Power Dissipation

Taking as reference the IC internal schematic dia-

gram we can calculate the power dissipated by the

video amplifiers.

The power dissipation of the IC is defined by a static

an a dynamic part.

The statically dissipated power is given by :







R1

+







− 3

2

− 3

input to ground resistance with a black level

The dynamic power dissipation has been calcu-

lated with a 5MHz, 80Vpp sinusoidal output signal

expression :

=







2







= 1.90W

The value is reduced by 20% (0.8 factor) because

during the flyback time there is not signal.

The total power dissipated by the IC is therefore :

One of the worst working condition of the TV set as

regards the power dissipation, is when you get

white noise on the screen, for example, when you

disconnect the TV aerial or the channels are not

properly tuned.

white noise output signal with a black level

can be measured.

With a maximum ambient temperature of 70

°Cand

a junction temperature of 150

°Ca 15°C/W heatsink

is required.

Figure 4 : Maximum Allowable Power Dissipation

versus Ambient Temperature

Figure 5 : Mounting Examples

TDA8153

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