PHILIPS TDA8944AJ

TDA8944AJ
2 x 7 W BTL audio amplifier with DC gain control
Rev. 01 — 01 March 2002
Product data
M3D541
1. General description
The TDA8944AJ is a dual-channel audio power amplifier with DC gain control. It has
an output power of 2 × 7 W at an 8 Ω load and a 12 V supply. The circuit contains two
Bridge-Tied Load (BTL) amplifiers with an all-NPN output stage and standby/mute
logic. The overall gain can be adjusted from +30 dB down to −50 dB using a DC
control voltage. This feature can be used for volume control or a preset gain.
The TDA8944AJ comes in a 17-pin DIL-bent-SIL (DBS) power package and is pin
compatible with the TDA8944J.
2. Features
■
■
■
■
■
■
■
■
■
■
Gain/volume adjustment via a DC control pin
Soft clipping
Operating at a low supply voltage
Standby and mute mode
No on/off switching plops
Low standby current
High supply voltage ripple rejection
Outputs short-circuit protected to ground, supply and across the load
Thermally protected
Printed-circuit board compatible with TDA8946AJ and TDA8580J.
3. Applications
■ Mains fed applications (e.g. TV sound)
■ PC audio
■ Portable audio.
4. Quick reference data
Table 1:
Quick reference data
Symbol Parameter
Conditions
Min
Typ
Max
Unit
4.5
12
18
V
-
40
50
mA
VCC
supply voltage
Iq
quiescent supply current
Istb
standby supply current
-
-
10
µA
Po
output power
THD = 10%; RL = 8 Ω;
VCC = 12 V
6
7
-
W
THD
total harmonic distortion
Po = 1 W
-
0.07
0.5
%
VCC = 12 V; RL = ∞
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
Table 1:
Quick reference data…continued
Symbol Parameter
Min
Typ
Max
Unit
Gv(max)
maximum voltage gain
Conditions
29
30
31
dB
Gv(cr)
voltage gain control range
-
80
-
dB
SVRR
supply voltage ripple
rejection
-
55
-
dB
5. Ordering information
Table 2:
Ordering information
Type number
TDA8944AJ
Package
Name
Description
Version
DBS17P
plastic DIL-bent-SIL power package; 17 leads (lead SOT243-1
length 12 mm)
6. Block diagram
idth
VCC1
VCC2
3
16
1
IN1−
8
IN1+
6
GC
4
13
IN2−
9
IN2+
12
OUT1−
OUT1+
TDA8944AJ
14
OUT2−
17
OUT2+
VCC
MODE
SVR
10
STANDBY/
MUTE LOGIC
20
kΩ
SHORT CIRCUIT
AND
TEMPERATURE
PROTECTION
11
20
kΩ
7
2
15
MGW587
SGND
GND1
GND2
Fig 1. Block diagram.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
2 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
7. Pinning information
7.1 Pinning
handbook, halfpage
OUT1−
1
GND1
2
VCC1
3
OUT1+
4
n.c.
5
IN1+
6
SGND
7
IN1−
8
IN2−
9
TDA8944AJ
MODE 10
SVR 11
IN2+ 12
GC 13
OUT2− 14
GND2 15
VCC2 16
OUT2+ 17
MGW588
Fig 2. Pin configuration.
7.2 Pin description
Table 3:
Pin description
Symbol
Pin
Description
OUT1−
1
negative loudspeaker terminal 1
GND1
2
ground channel 1
VCC1
3
supply voltage channel 1
OUT1+
4
positive loudspeaker terminal 1
n.c.
5
not connected
IN1+
6
positive input 1
SGND
7
signal ground
IN1−
8
negative input 1
IN2−
9
negative input 2
MODE
10
mode selection input (standby, mute, operating)
SVR
11
half supply voltage decoupling (ripple rejection)
IN2+
12
positive input 2
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
3 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
Table 3:
Pin description…continued
Symbol
Pin
Description
GC
13
DC gain control
OUT2−
14
negative loudspeaker terminal 2
GND2
15
ground channel 2
VCC2
16
supply voltage channel 2
OUT2+
17
positive loudspeaker terminal 2
8. Functional description
The TDA8944AJ is a stereo BTL audio power amplifier capable of delivering 2 × 7 W
output power to an 8 Ω load at THD = 10%, using a 12 V power supply and an
external heatsink. The gain of both amplifiers can be adjusted through a DC control
voltage (pin GC). This feature can be used for volume control or a preset gain.
