TDA7294 : 60W Power Audio Amplifier Circuit

This is the circuit diagram of 60W power audio amplifier based TDA7294. The above diagram is for single/mono amplifier only. You can build the stereo amplifier by build two similar circuit. Of course you will need to doubling the power supply too.


The TDA7294 amplifier module is a monolithic integrated circuit. It is intended for use as an audio class AB amplifier in hi-fi applications. It has a wide voltage range and output current capability, enabling it to supply the highest power into both 4 ohm and 8n ohm loads. With the addition of a handful of parts and a suitable power supply, this module will deliver 50W RMS into 8-ohm with 0.1% THD. you the user must supply a heavy duty heatsink rated at 1.4°C/W. Pin 10 is the MUTE input and pin 9 provides a STANDBY mode. Muting should always take place before standby mode is selected. Connecting these pins permanently to the supply rail (insert links) ensures that the amplifier comes on immediately on power up. Increasing the time constants R3-C6 and R4-C5 may eliminate any switch-on clicks. The IC has internal thermal protection that causes the mute to cut in at 145°C and switches the amplifier into standby at 150°C. Do not operate the module without a heatsink. The heatsink tab on the TDA7294 IC is internally connected to the negative supply rail. If the module is mounted inside an earthed metal enclosure then the IC must be insulated from the heatsink. If not, the negative supply rail will be shorted to ground.


60W Power Audio Amplifier part list:

R1=180ohm
R2-3-5=10Kohm
R4=22Kohm
R6=680ohm
C1=1.5uF 63V MKT Polyester
C2=2.7nF 63V MKT Polyester
C3-4=100nF 100V MKT Polyester
C5-6=10uF 63V Electrolytic
C7=22uF 63V Electrolyti
C8=33uF 25V Electrolytic
C9-10=1000uF 63V Electrolytic
IC1=TDA7294 on Heatsink
J1=2pin connector with 2.54mm step
J2=3pin connector
J3=2pin connector
JP1-2=2pin Jumper with 2.54mm step
All Resistors is 1/4W 1%
All Electrolytic Capacitors is Axial

Power supply circuit:

Above circuit diagram is the power supply circuit for 60W amplifier. The maximum supply voltage of the IC is +/-40V. However the maximum dissipation of the IC would be exceeded when using a 4-ohm load at that voltage. Therefore the supply voltage used should be kept down to a safe +/-30V. The mains transformer used to power the module should be rated at a minimum of 80VA. If you want to run two modules in a stereo amplifier you can use a common power supply. In this case the transformer should be rated at 150VA.

Power Supply parts list:

TR1 = 230Vac//2X22Vac --> 80VA for single Amplifier
TR1 = 230Vac//2X22Vac --> 150VA for stereo Amplifier
C1 = 22nF 630V Polyester MKT
C2....5 = 22nF 100V Polyester MKT
C6-7 = 10.000uF 63V For single Amplifier
C8-9 = 10.000uF 63V For dual Amplifier (no need if you build single amp only)
C10-11 = 1uF 63V Polyester MKT
BR1=Diode Bridge >15A
F1=Fuse 0.5A slow