To drive high power subwoofer loud speaker we need power Amplifier then only we can get perfect bass sound from the input audio signal. Here IC TDA7294 Subwoofer Amplifier Circuit designed with minimum external components.
The IC TDA7294 comes in a multiwatt package hence it can be easily connected with heat sink and also the IC has thermal shutdown and short circuit protection. This IC can give upto 100 watts output power, you can use 30V dual power supply (+30V GND -30V) as power source.
IC TDA 7294
IC TDA7294- 100W DMOS Audio Amplifier with mute option from ST comes in multiwatt15V and multiwatt15H package. It is a monolithic integrated circuit, it can be used as a audio class AB amplifier in Hi-Fi field applications.
This IC has mute and stand by functions to mute the audio output the pin 10 (Vm) should be less than 1.5V and to OFF the mute pin 10 (Vm) should be greater than 3.5V. Standby ON threshold is 1.5V and standby OFF threshold is 3.5V.
Construction & Working
Use 8Ω 150W subwoofer speaker for good result, use 50V or above 30V rated capacitors in this amplifier circuit, If you don’t want to use the Vm and Vstby functions leave these pins open & make sure the presence OFF threshold voltage on these pins. Connect Audio input signal to the Non Inverting pin. If you want stand alone Volume control use 10KΩ Variable resistor at the non inverting pin followed from audio input. You can easily assemble this circuit in common prototype board, after completing the circuit construction apply dual 30V power supply.