With the three-level MODE input the device can be switched from ‘standby’ to ‘mute’
and to ‘operating’ mode.
The TDA8944AJ outputs are protected by an internal thermal shutdown protection
mechanism and a short-circuit protection.
8.1 Input configuration
The TDA8944AJ inputs can be driven symmetrical (floating) as well as asymmetrical.
In the asymmetrical mode one input pin is connected via a capacitor to the signal
source and the other input is connected to the signal ground. This signal ground
should be as close as possible to the SVR (electrolytic) capacitor ground. Note that
the DC level of the input pins is half of the supply voltage VCC, so coupling capacitors
for both pins are necessary.
VCC
handbook, halfpage
IN +
IN −
signal
source
SVR
signal
ground
power
ground
MGW589
Fig 3. Asymmetrical input configuration.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
4 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
The input cut-off frequency is:
1
f i ( cut – off ) = -----------------------------------------2π ( 0.5 × R i × C i )
(1)
For Ri = 32 kΩ and Ci = 220 nF:
1
f i ( cut – off ) = -----------------------------------------------------------------------------= 45.2 Hz
3
–9
2π ( 0.5 × 32 × 10 × 220 × 10 )
(2)
As shown in Equation 2, large capacitors values for the inputs are not necessary; so
the switch-on delay during charging of the input capacitors can be minimized. This
results in a good low frequency response and good switch-on behaviour.
Remark: To prevent high frequency oscillations do not leave the inputs open, connect
a capacitor of 4.7 nF across the input pins close to the device (see Figure 15).
8.2 Power amplifier
The power amplifier is a Bridge-Tied Load (BTL) amplifier with an all-NPN output
stage, capable of delivering a peak output current of 2 A.
The BTL principle offers the following advantages:
•
•
•
•
8.2.1
Lower peak value of the supply current
The ripple frequency on the supply voltage is twice the signal frequency
No expensive DC-blocking capacitor
Good low frequency performance.
Output power measurement
The output power as a function of the supply voltage is measured on the output pins
at THD = 10%; see Figure 10. The maximum output power is limited by the supply
voltage of 12 V and the maximum available output current: 2 A repetitive peak
current.
8.2.2
Headroom
Typical CD music requires at least 12 dB (factor 15.85) dynamic headroom compared to the average power output - for transferring the loudest parts without
distortion. At VCC = 12 V, RL = 8 Ω and Po = 4 W at THD = 0.2% (see Figure 8), the
Average Listening Level (ALL) - music power - without any distortion yields:
4W
P o ( ALL ) = ------------- = 252.4 mW
15.85
(3)
The power dissipation can be derived from Figure 12 on page 11 for 0 dB
respectively 12 dB headroom.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
5 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
Table 4:
Power rating as function of headroom
Headroom
Power output (THD = 0.2%)
Power dissipation
0 dB
Po = 4 W
P = 7.8 W
12 dB
Po(ALL) = 252.4 mW
P = 4.0 W
For the average listening level a power dissipation of 4 W can be used for a heatsink
calculation.
8.3 Mode selection
The TDA8944AJ has three functional modes, which can be selected by applying the
proper DC voltage to pin MODE.
Standby — In this mode the current consumption is very low and the outputs are
floating. The device is in standby mode when VMODE > (VCC − 0.5 V), or when the
MODE pin is left floating.
Mute — In this mode the amplifier is DC-biased but not operational (no audio output).
This allows the input coupling capacitors to be charged to avoid pop-noise. The
device is in mute mode when 3.5 V < VMODE < (VCC − 1.5 V).
Operating — In this mode the amplifier is operating normally. The operating mode is
activated at VMODE < 1.0 V.
