40W amplifier using TDA1514
Description.
Many electronic circuits dealing with audio amplifier circuits have been published here. This is just another one and here we use the TDA 1514 high performance hi-fi amplifier from Philips. The IC has a bunch of useful features like thermal protection, mute-standby facility, low harmonic distortion etc. The amplifier operates from a dual +25/-25 V DC power supply and can deliver 40Watts output power to an 8 ohm speaker.
The audio signal to be amplified is fed to pin 1 of the IC and the capacitor C2 acts as a DC de-coupler. The resistors R3 and R4 determine the closed loop gain and it can be varied between 20 and 64 dB. Resistor R2 and capacitor C4 forms a Zobel network which corrects the loudspeaker impedance and improves the frequency response. Resistors R7, R6 and capacitor C5 are the boot-strap elements. If boot-strapping is not needed then these components can be omitted and the pin7 can be connected to pin 6, but the output power will be reduced by some 10%. R1 is the input bias resistor and it has an effect on the input impedance.
Circuit diagram.
Notes.
- Assembling the circuit on a good quality PCB will improve the sound quality.
- Use a +25/-25V DC, 4A dual power supply for powering the circuit.
- K1 can be an 8 ohm, 50W loud speaker.
- IC1 must be fitted with a proper heat sink.
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Admin Please write to me the voltage of each capacitor unit
Hi Michael power supply filter capacitors should a minimum of 4700uF 40volts, one each for the positive and negative supply. Ensure the supply line from filter capacitor to IC board is wired with >1mm dia wire and not more than 4″ in length.Still if you have some RF interferece from any near by source include 2.2K ohms 1/4 resistance between R1 and C1 this with capacitor C1 will act as a HF filter.
TANKS FOR UR CCT. I HAVE CONSTR. THE AMPLIFER AND IT WORK BUT NOISE IS TOO MUCH. PLS CAN U SPECIFIED THE CAPACITOR TO USE IN A POWER SUPPLY
An input potentiometer for gain would be connected before C2, with the wiper going to C2. Use a 10k audio (log) taper, or if you want to use a high resistance, say 50k, change R1 to 50k and C1 to 50pF.
C3 & C5 should be 25V, C7 at least 63V.
where i connect the potentiometer
electrolytics can be rated 10 or 15V
Heatsink can be a 4x2x2 inch or higher inch Finned Al type. (there is no such thing as a heat sink that is too large)
You really need to give voltages for the electrolytics. Also, just what size is a “proper” heatsink? And the power supply of 50v total x 4A would be 200w: wouldn’t half that be plenty for a 40w output?
Thanks for this idea , Actually am searching for a circuit i can use to monitor a charging, when the device is fully charge it should cut off wth a relay inbuilt and when the voltage drops the charging should continues, just an intermediary between the main source and the ups for or inverter