sta335bwsqs13tr STMicroelectronics, sta335bwsqs13tr Datasheet - Page 64

• Manufacturer Part Number: sta335bwsqs13tr
• Description: 2.1-channel, High-efficiency Digital Audio System With Qsound Qhd
• Manufacturer: STMicroelectronics

Package thermal characteristics
8
8.1
64/70
Package thermal characteristics
Using a double-layer PCB the thermal resistance (junction to ambient) with two copper
ground areas of 3 x 3 cm
convection.
The dissipated power within the device depends primarily on the supply voltage, load
impedance and output modulation level.
The estimated maximum dissipated power for the STA335BWSQS is:
2 x 20 W into 8 Ω at 18 V
2 x 10 W + 1 x 20 W into 4 Ω, 8 Ω at 18 V Pd max < 5 W
Figure 20. Double-layer PCB with copper ground area and 16 via holes
Figure 21
two different sizes of copper layers.
Figure 21. PowerSSO-36 power derating curves
Thermal data
Table 72.
R
T
th-sdj
th j-case
shows the power derating curves for the PowerSSO-36 package on a board with
Thermal resistance junction-case (thermal
pad)
Thermal shut-down junction temperature
Thermal data
Pd (W)
8
8
7
7
6
6
5
5
4
4
3
3
2
2
1
1
0
0
0
0
2
Copper Area 2x2 cm
and via holes
and with 16 via holes (see
20
20
Parameter
40
40
Copper Area 3x3 cm
and via holes
60
60
Pd max ~ 4 W
Tamb ( °C)
80
80
100
100
Figure
Min
120
120
STA335BW
PSSO36
STA335BWSQS
PowerSSO-36
20) is 24° C/W in natural air
150
140
140
Typ
160
160
1.5
STA335BWSQS
Max
°C/W
°C
Unit