8.3.1
Switch-on and switch-off
To avoid audible plops during supply voltage switch-on or switch-off, the device is set
to standby mode before the supply voltage is applied (switch-on) or removed
(switch-off).
The switch-on and switch-off time can be influenced by an RC-circuit on the MODE
pin. Rapid on/off switching of the device or the rapid switching of the MODE pin may
cause ‘click-and pop-noise’. This can be prevented by proper timing of the RC-circuit
on the MODE pin.
8.4 DC gain control
The gain of both amplifiers can be adjusted (logarithmic) by applying an external DC
voltage source on pin GC (see Figure 6). The DC voltage source range is
0.5 to 4.0 V. This feature can be used for volume control or a preset gain.
The maximum voltage gain is set at +30 dB and the control range is more than 80 dB,
so the minimal gain is less than −50 dB. When pin GC is not connected, the gain is
set at +24 dB.
8.5 Supply Voltage Ripple Rejection (SVRR)
The SVRR is measured with an electrolytic capacitor of 10 µF on pin SVR at a
bandwidth of 10 Hz to 80 kHz. Figure 14 illustrates the SVRR as function of the
frequency. A larger capacitor value on the SVR pin improves the ripple rejection
behavior at the lower frequencies.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
6 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
8.6 Built-in protection circuits
The TDA8944AJ contains two types of protection circuits, i.e. short-circuit and
thermal shutdown.
8.6.1
Short-circuit protection
Short-circuit to ground or supply line — This is detected by a so-called ‘missing
current’ detection circuit which measures the current in the positive supply line and
the current in the ground line. A difference between both currents larger than 0.8 A,
switches the power stage to the standby mode; high impedance of the outputs and
very low supply current.
Short-circuit across the load — This is detected by an absolute-current
measurement. An absolute-current larger than 2 A, switches the power stage to
standby mode; high impedance of the outputs and a very low supply current.
8.6.2
Thermal shutdown protection
The junction temperature is measured by a temperature sensor; at a junction
temperature of approximately 150 °C this detection circuit switches the power stage
to the standby mode; high impedance of the outputs and very low supply current.
9. Limiting values
Table 5:
Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol
Parameter
Conditions
Min
Max
Unit
VCC
supply voltage
no signal
−0.3
+25
V
operating
−0.3
+18
V
VI
input voltage
−0.3
VCC + 0.3
V
IORM
repetitive peak output current
-
2
A
Tstg
storage temperature
−55
+150
°C
Tamb
operating ambient temperature
−40
+85
°C
Ptot
total power dissipation
-
18
W
VCC(sc)
supply voltage to guarantee short-circuit
protection
-
15
V
non-operating
10. Thermal characteristics
Table 6:
Thermal characteristics
Symbol
Parameter
Conditions
Value
Unit
Rth(j-a)
thermal resistance from junction to ambient
in free air
40
K/W
Rth(j-mb)
thermal resistance from junction to mounting base both channels driven
4.5
K/W
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
7 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
11. Static characteristics
Table 7:
Static characteristics
VCC = 12 V; Tamb = 25 °C; RL = 8 Ω; VMODE = 0 V; Vi = 0 V; measured in test circuit Figure 15; unless otherwise specified.
Symbol
Parameter
Conditions
VCC
supply voltage
operating
Iq
quiescent supply current
RL = ∞
Istb
standby supply current
VMODE = VCC
VO
DC output voltage
∆VOUT[3]
differential output voltage
offset
VMODE
mode selection input voltage operating mode
[1]
[2]
Min
Typ
Max
Unit
4.5
12
18
V
-
40
50
mA
-
-
10
µA
-
6
-
V
-
-
170
mV
0
-
1.0
V
mute mode
3.5
-
VCC − 1.5
V
standby mode
VCC − 0.5
-
VCC
V
-
-
20
µA
IMODE
mode selection input current 0 < VMODE < VCC
VGC
gain control voltage (pin GC) pin GC not connected
-
2.75
-
V
IGC
current into pin GC
-
600
-
µA
[1]
[2]
[3]
VGC = 0 V
With a load connected at the outputs the quiescent current will increase, the maximum of this increase being equal to the differential
output voltage offset (∆VOUT) divided by the load resistance (RL).
