Datasheet TDA7293V Datasheet (SGS Thomson Microelectronics)

TDA7293
120V - 100W DMOS AUDIO AMPLIFIER WITHMUTE/ST-BY
VERY HIGH OPERATING VOLTAGE RANGE (±50V)
DMOSPOWERSTAGE HIGH OUTPUT POWER (100W @ THD =
10%, R
L =8
,VS=±40V)
MUTING/STAND-BYFUNCTIONS NO SWITCHON/OFF NOISE VERYLOW DISTORTION VERYLOW NOISE SHORTCIRCUIT PROTECTION THERMALSHUTDOWN CLIPDETECTOR MODULARITY (MORE DEVICES CAN BE
EASILY CONNECTED IN PARALLEL TO DRIVE VERYLOW IMPEDANCES)
DESCRIPTION
The TDA7293 is a monolithic integrated circuit in Multiwatt15 package, intended for use as audio class AB amplifier in Hi-Fi field applications (Home Stereo, self powered loudspeakers, Top-
Figure 1: Typical Applicationand Test Circuit
MULTIPOWER BCD TECHNOLOGY
Multiwatt15
ORDERING NUMBER: TDA7293V
class TV). Thanks to the wide voltage range and to the high out current capability it is able to sup­ply the highest powerinto both4and 8loads.
The built in muting function with turn on delay simplifiesthe remote operation avoiding switching on-off noises. Parallel mode is made possible by connecting more device through of pin11. High output power can be deliveredto verylow impedance loads, so optimizingthe thermal dissipation ofthe system.
VMUTE
VSTBY
December1999
C7 100nF C6 1000µF
R3 22K
C2
R2
22µF
680
C1 470nF
R1 22K
R5 10K
R4 22K
C3 10µFC410µF
IN- 2
IN+
3
4
SGND (**)
10
MUTE
9
STBY
(*) see Application (**) for SLAVE function
note
MUTE
STBY
1 STBY-GND
+Vs
BUFFER DRIVER
713
11
-
+
THERMAL
SHUTDOWN
-Vs -PWVs
C9 100nF C8 1000µF
PROTECTION
158
-Vs
+PWVs+Vs
S/C
14
12
6 5
D97AU805A
OUT
BOOT LOADER
C5
22µF
BOOTSTRAP
CLIP DET
(*)
VCLIP
1/13
TDA7293
PIN CONNECTION (Top view)
TAB CONNECTED TO PIN 8
15 14 13 12 11 10
9 8 7 6 5 4 3 2 1
D97AU806
-VS(POWER) OUT
(POWER)
+V
S
BOOTSTRAP LOADER BUFFER DRIVER MUTE STAND-BY
-V
(SIGNAL)
S
+VS(SIGNAL) BOOTSTRAP CLIP AND SHORT CIRCUIT DETECTOR SIGNAL GROUND NON INVERTING INPUT INVERTING INPUT STAND-BY GND
QUICK REFERENCEDATA
Symbol Parameter Test Conditions Min. Typ. Max. Unit
V
S
G
LOOP
P
tot
SVR Supply Voltage Rejection 75 dB
Supply Voltage Operating ±12 æ 50 V Closed Loop Gain 26 40 dB Output Power VS=±45V; RL=8Ω; THD = 10% 140 W
= ±30V; RL =4Ω; THD = 10% 110 W
V
S
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Value Unit
V
S
V V
2 -V3 Maximum Differential Inputs ±30 V
V
V V V V V
V
10 11 Buffer Voltage Referred to -VS 120 V
V V
12
I
O
P
tot
T
op
T
stg,Tj
Supply Voltage (No Signal) V
1 2
3 4
5 Clip Detector Voltage Referred to -VS 120 V 6 9
STAND-BY
Input Voltage (inverting) Referred to -V
Input Voltage (non inverting) Referred to -V Signal GND Voltage Referred to -V
Bootstrap Voltage Referred to -V Stand-by Voltage Referred to -V Mute Voltage Referred to -V
Bootstrap Loader Voltage Referred to -V
GND Voltage Referred to -VS(pin 8) 90 V
S
S
S
S
S
S
S
Output Peak Current 10 A Power Dissipation T
=70°C50W
case
Operating Ambient Temperature Range 0 to 70 Storage and Junction Temperature 150
60 V
±
90 V
90 V 90 V
120 V 120 V 120 V
100 V
THERMAL DATA
Symbol Description Typ Max Unit
R
th j-case
Thermal Resistance Junction-case 1 1.5
° °
C/W
°
C C
2/13
TDA7293
ELECTRICALCHARACTERISTICS(Refer to the Test Circuit VS= ±40V,RL=8,Rg=50Ω;
T
=25°C,f = 1 kHz; unlessotherwise specified).
