AN10436 PHILIPS [NXP Semiconductors], AN10436 Datasheet - Page 30

• Manufacturer Part Number: AN10436
• Description: TDA8932B/33(B) Class-D audio amplifier
• Manufacturer: PHILIPS [NXP Semiconductors]

NXP Semiconductors
AN10436_1
Application note
This zobel damping network is quite effective for a voice coil inductance L
zobel damping network will lower the resonance peak current in the filter inductor by at
least 15 % to 40 % lowering the risk of unwanted inductor saturation.
Remark: Besides inductor saturation a tweeter might also benefit from a zobel network
since filter resonance can overstress the tweeter.
Table 6
Table 6.
A minimum zobel damping network C
The optimum damping resistors are equal for 6 Ω and 8 Ω speakers when using the filter
component values from
The resistor (R
with a 20 kHz unclipped sine wave.
Figure 27
Configuration
Single ended
Fig 27. Power dissipation as a function of supply voltage
(1) C
(2) C
(3) C
(4) C
(5) C
contains the optimum damping resistors for different capacitor values:
Z
Z
Z
Z
Z
shows the sine wave power dissipation (20 kHz) as a function of supply voltage.
Damping resistors for different capacitor values
= 47 nF / R
= 68 nF / R
= 100 nF / R
= 150 nF / R
= 220 nF / R
(W)
P
Z
2.5
1.5
0.5
) should be able to at least dissipate the power when driving the amplifier
2
1
0
10
Speaker
impedance (Ω)
-
-
4
-
-
Z
Z
Rev. 01 — 12 December 2007
Z
Z
Z
= 82 Ω
= 56 Ω
= 39 Ω
= 27 Ω
= 22 Ω
Table
4, which are calculated based on f
18
L
-
-
22
-
-
Z
LC
= 47 nF and R
(μH)
TDA8932B/33(B) Class-D audio amplifier
C
-
-
680
-
-
26
LC
(nF)
Z
= 82 Ω is strongly recommended.
C
47
68
100
150
220
Z
010aaa427
V
o
(nF)
P
= 40 kHz.
(5)
(4)
(3)
(2)
(1)
(V)
36
AN10436
© NXP B.V. 2007. All rights reserved.
E
< 10 L
R
82
56
39
27
22
Z
(Ω)
LC
30 of 55
. The