The DC output voltage with respect to ground is approximately 0.5VCC.
∆VOUT = VOUT+ − VOUT− .
MGW590
50
MGW591
50
handbook, halfpage
handbook, halfpage
Iq
(mA)
Iq
(mA)
40
40
30
30
20
20
10
10
0
0
0
4
8
12
16
20
VCC (V)
0
4
8
12
16
20
VMODE (V)
VCC = 12 V
Fig 4. Quiescent current as function of supply
voltage.
Fig 5. Quiescent current as function of mode voltage.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
8 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
12. Dynamic characteristics
Table 8:
Dynamic characteristics
VCC = 12 V; Tamb = 25 °C; RL = 8 Ω; f = 1 kHz; VMODE = 0 V; Gv = 30 dB; VGC = 4.0 V; measured in test circuit Figure 15;
unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
Po
output power
THD = 10%
6
7
-
W
THD
total harmonic distortion
Gv(max)
maximum voltage gain
Gv(cr)
gain control range
Vi(rms)
input voltage (RMS value)
Zi(dif)
differential input impedance
noise output voltage
Vn(o)
SVRR
supply voltage ripple rejection
THD = 0.5%
-
5
-
W
Po = 1 W
-
0.07
0.5
%
29
30
31
dB
0.5 < VGC < 4.0 V
-
80
-
dB
Gv = 0 dB; THD <1%
1.0
-
-
V
50
65
-
kΩ
VGC = 4.0 V
[1]
-
120
150
µV
VGC = 1.0 V
[1]
-
30
-
µV
fripple = 1 kHz
[2]
-
55
-
dB
fripple = 100 Hz to 20 kHz
[2]
-
55
-
dB
[3]
-
30
50
µV
Vo(mute)
output voltage
mute mode
αcs
channel separation
Rsource = 0 Ω
50
75
-
dB
|∆Gv|
channel unbalance
Gv = 0 dB; VGC = 1.8 V
-
-
1
dB
[1]
[2]
[3]
The noise output voltage is measured at the output in a frequency range from 20 Hz to 20 kHz (unweighted), with a source impedance
Rsource = 0 Ω at the input.
Supply voltage ripple rejection is measured at the output, with a source impedance Rsource = 0 Ω at the input. The ripple voltage is a sine
wave with a frequency fripple and an amplitude of 700 mV (RMS), which is applied to the positive supply rail.
Output voltage in mute mode is measured with VGC = 0 V and an input voltage of 1 V (RMS) in a bandwidth of 20 kHz, thus including
noise.
MGW592
40
v
(dB)
20
handbook, halfpage
Vo
(V)
1
0
10−1
−20
10−2
−40
10−3
−60
10−4
−80
MGW593
10
handbook,
G halfpage
0
1
2
3
4
VGC (V)
VCC = 12 V
10−5
0
8
VMODE (V)
12
Vi = 30 mV; VCC = 12 V
Fig 6. Voltage gain as function of control voltage.
Fig 7. Output voltage as function of mode voltage.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
4
Rev. 01 — 01 March 2002
9 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
MGW594
102
handbook, halfpage
MGW595
10
handbook, halfpage
THD
(%)
THD
(%)
10
1
(1)
1
(2)
10−1
10−1
10−2
10−2
10−1
1
10
Po (W)
102
VCC = 12 V
10−2
102
10
103
104
f (Hz)
105
VCC = 12 V; no bandpass filter applied
(1) Po = 0.1 W
(2) Po = 1 W
Fig 8. Total harmonic distortion as function of output
power.
MGW596
16
handbook, halfpage
Fig 9. Total harmonic distortion as function of
frequency.
MGW597
20
handbook, halfpage
Ptot
Po
(W)
(W)
(1)
16
12
(2)
12
8
8
4
4
0
0
0
4
8
12
16
20
VCC (V)
RL = 8 Ω
0
4
8
12
16
20
VCC (V)
RL = 8 Ω
(1) THD = 10%
(2) THD = 1%
Fig 10. Output power as function of supply voltage.