amb
Symbol Parameter Test Condition Min. Typ. Max. Unit
V
V
I P
Supply Range
S
Quiescent Current 30 mA
I
q
Input Bias Current 0.3 1
I
b
Input Offset Voltage -10 10 mV
OS
Input Offset Current 0.2
OS
RMS Continuous Output Power d = 1%:
O
R
=4Ω; VS = ± 29V,
L
d = 10% R
=4Ω ;VS=±29V
L
d Total Harmonic Distortion (**) P
I
Current Limiter Threshold 6.5 A
SC
= 5W; f = 1kHz
O
P
=0.1to 50W;f = 20Hz to 15kHz
O
SR Slew Rate 15 V/µs
G G
e
Open Loop Voltage Gain 80 dB
V
Closed Loop Voltage Gain (1) 30 dB
V
Total Input Noise A = curve
N
f = 20Hz to 20kHz
R
SVR Supply Voltage Rejection f = 100Hz; V
T
Input Resistance 100 k
i
= 0.5Vrms 75 dB
ripple
Thermal Protection DEVICE MUTED 150
S
DEVICE SHUT DOWN 160 °C
STAND-BY FUNCTION (Ref: to pin 1)
V V
ATT
I
q st-by
ST on ST off
Stand-by on Threshold 1.5 V Stand-by off Threshold 3.5 V Stand-by Attenuation 70 90 dB
st-by
Quiescent Current @ Stand-by 0.5 mA
MUTE FUNCTION (Ref: to pin 1)
V V
ATT
Mute on Threshold 1.5 V
Mon
Mute off Threshold 3.5 V
Moff
Mute AttenuatIon 60 80 dB
mute
CLIP DETECTOR
Duty Duty Cycle ( pin 5) THD = 1% ; RL = 10K
to 5V 10 %
THD = 10% ; RL = 10KΩto 5V
I
CLEAK
SLAVE FUNCTION pin 4 (Ref: to pin 8 -V
V
Slave
V
Master
Note (1): GVmin ≥ 26dB Note: Pin 11 only for modular connection.Max external load 1M/10 pF,only for test purpose
Note (**): Tested with optimized Application Board (see fig. 2)
SlaveThreshold 1V Master Threshold 3 V
PO = 50W 1 µA
)
S
12
±
50 V
±
80 80
100 100
0.005
0.1
1 25
40 %
A
µ
A
µ
W
W
% %
V
µ
V
µ
C
°
3/13
TDA7293
Figure 2: Typical Application P.C. Boardand ComponentLayout (scale1:1)
4/13
TDA7293
APPLICATIONSUGGESTIONS(seeTest andApplication Circuitsof the Fig. 1)
The recommendedvalues of the external components are those shown on the application circuit of Fig­ure 1. Different valuescan be used; the followingtable can help the designer.
COMPONENTS SUGGESTED VALUE PURPOSE
LARGER THAN
SUGGESTED
R1 (*) 22k INPUT RESISTANCE INCREASE INPUT
IMPEDANCE
R2 680
CLOSED LOOP GAIN
DECREASE OF GAIN INCREASE OF GAIN
SMALLER THAN
SUGGESTED
DECREASE INPUT
IMPEDANCE
SET TO 30dB (**)
R3 (*) 22k INCREASE OF GAIN DECREASE OF GAIN
R4 22k ST-BY TIME
CONSTANT
LARGER ST-BY
ON/OFF TIME
SMALLER ST-BY
ON/OFF TIME;
POP NOISE
R5 10k MUTE TIME
CONSTANT
C1 0.47µF INPUT DC
DECOUPLING
LARGER MUTE
ON/OFF TIME
SMALLER MUTE
ON/OFF TIME HIGHER LOW
FREQUENCY
CUTOFF
C2 22µF FEEDBACK DC
DECOUPLING
HIGHER LOW
FREQUENCY
CUTOFF
C3 10µF MUTE TIME
CONSTANT
C4 10µF ST-BY TIME
CONSTANT
LARGER MUTE
ON/OFF TIME
LARGER ST-BY
ON/OFF TIME
SMALLER MUTE
ON/OFF TIME
SMALLER ST-BY
ON/OFF TIME;
POP NOISE
C5 22µFXN (***) BOOTSTRAPPING SIGNAL
C6, C8 1000µF SUPPLY VOLTAGE
C7, C9 0.1µF SUPPLY VOLTAGE
(*) R1 = R3 for pop optimization (**) Closed Loop Gain has to be≥26dB (***) Multiplay this value for thenumber of modular part connected
Slave function:pin 4 (Ref to pin8 -VS)
+3V
-V
S
+1V
-V
S
-V
S
MASTER
UNDEFINED
SLAVE
D98AU821
DEGRADATION AT LOW FREQUENCY
BYPASS
DANGER OF
BYPASS
OSCILLATION
Note:
If in the application, the speakers are connected via long wires, it is a good rule to add between the output and GND, a BoucherotCell, in order to avoid dangerous spurious oscillations when the speakersterminal are shorted.
