sta335bwqs STMicroelectronics, sta335bwqs Datasheet - Page 66

• Manufacturer Part Number: sta335bwqs
• Description: 2.1-channel High-efficiency Digital Audio System With Qsound Qhd?
• Manufacturer: STMicroelectronics

Package thermal characteristics
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Package thermal characteristics
Using a double-layer PCB the thermal resistance (junction to ambient) with 2 copper ground
areas of 3 cm x 3 cm and with 16 via holes (see
convection.
The dissipated power within the device depends primarily on the supply voltage, load
impedance and output modulation level.
The max estimated dissipated power for the STA335BWQS is:
2 x 20 W @ 8 Ω, 18 V
2 x 10 W + 1 x 20 W @ 4 Ω, 8 Ω, 18 V
2 x 15 W @ 16 Ω, 24 V
Figure 24. Double-layer PCB with copper ground area and 16 vias
Figure 25
two different sizes of copper layers.
Figure 25. PowerSSO-36 power derating curves
shows the power derating curves for the PowerSSO-36 package on a board with
Pd (W)
8
8
7
7
6
6
5
5
4
4
3
3
2
2
1
1
0
0
0
0
Copper Area 2x2 cm
and via holes
20
20
40
40
Copper Area 3x3 cm
and via holes
Pd max ~ 4 W
Pd max < 5 W
Pd max ~ 3 W
60
60
Tamb ( °C)
Figure
80
80
100
100
24) is 24 °C/W in natural air
STA335BWQS
PowerSSO-36
120
120
STA335BW
PSSO36
140
140
160
160
STA335BWQS