Fig 11. Total power dissipation (worst-case) as
function of supply voltage.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
10 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
MGW598
MGW599
0
10
P
(W)
handbook, halfpage
αcs
(dB)
handbook, halfpage
8
−20
6
−40
4
−60
2
−80
−100
0
0
2
4
6
8
Po (W)
102
10
10
VCC = 12 V; RL = 8 Ω
103
104
f (Hz)
105
VCC = 12 V; no bandpass filter applied
Fig 12. Power dissipation as function of output power.
Fig 13. Channel separation as function of frequency.
MGW600
0
handbook, halfpage
SVRR
(Hz)
−20
−40
B
A
−60
−80
−100
10
102
103
104
f (Hz)
105
VCC = 12 V; Rsource = 0 Ω; Vripple = 707 mV (RMS); a bandpass filter of 10 Hz to 80 kHz has been applied.
Curve A: inputs short-circuited
Curve B: inputs short-circuited and connected to ground.
Fig 14. Supply voltage ripple rejection as function of frequency.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
11 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
13. Internal circuitry
Table 9:
Internal circuitry
Pin
Symbol
6 and 8
IN1+ and IN1−
12 and 9
IN2+ and IN2−
Equivalent circuit
VCC
handbook, halfpage
VCC
3 kΩ
3 kΩ
32 kΩ
32 kΩ
VCC
8, 9
6, 12
1/2 VCC
(SVR)
1 and 4
OUT1− and OUT1+
14 and 17
OUT2− and OUT2+
MGW601
VCC
handbook, halfpage
600 Ω
1, 4, 14, 17
100 Ω
1/2 VCC
MGW602
10
MODE
handbook, halfpage
VCC
VCC
1 kΩ
VCC
1 kΩ
10
OFF
HIGH
MUTE
HIGH
MGW603
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
12 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
Table 9:
Internal circuitry…continued
Pin
Symbol
11
SVR
Equivalent circuit
VCC
handbook, halfpage
Standby
VCC
17.6 kΩ
11
17.6 kΩ
MGW604
13
GC
handbook, halfpage
VCC
1:1
13
5.65 kΩ
2.5 kΩ
736 Ω
2.75 V
MGW605
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
13 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
14. Application information
VCC
handbook, full pagewidth
Rsource
220 nF
Vi
VCC1
VCC2
3
16
100 nF
IN1− 8
1
OUT1−
4.7
nF
220 nF (1)
1000 µF
RL
8Ω
IN1+ 6
4
220 nF
4Ω
OUT1+
4Ω
220 nF
GC 13
or
Rsource
220 nF
Vi
TDA8944AJ
IN2− 9
14
OUT2−
4.7
nF
RL
220 nF (1) IN2+ 12
17
OUT2+
MODE 10
STANDBY/
MUTE LOGIC
20
kΩ
4Ω
SHORT CIRCUIT
AND
TEMPERATURE
PROTECTION
SVR 11
20
kΩ
10 µF
4Ω
220 nF
VCC
MICROCONTROLLER
8Ω
220 nF
7
2
15
SGND
GND1
GND2
MGW606
(1) To prevent high frequency oscillations do not leave the inputs open, connect a capacitor of 4.7 nF across the input pins
close to the device.
Fig 15. Application diagram.
14.1 Printed-circuit board
14.1.1
Layout and grounding
For a high system performance level certain grounding techniques are essential.
The input reference grounds have to be tied with their respective source grounds and
must have separate tracks from the power ground tracks; this will prevent the large
(output) signal currents from interfering with the small AC input signals. The
small-signal ground tracks should be physically located as far as possible from the
power ground tracks. Supply and output tracks should be as wide as possible for
delivering maximum output power.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
14 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
4Ω
OUT2−
ON
220 nF
4Ω
OUT2+
220
nF
MODE
SVR
10 µF
1
220 nF
IN2+
GC
IN2−
4.7
nF
SGND
IN1−
4.7
nF
220 nF
220 nF
100 nF
1
OUT1−
220 nF
IN1+
4Ω
1000 µF
VCC
OUT1+
4Ω
GND
MGW607
Fig 16. Printed-circuit board layout (single-sided); components view.
