circuit wiring

This is a one watt dwelling stereo amplifier module project the use of the KA2209 IC from Samsung, which is equal to the TDA2822. It functions from three-12V DC & will work from a battery because the dormant current drain is low. It requires no warmth sink for standard use. The enter & output are both floor referenced. Maximum output will most probably be bought with a 12V energy supply & 8 ohm speaker, on the other hand it is suitable for driving headphones from a provide as low as threeV.

The Specifications of the house stereo amplifier :

D.C. input : 3 – 12 V at 200 – 500 mA max
Idle current : approx. 10 mA
Power output : > 1 Watt max. 4-8 ohms, 12V DC
Freq. Resp. : approx. 40 Hz to 200 okayHz, 8 ohm, G=10
THD : < 1 % @ 750 mW, 4-8 ohm, 12V
Gain : approx. x10 (20 dB) OR x100 (40dB)
S/N ratio : > eighty dB, G = 20 dB
Sensitivity : < three00 mV, G = 20 dB
Input Impedance : approx. 10 ok ohm

Description 

The achieve is adjustable from ten to one hundred, i.e. twenty to 40 dB. Start with remarks resistors R1 and R3 of 1k ohm, this could give a gain of ten which should be adequate for many applications. In case you need more gain, you can eliminate resistors R1 and R3.This will provide a gain of about 100, or 40 dB.The enter attenuation can additionally be adjusted by means of the potentiometer which can be utilized as a quantity keep an eye fixed on. The IC achieve ought to be okept as low as important to perform full output, with the in put potentiometer and your sign source at maximum.

Voltage Gain = 1+ R1/R2 = 1+R3/R4, however the utmost acquire without a outdoor comments is about a hundred, or fortydB. (GdB = 20log Gv)

This will okayeep the signal to noise ratio as high as feasible. Additional acquire supplied via the amplifier will cut again the S/N ratio by using a identical quantity, since the input noise figure is continuing. Other values for R1 and R3 of between 1k and 10k ohm can be used if an intermediate acquire level is necessary.

If riding a pair of headphones, you too can want a a hundred ohm resistor in sequence with each output to lower again the output stage, relying on headphone impedance & sensitivity. Make positive you begin with the quantity proper all the way down to test. Numerous headphones is additionally pushed from the amplifier in the experience you wish, considering most headphones have as a minimum sixteen ohm impedance, or extra frequently 32 ohm.

There are only some out of doors phases, the IC comprises many of the essential circuitry. R1,R2 and R3,R4 are the feedback resistors. C1 offers power provide decoupling. C2 and C3 are the enter coupling capacitors, which block any DC that might-be existing on the enters. C4,C5 block DC within the feed again circuit from the inverting enters, and C6,C7 are the output coupling capacitors. C8, R5 and C9,R6 act as Nobel networks providing a excessive frequency load to handle stability at frequencies the place loud speaker inductive reactant may turn out to be extreme. The pot offers adjustable input degree attenuation.