SA58631 Datasheet, PDF (7/21 Pages) NXP Semiconductors – 3 W BTL audio amplifier

NXP Semiconductors
13. Application information
SA58631
3 W BTL audio amplifier
C1
R1
1 µF _{11 kΩ}
VI
R2
56 kΩ
IN− ₄
IN+ ₃
SVR ₂
C2 MODE
47 µF
1
6
SA58631
100 nF
5 ^OUT−
RL
8 ^OUT+
7
GND
V_CC
100 µF
002aac007
Gain = 2 × -^RR----²¹-
Fig 3. Application diagram of SA58631 BTL differential output configuration
14. Test information
14.1 Test conditions
The junction to ambient thermal resistance, R_th(j-a) = 27.7 K/W for the HVSON8 package
when the exposed die attach paddle is soldered to 32 cm² (5 in²) area of 35 µm (1 ounce)
copper heat spreader on the demo PCB. The maximum sine wave power dissipation for
T_amb = 25 °C is:
1_----5_---0_----–_-----2_---5_{- = 4.5 W}
27.7
Thus, for T_amb = +85 °C the maximum total power dissipation is:
1_----5_--2-0_--7--–_-.-7---8_---5_{- = 2.35 W}
The power dissipation versus ambient temperature curve (Figure 5) shows the power
derating profiles with ambient temperature for three sizes of heat spreaders. For a more
modest heat spreader using 9.7 cm² (1.5 in²) area on the top side of the PCB, the
R_th(j-a) is 31.25 K/W. When the package is not soldered to a heat spreader, the R_th(j-a)
increases to 83.3 K/W.
SA58631_2
Product data sheet
Rev. 02 — 12 October 2007
© NXP B.V. 2007. All rights reserved.
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