14.1.2
Power supply decoupling
Proper supply bypassing is critical for low-noise performance and high supply voltage
ripple rejection. The respective capacitor location should be as close as possible to
the device and grounded to the power ground. Proper power supply decoupling also
prevents oscillations.
For suppressing higher frequency transients (spikes) on the supply line a capacitor
with low ESR - typical 100 nF - has to be placed as close as possible to the device.
For suppressing lower frequency noise and ripple signals, a large electrolytic
capacitor - e.g. 1000 µF or greater - must be placed close to the device.
The bypass capacitor on the SVR pin reduces the noise and ripple on the midrail
voltage. For good THD and noise performance a low ESR capacitor is recommended.
14.2 Thermal behaviour and heatsink calculation
The measured maximum thermal resistance of the IC package, Rth(j-mb) is 4.5 K/W.
A calculation for the heatsink can be made, with the following parameters:
Tamb = 50 °C
VCC = 12 V and RL = 8 Ω
Tj(max) = 150 °C
Rth(tot) is the total thermal resistance between the junction and the ambient
including the heatsink. In the heatsink calculations the value of Rth(mb-h) is ignored.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
15 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
At VCC = 12 V and RL = 8 Ω the measured worst-case sine-wave dissipation is 8 W;
see Figure 12. For Tj(max) = 150 °C the temperature rise - caused by the power
dissipation - is: 150 − 50 = 100 °C.
P × Rth(tot) = 100 °C
Rth(tot) = 100/8 = 12.5 K/W
Rth(h-a) = Rth(tot) − Rth(j-mb) = 12.5 − 4.5 = 8.0 K/W.
The calculation above is for an application at worst-case (stereo) sine-wave output
signals. In practice music signals will be applied, which decreases the maximum
power dissipation to approximately half of the sine-wave power dissipation (see
Section 8.2.2). This allows for the use of a smaller heatsink:
P × Rth(tot) = 100 °C
Rth(tot) = 100/(0.5 × 8) = 25 K/W
Rth(h-a) = Rth(tot) − Rth(j-mb) = 25 − 4.5 = 20.5 K/W.
To increase the lifetime of the IC, Tj(max) should be reduced to 125 °C. This requires a
heatsink of approximately 14 K/W for music signals.
15. Test information
15.1 Quality information
The “General Quality Specification for Integrated Circuits, SNW-FQ-611D” is
applicable (ordering code 9397 750 05459).
15.1.1
Test conditions
Tamb = 25 °C; VCC = 12 V; f = 1 kHz; RL = 8 Ω; audio pass band 22 Hz to 22 kHz;
unless otherwise specified.
Remark: In the graphs as function of frequency no bandpass filter was applied;
see Figure 9 and 13.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
16 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
16. Package outline
DBS17P: plastic DIL-bent-SIL power package; 17 leads (lead length 12 mm)
SOT243-1
non-concave
Dh
x
D
Eh
view B: mounting base side
d
A2
B
j
E
A
L3
L
Q
c
1
v M
17
e1
Z
bp
e
e2
m
w M
0
5
10 mm
scale
DIMENSIONS (mm are the original dimensions)
UNIT
A
A2
bp
c
D (1)
d
Dh
E (1)
e
mm
17.0
15.5
4.6
4.4
0.75
0.60
0.48
0.38
24.0
23.6
20.0
19.6
10
12.2
11.8
2.54
e1
e2
1.27 5.08
Eh
j
L
L3
m
Q
v
w
x
Z (1)
6
3.4
3.1
12.4
11.0
2.4
1.6
4.3
2.1
1.8
0.8
0.4
0.03
2.00
1.45
Note
1. Plastic or metal protrusions of 0.25 mm maximum per side are not included.
OUTLINE
VERSION
REFERENCES
IEC
JEDEC
EIAJ
EUROPEAN
PROJECTION
ISSUE DATE
97-12-16
99-12-17
SOT243-1
Fig 17. DBS17P package outline.