The suggested Boucherot Resistor is 3.9Ω/2W and the capacitoris 1µF.
5/13
TDA7293
INTRODUCTION
In consumer electronics, an increasing demand has arisen for very high power monolithic audio amplifiers able to match, with a low cost, the per­formance obtained from the best discrete de­signs.
The task of realizing this linear integrated circuit in conventional bipolar technology is made ex­tremely difficult by the occurence of 2nd break­down phoenomenon. It limits the safe operating area (SOA) of the power devices, and, as a con­sequence, the maximum attainable output power, especiallyin presenceof highlyreactive loads.
Moreover, full exploitation of the SOA translates into a substantial increase in circuit and layout complexity due to the need of sophisticated pro­tection circuits.
To overcome these substantial drawbacks, the use of power MOS devices, which are immune from secondarybreakdown is highly desirable.
The device described has therefore been devel­oped in a mixed bipolar-MOS high voltage tech­nology called BCDII100/120.
1) Output Stage
The main design task in developpinga power op­erational amplifier, independently of the technol­ogy used, is that of realization of the output stage.
The solution shown as a principle shematic by Fig3 represents the DMOS unity - gain output buffer of the TDA7293.
This large-signal, high-power buffer must be ca­pable of handling extremely high current and volt­age levels while maintaining acceptably low har­monic distortion and good behaviour over
frequency response; moreover, an accurate con­trol of quiescentcurrent is required.
A local linearizing feedback, provided by differen­tial amplifier A, is used to fullfilthe above require­ments, allowing a simple and effective quiescent currentsetting.
Proper biasing of the power output transistors alone is howevernot enough to guarantee the ab­senceof crossoverdistortion.
While a linearization of the DC transfer charac­teristic of the stage is obtained, the dynamic be­haviour of the systemmust be taken into account.
A significant aid in keeping the distortion contrib­uted by the final stage as low as possible is pro­vided by the compensation scheme, which ex­ploits the direct connection of the Miller capacitor at the amplifier’s output to introduce a local AC feedbackpath enclosing the outputstage itself.
2) Protections
In designing a power IC, particular attention must be reserved to the circuits devoted to protection of the device from short circuit or overload condi­tions.
Due to the absence of the 2nd breakdown phe­nomenon, the SOA of the power DMOS transis­tors is delimited only by a maximum dissipation curve dependent on the duration of the applied stimulus.
In order to fully exploit the capabilities of the power transistors, the protection scheme imple­mented in this device combines a conventional SOA protection circuit with a novellocal tempera­ture sensing technique which ” dynamically” con­trols the maximumdissipation.
Figure 3: PrincipleSchematic of a DMOSunity-gainbuffer.
6/13
Figure 4: Turn ON/OFFSuggestedSequence
+Vs
(V)
+40
-40
-Vs
VIN
(mV)
V
ST-BY
PIN #9
(V)
5V
TDA7293
V
MUTE
PIN #10
(V)
IQ
(mA)
V
OUT (V)
5V
OFF
ST-BY
PLAY
MUTE MUTE
In addition to the overload protection described above, the device features a thermal shutdown circuit which initially puts the device into a muting state (@ Tj = 150 Tj = 160
o
C).
o
C) and then into stand-by (@
Full protectionagainst electrostaticdischarges on every pin is included.
Figure 5:
SingleSignal ST-BY/MUTEControl
Circuit
MUTE STBY
MUTE/
ST-BY
20K
10K 30K
1N4148
10µF10µF
D93AU014
3) OtherFeatures
The device is provided with both stand-by and
ST-BY OFF
D98AU817
mute functions, independently driven by two CMOSlogic compatible input pins.
The circuits dedicated to the switching on and off of the amplifier have been carefully optimized to avoid any kindof uncontrolledaudible transient at the output.
The sequence that we recommend during the ON/OFFtransientsis shown by Figure 4.
