TDA7266D
d Dissipating Copper Area:
Dissipated Power:
The max dissipated power happens for a THD near 1% and is given by the formula:
2
VCC
Pdmax(W) = 2 ------------- + I q V CC
2-R----l
π
2
This gives for: Vcc = 9.5V, Rl = 8Ω ,Iq = 50mA a dissipated power of Pd = 5W.
Thermal Protection:
The thermal protection threshold is placed at a junction temperature of 150°C.
Package Thermal Characteristics:
The thermal resistance Junction to Ambient obtainable with a GND copper Area of 3x3 cm and with 16 via
holes (see picture) is about 15°C/W. This means that with the above mentioned max dissipated Power (Pd=5W)
we can expect a 75°C, this gives a safety margin before the thermal protection intervention in the consumer
environments where a 50°C ambient is specified as maximum
The Thermal constraints determine the max supply voltage that can be used for the different Load Impedances,
this in order to avoid the thermal Protection Intervention.
The max. dissipated power must be not in excess of 5W , this at turns gives the following operating supply volt-
ages:
Load (Ohm)
Supply Voltage (V)
4
6.5
8.5
9.5
14
6
8
16
e Filter Capacitors Positioning:
The two Ceramic capacitors C2/C7 (100nF) must be placed as close as possible
respectively to the two Vcc pins ( 6 - 15) in order to avoid the possibiltiy of oscillations arising on the
output Audio signals.
Package Informations:
You can find a complete description for the PowerSO package into the APPLICATION NOTE AN668 available
on web.
Here we want to focalize the attention only on the the Dissipating elements and ground layer.
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STMICROELECTRONICS [ ST ]