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
17 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
17. Soldering
17.1 Introduction to soldering through-hole mount packages
This text gives a brief insight to wave, dip and manual soldering. A more in-depth
account of soldering ICs can be found in our Data Handbook IC26; Integrated Circuit
Packages (document order number 9398 652 90011).
Wave soldering is the preferred method for mounting of through-hole mount IC
packages on a printed-circuit board.
17.2 Soldering by dipping or by solder wave
The maximum permissible temperature of the solder is 260 °C; solder at this
temperature must not be in contact with the joints for more than 5 seconds. The total
contact time of successive solder waves must not exceed 5 seconds.
The device may be mounted up to the seating plane, but the temperature of the
plastic body must not exceed the specified maximum storage temperature (Tstg(max)).
If the printed-circuit board has been pre-heated, forced cooling may be necessary
immediately after soldering to keep the temperature within the permissible limit.
17.3 Manual soldering
Apply the soldering iron (24 V or less) to the lead(s) of the package, either below the
seating plane or not more than 2 mm above it. If the temperature of the soldering iron
bit is less than 300 °C it may remain in contact for up to 10 seconds. If the bit
temperature is between 300 and 400 °C, contact may be up to 5 seconds.
17.4 Package related soldering information
Table 10:
Suitability of through-hole mount IC packages for dipping and wave
soldering methods
Package
Soldering method
DBS, DIP, HDIP, SDIP, SIL
[1]
Dipping
Wave
suitable
suitable[1]
For SDIP packages, the longitudinal axis must be parallel to the transport direction of the
printed-circuit board.
18. Revision history
Table 11:
Revision history
Rev Date
01
20020301
CPCN
Description
-
Product data (9397 750 09433)
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Product data
Rev. 01 — 01 March 2002
18 of 20
TDA8944AJ
Philips Semiconductors
2 x 7 W BTL audio amplifier with DC gain control
19. Data sheet status
Data sheet status[1]
Product status[2]
Definition
Objective data
Development
This data sheet contains data from the objective specification for product development. Philips Semiconductors
reserves the right to change the specification in any manner without notice.
Preliminary data
Qualification
This data sheet contains data from the preliminary specification. Supplementary data will be published at a
later date. Philips Semiconductors reserves the right to change the specification without notice, in order to
improve the design and supply the best possible product.
Product data
Production
This data sheet contains data from the product specification. Philips Semiconductors reserves the right to
make changes at any time in order to improve the design, manufacturing and supply. Changes will be
communicated according to the Customer Product/Process Change Notification (CPCN) procedure
SNW-SQ-650A.
[1]
Please consult the most recently issued data sheet before initiating or completing a design.
[2]
The product status of the device(s) described in this data sheet may have changed since this data sheet was published. The latest information is available on the Internet at
URL http://www.semiconductors.philips.com.
20. Definitions
21. Disclaimers
Short-form specification — The data in a short-form specification is
extracted from a full data sheet with the same type number and title. For
detailed information see the relevant data sheet or data handbook.
Life support — These products are not designed for use in life support
appliances, devices, or systems where malfunction of these products can
reasonably be expected to result in personal injury. Philips Semiconductors
customers using or selling these products for use in such applications do so
at their own risk and agree to fully indemnify Philips Semiconductors for any
damages resulting from such application.
Limiting values definition — Limiting values given are in accordance with
the Absolute Maximum Rating System (IEC 60134). Stress above one or
more of the limiting values may cause permanent damage to the device.
These are stress ratings only and operation of the device at these or at any
other conditions above those given in the Characteristics sections of the
specification is not implied. Exposure to limiting values for extended periods
may affect device reliability.
Application information — Applications that are described herein for any
of these products are for illustrative purposes only. Philips Semiconductors
make no representation or warranty that such applications will be suitable for
the specified use without further testing or modification.