The application of figure 5 shows thepossibility of using only one command for both st-by and mute functions. On both the pins, the maximum appli­cable range corresponds to the operating supply voltage.
APPLICATION INFORMATION
HIGH-EFFICIENCY Constraints of implementinghigh power solutions
are the power dissipation and the size of the power supply. These are both due to the low effi­ciency of conventional AB class amplifier ap­proaches.
Here below (figure 6) is described a circuit pro­posal for a high efficiency amplifier which can be adopted for both HI-FI and CAR-RADIO applica­tions.
7/13
TDA7293
The TDA7293 is a monolithic MOS power ampli­fier which can be operated at 100V supplyvoltage (120V with no signal applied) while delivering out­put currentsup to ±6.5 A. This allows the use of this device as a very high power amplifier (up to 180W as peak power with T.H.D.=10 % and Rl = 4 Ohm);the only drawback is the power dissipation, hardly manageable in the above power range. The typical junction-to-case thermal resistance of the TDA7293 is 1 avoid that, in worst case conditions, the chip tem­perature exceedes150 of the heatsink must be 0.038 bient temperatureof 50
o
C/W (max= 1.5oC/W). To
o
C, the thermal resistance
o
o
C).
C/W (@ max am-
As the above value is pratically unreachable; a high efficiency system is needed in those cases where the continuousRMS output power is higher than 50-60 W. The TDA7293 was designed to work also in higher efficiencyway. For this reason there are four power supply pins: two intended for the signal part and two for the power part. T1 and T2 are two power transistors that only operate when the output power reaches a certain threshold (e.g. 20 W). If the output power in­creases, these transistors are switched on during the portion of the signal where more output volt­age swing is needed, thus ”bootstrapping” the power supply pins(#13 and #15).
The current generators formed by T4, T7, zener diodes Z1, Z2 and resistors R7,R8 define the minimum drop across the power MOS transistors of the TDA7293. L1, L2, L3 and the snubbersC9, R1 and C10, R2 stabilize the loops formed by the ”bootstrap” circuits and the output stage of the TDA7293.
By considering again a maximum average output power (music signal) of 20W, in case of the high efficiency application, the thermal resistance value needed from the heatsink is
o
C/W (Vs =±50 V and Rl= 8 Ohm).
2.2 All components (TDA7293 and power transis­tors T1 and T2) can be placed on a 1.5
o
C/W heatsink, with the power darlingtons electrically insulatedfrom the heatsink. Since the total power dissipation is less than that of a usual class AB amplifier, additional cost sav­ings can be obtained while optimizing the power supply, even witha high heatsink.
BRIDGE APPLICATION
Another application suggestion is the BRIDGE configuration,where two TDA7293 are used. In this application, the value of the load must not be lower than 8 Ohm for dissipation and current capability reasons. A suitable field of application includes HI-FI/TV subwoofersrealizations.
The main advantagesoffered by this solutionare:
- High power performanceswith limited supply voltagelevel.
- Considerablyhigh output power even with high loadvalues (i.e. 16 Ohm).
With Rl= 8 Ohm, Vs = ±25V the maximum output power obtainable is 150 W, while with Rl=16 Ohm,Vs = ±40V the maximumPout is 200W.
APPLICATION NOTE: (ref. fig. 7) ModularApplication (moreDevices in Parallel)
The use of the modular application lets very high power be delivered to very low impedance loads. The modular application implies one device to act as a master and the others as slaves.
The slave power stages are driven by the master device and work in parallel all together, while the input and the gain stages of the slave device are disabled, the figure below shows the connections required to configure two devices to work to­gether.
The master chip connections are the same as the normal single ones.
The outputs can be connected together with-
out the need of any ballast resistance.
The slave SGND pin must be tied to the nega­tive supply.
The slave ST-BY pin must be connected to ST-BYpin.
The bootstrap lines must be connected to­gether and the bootstrap capacitor must be in­creased: for N devices the boostrap capacitor must be 22µF times N.
The slave Mute and IN-pinsmust be grounded.
THE BOOTSTRAP CAPACITOR
For compatibility purpose with the previous de­vices of the family, the boostrap capacitor can be connectedboth between the bootstrappin (6) and the output pin (14) or between the boostrap pin (6) and the bootstraploader pin (12). When the bootcap is connected between pin 6 and 14, the maximum supply voltage in presence of output signal is limited to 100V, due the boot­strapcapacitor overvoltage. When the bootcap is connected between pins 6 and 12 the maximum supply voltageextend to the full voltagethat thetechnologycan stand:120V.
