TDA7496SSA Datasheet, PDF (9/12 Pages) STMicroelectronics – 5W+5W AMPLIFIER

Figure 17. PIN ST-BY
STBY
V_S
10µA
200
65K
D97AU594
Figure 18. PIN: MUTE
V_S
MUTE
200
10K
50µA
D97AU592
TDA7496SSA
Figure 19. PINS: OUT R, OUT L
V_S
OUT
D97AU588
Figure 20. PINS: PW-GND, S-GND
GND
V_S
D97AU593
HEAT SINK DIMENSIONING:
In order to avoid the thermal protection intervention, that is placed approximatively at T_j = 150°C, it is important
the dimensioning of the Heat Sinker R_Th (°C/W).
The parameters that influence the dimensioning are:
– Maximum dissipated power for the device (P_dmax)
– Max thermal resistance Junction to case (R_{Th j-c})
– Max. ambient temperature T_{amb max}
– Quiescent current I_q (mA)
Example:
V_CC = 22V, R_load = 8ohm, R_{Th j-c} = 5 °C/W , T_{amb max} = 50°C
P_dmax
=
(N°
channels)
·
----------^V----^c---^c--²-----------
2Π² ⋅ R_load
+
I_q
⋅
V_cc
P_dmax = 2 · ( 3.0 ) + 0.5 = 6.5 W
(Heat Sinker)
R_{Th c-a}
=
1_----5_---0_{-----–-----}T_{---a---m-----b----m----a---x-}
P_{d max}
–
R_Th
j-c
=
-¹---⁵---⁰-----–----⁵----⁰-- – 5.0
6.5
=
10°C /W
In figure 21 is shown the Power derating curve for the device.
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