Right to make changes — Philips Semiconductors reserves the right to
make changes, without notice, in the products, including circuits, standard
cells, and/or software, described or contained herein in order to improve
design and/or performance. Philips Semiconductors assumes no
responsibility or liability for the use of any of these products, conveys no
licence or title under any patent, copyright, or mask work right to these
products, and makes no representations or warranties that these products are
free from patent, copyright, or mask work right infringement, unless otherwise
specified.
Contact information
For additional information, please visit http://www.semiconductors.philips.com.
For sales office addresses, send e-mail to: [email protected].
Product data
Fax: +31 40 27 24825
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
9397 750 09433
Rev. 01 — 01 March 2002
19 of 20
Philips Semiconductors
TDA8944AJ
2 x 7 W BTL audio amplifier with DC gain control
Contents
1
2
3
4
5
6
7
7.1
7.2
8
8.1
8.2
8.2.1
8.2.2
8.3
8.3.1
8.4
8.5
8.6
8.6.1
8.6.2
9
10
11
12
13
14
14.1
14.1.1
14.1.2
14.2
15
15.1
15.1.1
16
17
17.1
17.2
17.3
17.4
18
19
20
21
General description . . . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Quick reference data . . . . . . . . . . . . . . . . . . . . . 1
Ordering information . . . . . . . . . . . . . . . . . . . . . 2
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Pinning information . . . . . . . . . . . . . . . . . . . . . . 3
Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 3
Functional description . . . . . . . . . . . . . . . . . . . 4
Input configuration . . . . . . . . . . . . . . . . . . . . . . 4
Power amplifier . . . . . . . . . . . . . . . . . . . . . . . . . 5
Output power measurement . . . . . . . . . . . . . . . 5
Headroom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Mode selection . . . . . . . . . . . . . . . . . . . . . . . . . 6
Switch-on and switch-off. . . . . . . . . . . . . . . . . . 6
DC gain control . . . . . . . . . . . . . . . . . . . . . . . . . 6
Supply Voltage Ripple Rejection (SVRR) . . . . . 6
Built-in protection circuits . . . . . . . . . . . . . . . . . 7
Short-circuit protection . . . . . . . . . . . . . . . . . . . 7
Thermal shutdown protection . . . . . . . . . . . . . . 7
Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . . 7
Thermal characteristics. . . . . . . . . . . . . . . . . . . 7
Static characteristics. . . . . . . . . . . . . . . . . . . . . 8
Dynamic characteristics . . . . . . . . . . . . . . . . . . 9
Internal circuitry. . . . . . . . . . . . . . . . . . . . . . . . 12
Application information. . . . . . . . . . . . . . . . . . 14
Printed-circuit board . . . . . . . . . . . . . . . . . . . . 14
Layout and grounding . . . . . . . . . . . . . . . . . . . 14
Power supply decoupling . . . . . . . . . . . . . . . . 15
Thermal behaviour and heatsink calculation . 15
Test information . . . . . . . . . . . . . . . . . . . . . . . . 16
Quality information . . . . . . . . . . . . . . . . . . . . . 16
Test conditions . . . . . . . . . . . . . . . . . . . . . . . . 16
Package outline . . . . . . . . . . . . . . . . . . . . . . . . 17
Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Introduction to soldering through-hole
mount packages . . . . . . . . . . . . . . . . . . . . . . 18
Soldering by dipping or by solder wave . . . . . 18
Manual soldering . . . . . . . . . . . . . . . . . . . . . . 18
Package related soldering information . . . . . . 18
Revision history . . . . . . . . . . . . . . . . . . . . . . . . 18
Data sheet status . . . . . . . . . . . . . . . . . . . . . . . 19
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
© Koninklijke Philips Electronics N.V. 2002.
Printed in The Netherlands
All rights are reserved. Reproduction in whole or in part is prohibited without the prior
written consent of the copyright owner.
The information presented in this document does not form part of any quotation or
contract, is believed to be accurate and reliable and may be changed without notice. No
liability will be accepted by the publisher for any consequence of its use. Publication
thereof does not convey nor imply any license under patent- or other industrial or
intellectual property rights.
Date of release: 01 March 2002
Document order number: 9397 750 09433