TDA7294 problem low sound

hi
i build an amplifire with tda7294 and connect input of amp to output of y laptop and connect output of amplifire to a 4ohm/50watt speaker and put the volume of my laptop at max and the speaker sound like a 5watt speaker and after 60 second tda7294 with a huge cpu heatsink beacome very very very hot and output sound was about 5 watt
the power supply was +-33 volts and there wasnt any addotional circuit and build amplifire with datasheet circuit.input signal was at high level

so please help me where is the problem????

Did you use the recommended pcb design shown in the datasheet? If you made a different pcb design then the amplifier might be oscillating at a high frequency which will cause it to get very hot.

Hi,

Show your exact circuit. All known voltages, signals and connections.
Maybe an additional picture.

Klaus

Choice of two problems:- 1 there is a wiring fault, 2 bad layout or decoupling causing high frequency oscillations. So if you have a scope put it on the output see if you can see any wave form with no input. If its oscillating then the wave form is normally huge like+- Vcc p-p. in this case the layout and or decoupling is wrong. Often touching a sensitive part of the circuit will change the frequency or stop it, use a screwdriver. If your wiring is rubbish you might have wired it up wrong and used positive feedback instead of negative. If you have no scope build a high frequency detector, .1Mf, one end as input other side going to a diode to earth, junction of diode going of to your DVM on DCV via a 10K other side of DVM going to earth. Polarity depends on which the diodes connected. To test probe use the input signal, should get a reading.
Measure the Vcc, disconnect the amp, Vcc should not change by more then a few volts.
I am dubious about your heat sink, a big one is 250mm X 250mm X 75 mm, CPU heat sinks tend to be a lot smaller (100mm square) but fan cooled.
Frank