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Learn the power amplifier on LM4780 IC from National Semiconductor.

What's so special? Well, first of all - this is a very low harmonic distortion. Usually, manufacturers indicate the maximum power of your next brilliant crafts at THD 10%. This same chip KG at maximum specified capacity is only 0.5%! Thus, it is the honest mikruha from all I've ever encountered.
The chip's main characteristics are the following: The voltage, V 20...84
Supply current (no signal), 110 mA
Power output(KG=0,5% Uvolt=35V), W: 60
The ratio of harmonics (pout=30W, R load=8th), %: 0,03
Signal/noise ratio (a weighted), % 114


The chip implements two identical channel gain and specifications are given for stereo operation mode of the amplifier. The chip can also operate in mono - bridge connection. In this case, the output power at KG=0.5% will be 120 Watts. The other characteristics are virtually unchanged.
Watch switching circuits.
The inclusion in dual channel mode:


The inclusion in bridged mode:


The suspension elements are not too many and they all legkoperevarimye. The chip is available in your favorite all mankind the case TO-220 and ideal for mounting on the radiator. Radiator, of course, have to use very sickly, but what to do - not class D.
The plate elements (dual circuit):

The symbol in the diagram is the Value

C1 - 15

C2 - 15

C3 1uf

C4 1uf

C5 - Thu

C6 - Thu

C7 - 0,1

C8 - Thu

C9 - 0,1

C10 - MF

C11 - Thu

C12 - MF

C13 - 0,1

C14 - 0,1

R1 - 10K

R2 - 1K

R3 - 1K

R4 - kA

R5 - 1K

R6 - am

R7 - 1K

R8 - 20K

R9 Is 2.7 Ohms

R10 Is 2.7 Ohms

R11 - 20K

DA1 - LM4780