Homemade microcomputer "local sound card"

We know that the signal from the microcomputer motherboard to the horn is actually a pulse-width modulated digital signal, which
is output through a 0.25W/8fl small speaker with a diameter of less than 2.5 inches. If the playback signal belongs to a type of fixed-frequency whine prompt sound, the effect
is okay. If it is a voice or music signal, the output volume will be low and the frequency response of the signal will be poor. Therefore,
the "fool-type" power amplifier integrated circuit TDA7052 with excellent frequency response performance and extremely simple assembly is selected for sound amplification in this circuit. Its main
parameters are: power supply voltage is 3~15,V, voltage gain value is 40dB; frequency response is 20Hz~20kHz, the maximum output power
can reach 1W when powered by +5v ; its harmonic distortion when outputting 0.1W is only is 0.2%. The input impedance is lOOkn. Tr)A 7 05Z has few external components, high output power , no need for heat sinks, and internal overload protection and noise suppression circuits, making it particularly suitable for this application.