This is accomplished by the clamp introduced at the bootstrap loader pin (12): this pin follows the output voltage up to 100V and remains clamped at 100V for higher output voltages. This feature lets the output voltage swing up to a gate-source voltagefrom the positive supply (V
S -3 to 6V)
8/13
Figure 6: High EfficiencyApplication Circuit
TDA7293
+50V
D6
1N4001
PLAY
ST-BY
D5
1N4148
D1 BYW98100
C12 330nF
IN
C13 10µF
R13 20K
R14 30K
R15 10K
10µF
D2 BYW98100
R20 20K
R21 20K
+25V
GND
-25V
-50V
C1
1000µF
63V
C2
1000µF
63V
C3
100nF
C4
100nF
C5
1000µF
35V
C6
1000µF
35V
C7
100nF
R22 10K
R23 10K
C8
100nF
C9
330nF
C10
330nF
D7
1N4001
R1
2
R2
2
Figure 6a: PCBand ComponentLayout of the fig. 6
C14
R12 13K
3
4
TDA7293
9
1
815
10
137
BDX53A
R17 270
L1 1µH
2
14
6
12
L2 1µH
R19 270
BDX54A
T3
BC394
T1
D3 1N4148
R3 680
R16 13K
C15
22µF
D4 1N4148
T2
T6
BC393
C11 22µF
L3 5µH
R18 270
R4 270
BC393
Z1 3.9V
Z2 3.9V
BC394
R9 270
R5
270
T4
T7
R6
20K
R7
3.3K
R8
3.3K
R10 270
D97AU807C
T5
BC393
C16
1.8nF
C17
1.8nF
T8
BC394
R11 20K
OUT
P
ot
9/13
TDA7293
Figure 6b:
PCB - SolderSide of thefig. 6.
Figure 7: Modular ApplicationCircuit
MASTER
VMUTE
VSTBY
SLAVE
C2
22µF
R1 22K
R5 10K
R4 22K
R2
680
C1 470nF
R3 22K
IN- 2
IN+
SGND
MUTE
STBY
C4 10µF
C3 10µF
IN- 2
IN+ 3
SGND
MUTE
STBY
C7 100nF C6 1000µF
BUFFER
DRIVER
713
-
3
4
10
9
4
10 9
+
MUTE STBY
1 STBY-GND
C7 100nF C6 1000µF
+
MUTE STBY
1 STBY-GND
THERMAL
SHUTDOWN
-Vs -PWVs
C9 100nF C8 1000µF
BUFFER
DRIVER
713
-
THERMAL
SHUTDOWN
-Vs -PWVs
C9 100nF C8 1000µF
+Vs
PROTECTION
158
-Vs +Vs
PROTECTION
158
-Vs
+PWVs+Vs
14
OUT
BOOT
12
LOADER
6
BOOTSTRAP
S/C
+PWVs+Vs
S/C
5
14
12
6 5
CLIP DET
OUT
BOOT LOADER
BOOTSTRAP
C5
47µF
D97AU808C
C10
100nF
R7 2
11
11
10/13
TDA7293
Figure 8a: ModularApplication P.C. Boardand ComponentLayout (scale 1:1) (ComponentSIDE)
Figure 8b: ModularApplication P.C. Board and ComponentLayout (scale1:1) (SolderSIDE)
11/13
TDA7293
DIM.
Dia1 3.65 3.85 0.144 0.152
MIN. TYP. MAX. MIN. TYP. MAX.
A 5 0.197 B 2.65 0.104 C 1.6 0.063 D 1 0.039 E 0.49 0.55 0.019 0.022 F 0.66 0.75 0.026 0.030
G 1.02 1.27 1.52 0.040 0.050 0.060 G1 17.53 17.78 18.03 0.690 0.700 0.710 H1 19.6 0.772 H2 20.2 0.795
L 21.9 22.2 22.5 0.862 0.874 0.886 L1 21.7 22.1 22.5 0.854 0.870 0.886 L2 17.65 18.1 0.695 0.713 L3 17.25 17.5 17.75 0.679 0.689 0.699 L4 10.3 10.7 10.9 0.406 0.421 0.429 L7 2.65 2.9 0.104 0.114
M 4.25 4.55 4.85 0.167 0.179 0.191
M1 4.63 5.08 5.53 0.182 0.200 0.218
S 1.9 2.6 0.075 0.102
S1 1.9 2.6 0.075 0.102
mm inch
OUTLINEAND
MECHANICAL DATA
Multiwatt15 V
12/13
TDA7293
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13/13
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