot cells), thus allowing a drastic reduction of the external parts
whose number, abated to the essentials, reflects
that of traditional amplifiers. In this respect, perfect pin-to-pin compatibility with the entire SgsThomson’s 4-BTL family (TDA738X) exists.
STANDARD / HIGH-EFFICIENCY OPERATION
(pin 16)
The TDA7454’s operating mode can be selected
by changing the connection of pin 16, according
to table 1.
At low battery levels (<10 V), the device will automatically turn into STANDARD BRIDGE mode, independently from the status of pin 16.
Condition # 3 in table 1 is particularly useful when
the TDA7454’s operation has to be conditioned
by the temperature in other more heat-sensitive
devices in the same environment. The NTC resistor is a temperature sensor, to be situated near
the critical part(s), will appropriately drive pin 16
through a low-power transitor.
Initially the
TDA7454 can be set to operate as a STANDARD
BRIDGE, turning into HIGH EFFICIENCY mode
only if overheating is recognised in the critical
spot, thus reducing the overall temperature in the
circuit.
CLIPPING DETECTOR / DIAGNOSTIC (pin 25)
The TDA7454 is equipped with a diagnostic function whose output is available at pin 25. This pin
requires a pull-up resistor (10 KOhm min.) to a
DC source that may range from 5 V to Vcc. The
following events will be recognized and signaled
out:
Clipping
A train of negative-going pulses will appear, each
of them syncronized with every single clipping
event taking place in ant of the outputs.
A possible application consists of filtering / integrating the pulses and implement a routine for
automatically reducing / restoring the volume using microprocessor - driven audioprocessors, to
counteract the clipping sound-damagingeffects.
Overheating
Chip temperatures above 150 oC will be signaled
out at pin 25 in the form of longer-lasting pulses,
as the stepping back into the operating temperature requires some time.
9/13
TDA7454
This constitues a substantial difference from the
“clipping” situation, making the two information
unmistakable. Associated to a suitable external
circuitry, this “warning” signal could be used to
mute some portions of the I.C. (e.g. the rear
channels) or to attenuate the volume.
Short Circuit
Some kinds of short circuit (OUT - GND, OUTVcc), either present before the power-on or made
afterwards, will cause pin 25 to remain steadily
low as long as the faulty condition persists.
Short-circuits across the speakers will give intermittent (pulsed) signalling, proportional to the
output voltage amplitude.
External Layout Grounding
The 4 bridge stuctures have independent power
ground accesses (pins 2,8,18,24), while the signal ground is common to all of them (pin 13). The
Figure 15: TDA7454’s Half Structure
+
A
RF
TAB (pin 1) is connected to the chip substrate
and has to be grounded to the best-filtered
ground spot (usually nearby the minus terminal of
the Vcc-filtering electrolytic capacitor). This same
point should be used as the centre of a multi-track
star-like configuration, or, alternatively, as the origin of only two separate tracks, one for P-GND,
one for S-GND, each of them routed to their specific ground pin(s).
This will provide the right degree of separation
between P-GND and S-GND yet assuring the
(necessary) electrical connection between them.
The correct ground assignment for the each element of the circuit will then be:
POWER GND:
Battery (-), Supply filters (C8, C9), TAB (pin 1).
SIGNAL GND:
Pre-amplifier (Audiprocessor) ground, SVR capacitor (C5), muting/st-by capacitors (C6, C7).
Figure 16: Single Ended Operation (Po < 2.5W)
B
RR
INF
+
A
RF
INF
INR
SW1
Vf
C
+
Ron2
F-channel
-
R-channel
D97AU793
CONTROL
LOGIC
D97AU792
Figure 17: He Bridge Operation (Po < 2.5W)
+
A
RF
B
INR
RR
Vf
C
Vr
-
+
D
D97AU794
10/13
Vr
D
-
INF
B
RR
if
+
if-ir
D
INR
TDA7454
Figure 18: Power Dissipation (Sine-Wave)
Pdiss (W)
55
50
45
Vs = 14.4 V
RL = 4 x 4 Ohm
40
CLASS-AB
35
30
25
20
15
10
TDA7454
5
0
0.1
1
Po each channel (W)
Figure 19: Power Dissipation (Gaussian Signals)
45
Pdiss (W)
40
35
Vs = 14.4 V
RL = 4 x 4 Ohm
30
CLASS-AB
25
20
15
10
10
5
0
TDA7454
0.1
1
10
Pout each channel (W)
11/13
TDA7454
DIM.
MIN.
4.45
1.80
A
B
C
D
E
F (1)
G
G1
H (2)
H1
H2
H3
L (2)
L1
L2 (2)
L3
L4
L5
M
M1
N
O
R
R1
R2
R3
R4
V
V1
V2
V3
0.75
0.37
0.80
23.75
28.90
22.07
18.57
15.50
7.70
3.70
3.60
mm
TYP.
4.50
1.90
1.40
0.90
0.39
1.00
24.00
29.23
17.00
12.80
0.80
22.47
18.97
15.70
7.85
5
3.5
4.00
4.00
2.20
2
1.70
0.5
0.3
1.25
0.50
MAX.
4.65
2.00
MIN.
0.175
0.070
1.05
0.42
0.57
1.20
24.25
29.30
0.029
0.014
22.87
19.37
15.90
7.95
0.869
0.731
0.610
0.303
4.30
4.40
0.145
0.142
0.031
0.935
1.138
inch
TYP.
0.177
0.074
0.055
0.035
0.015
0.040
0.945
1.150
0.669
0.503
0.031
0.884
0.747
0.618
0.309
0.197
0.138
0.157
0.157
0.086
0.079
0.067
0.02
0.12
0.049
0.019
MAX.
0.183
0.079
OUTLINE AND
MECHANICAL DATA
0.041
0.016
0.022
0.047
0.955
1.153
0.904
0.762
0.626
0.313
0.169
0.173
5° (Typ.)
3° (Typ.)
20° (Typ.)
45° (Typ.)
Flexiwatt25
(1): dam-bar protusion not included
(2): molding protusion included
H
H1
V3
A
H2
O
H3
R3
L4
R4
V1
R2
L2
N
L3
R
L
L1
V1
V2
R2
D
R1
L5
R1
R1
E
G
V
G1
F
M
B
C
V
FLEX25ME
12/13
M1
TDA7454
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is
granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are
subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products
are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
The ST logo is a registered trademark of STMicroelectronics
 1999 STMicroelectronics – Printed in Italy – All Rights Reserved
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13/13
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