tda8932t-n1 NXP Semiconductors, tda8932t-n1 Datasheet - Page 29

• Manufacturer Part Number: tda8932t-n1
• Description: Tda8932 Class-d Audio Amplifier
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TDA8932_2
Preliminary data sheet
14.8 Pumping effects
Example 2
In case of music output power at 25 % of the rated power, the T
The maximum junction temperature T
When the amplifier is used in a SE configuration, a so-called 'pumping effect' can occur.
During one switching interval, energy is taken from one supply (e.g. V
that energy is delivered back to the other supply line (e.g. V
the power supply cannot sink energy, the voltage across the output capacitors of that
power supply will increase.
The voltage increase caused by the pumping effect depends on:
The pumping effect should not cause a malfunction of either the audio amplifier and/or the
power supply. For instance, this malfunction can be caused by triggering of the
undervoltage or overvoltage protection of the amplifier.
Pumping effects in a SE configuration can be minimized by connecting audio inputs in
anti-phase and change the polarity of one speaker. This is illustrated in
Fig 12. SE application for reducing pumping effects
•
•
•
•
•
•
•
At V
P = 1.6 W at P
R
Speaker impedance
Supply voltage
Audio signal frequency
Value of decoupling capacitors on supply lines
Source and sink currents of other channels
th(j-a)
P
= 30 V and P
= 43 K/W
audio
audio
o
in1
in2
= 3.75 W (see
Rev. 02 — 12 December 2006
o
= 2
(0.25
IN1N
IN2N
IN1P
IN2P
Figure
j(max)
15) = 2
20)
= 25 + 1.6
3.75 W into 8 , the power dissipation
43 = 93.8 C.
OUT1
OUT2
SSP1
j(max)
) and visa versa. When
001aad763
Class-D audio amplifier
DDP1
is much lower.
TDA8932
© NXP B.V. 2006. All rights reserved.
Figure
), while a part of
12.
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