TDA8922CTH/N1,118 NXP Semiconductors, TDA8922CTH/N1,118 Datasheet - Page 20

• Manufacturer Part Number: TDA8922CTH/N1,118
• Description: IC AMP AUDIO CLASS D 24HSOP
• Manufacturer: NXP Semiconductors
• Type: Class Dr

Specifications of TDA8922CTH/N1,118

• Output Type: 1-Channel (Mono) or 2-Channel (Stereo)
• Max Output Power X Channels @ Load: 155W x 1 @ 8 Ohm; 75W x 2 @ 6 Ohm
• Voltage - Supply: ±12.5 V ~ 32.5 V
• Features: Depop, Differential Inputs, Mute, Short-Circuit and Thermal Protection, Standby
• Mounting Type: Surface Mount
• Package / Case: 24-HSOP
• Operational Class: Class-D
• Audio Amplifier Function: Speaker
• Total Harmonic Distortion: 0.02@8Ohm@1W%
• Single Supply Voltage (typ): Not RequiredV
• Power Supply Requirement: Dual
• Rail/rail I/o Type: No
• Single Supply Voltage (min): Not RequiredV
• Single Supply Voltage (max): Not RequiredV
• Dual Supply Voltage (min): ±12.5V
• Mounting: Surface Mount
• Pin Count: 24
• Package Type: HSOP
• Lead Free Status / RoHS Status: Lead free by exemption / RoHS compliant by exemption
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free by exemption / RoHS compliant by exemption
• Other names: 935286885118

NXP Semiconductors
TDA8922C_1
Product data sheet
13.6 Pumping effects
In the following example, a heatsink calculation is made for an 8
When the maximum expected ambient temperature is 50 C, the total R
R
So the thermal resistance between heatsink and ambient temperature is:
The derating curves for power dissipation (for several R
Figure
maximum allowable power dissipation for a given heatsink size can be derived, or the
required heatsink size can be determined, at a required power dissipation level; see
Figure
In a typical stereo single-ended configuration, the TDA8922C is supplied by a symmetrical
supply voltage (e.g. V
configuration, a ‘pumping effect’ can occur. During one switching interval, energy is taken
from one supply (e.g. V
(e.g. V
across the output capacitors of that voltage supply source increases and the supply
voltage is pumped to higher levels. The voltage increase caused by the pumping effect
depends on:
Pumping effects should be minimized to prevent the malfunctioning of the audio amplifier
and/or the voltage supply source. Amplifier malfunction due to the pumping effect can
trigger UVP, OVP or UBP.
-------------------------
30 V supply:
150 50
•
•
•
•
•
th(j-a)
The audio signal has a crest factor of 10 (the ratio between peak power and average
power (20 dB)); this means that the average output power is
Thus, the peak RMS output power level is the 0.5 % THD level, i.e. 110 W.
The average power is then
The dissipated power at an output power of 11 W is approximately 5 W.
R
R
mounting)
R
th(j-c)
th(c-h)
th(h-a)
Speaker impedance
Supply voltage
Audio signal frequency
Value of supply line decoupling capacitors
Source and sink currents of other channels
5
–
SS
= R
9. A maximum junction temperature T
9.
(thermal resistance from junction to case) = 1.5 K/W
) and vice versa. When the voltage supply source cannot sink energy, the voltage
(thermal resistance from case to heatsink) = 0.5 K/W to 1 K/W (dependent on
(thermal resistance from heatsink to ambient) = 20
th(j-c)
=
20 K/W
+ R
th(c-h)
Rev. 01 — 7 September 2009
DD
DD
+ R
= 30 V and V
), while a part of that energy is returned to the other supply line
th(h-a)
1
10
110 W = 11 W.
SS
= 30 V). When the amplifier is used in an SE
j
= 150 C is taken into account. The
2
th(j-a)
75 W class-D power amplifier
values) are illustrated in
(1.5 + 1) = 17.5 K/W
1
10
of the peak power.
BTL application with a
TDA8922C
© NXP B.V. 2009. All rights reserved.
th(j-a)
becomes
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