TDA7294 100W Audio Amplifier
100W Audio Amplifier TDA7294.
TDA7294 is an integrated, monolithic, Class AB audio amplifier designed specifically for Hi-Fi applications. The IC has a DMOS output stage and can deliver 100W RMS into an 8Ohm speaker at +/-38V dual supply. The TDA7294 has low noise, low distortion, good ripple rejection and can be operated from a wide range of supply voltages. The IC has built in short circuit protection and thermal shutdown circuitries. The IC is available in multiwatt 15V and multiwatt 15H packages.
Description.
In the circuit TDA7294 is configured to provide 100W output power into an 8Ohm loudspeaker at +/- 38V supply. C8 is the input coupling capacitor and the input is applied to the non-inverting input (Pin3) of the IC. C3 and C9 are power supply filter capacitors while C10 and C4 are bypass capacitors. C2 is the bootstrap capacitor. RC network comprising of R1 and C1 improves the high frequency stability of the amplifier and also prevents oscillations. R2 and C6 sets the mute time constant while R3 and C5 sets the standby time constant. S1 and the mute switch and S2 are the standby switch. R5 is the input resistance and the amplifiers input impedance has a direct relationship to its value. R4 and R6 is used for setting type closed loop gain and with the used value, gain is 30dB. C2 is a feedback capacitor and it also provides DC decoupling.
Circuit Diagram.
TDA7294 100W amplifier
TDA7294 100W amplifier
Notes.
- The supply voltage range is +/- 10V to =/-40V DC.
- Heat sink is required and its thermal resistance should be around 0.038 degree Celsius/Watt.
- Use an 8 Ohm 150W speaker as the load.
- For 100W output the supply voltage must be +/-38VDC.
- The power supply must be well filtered and free of ripples.
- If ripples are present in the power supply it may cause oscillations.
- VM = 1.5V is the mute ON threshold and VM=3.5V is the mute OFF threshold.
- VSTBY = 1.5V is the standby on threshold and VSTBY = 3.5V is the standby OFF threshold.
- Typical input resistance of TDA7294 is 100KiloOhm.
- Frequency response is 20Hz to 20KHz.
- 145 degree Celsius is the threshold for thermal shutdown. Slew rate of TDA7294 is 10V/microsecond and the open loop voltage gain is 80 dB.
- Quiescent current of TDA7294 is approximately 30mA and its maximum value is 65mA.
Dear Bro. Seetharam…
thanx for the advice god bless u
Ramdas
Hi Ramdas the recommended operating point of the amplifier is with plus minus 35 volts DC the power delivered will be 70 Watts RMS into 8 Ohms load with a distortion of 0.5% for plus minus 35 volts DC you have use a transformer with a rating of 25-0-25 volts @ 3 to 4 amps per channel.
What is the actual watts of this TDA7294 amplifier
Dear Sir….
How much ampere required for driving one channel of TDA7294
Pls specify the Transformer details and Power supply details
pls reply to my mail
Hi Alex the absolute maximum voltage allowed is + & – 40volts with 30 volts transformer you will get 42 volts. The recommended voltage for 8 ohms speaker safe operation is 25 – 0 – 25volt 3 to 4 amps transformer.
can i use 30v 3 amp transformer for this circuit
Zero PCB?
can we implement this circuit on zero pcb?
Hi You can build this logic, in sequence, in discrete digital ICs and connect the output through proper interface (drivers) to the individual equipment.
Hello Sir,
How do I design a circuit that works when the main power fails On-line UPS starts, after battery gets low then the generator starts automatically untill the battery gets charged. when battery is fully charged the generator stops and power comes from the UPS till the battery goes low, when main supply comes if generator is running it should stop and UPS should charge from the main power supply. is it possible?