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LM12 150W high power amplifier circuit diagram

This 150W high power amplifier circuit diagram is designed using LM12 power operational amplifier made by National Semiconductor can be built audio power amplifier that can charge a maximum power of 150 watts.
Maximum allowable temperature of the output transistors is measured for power limiter control circuit which is part of the dynamic security protection. Power output stage is not connected to that pin until the voltage does not exceed 14 V (± 7 V). When the chip temperature rises above 150 ° C, output is automatically disconnected.
Circuit diagram indicates the presence of two diodes in integrated output that are designed to prevent the output voltage excursion exceed the supply voltage when the output stage is integrated inside the contretemps and override the output load is mainly inductive.
At maximum output, distortion increases to 0.05% (Ub = ± 30 V, RL = 4 ohms). Maximum current is obtained at a 2 ohm load but in this case, the distortion increases to 0.1%.
Idle current of the amplifier is between 65 and 100 mA. L1 coil has 40 turns of enamelled copper wire 1 mm in diameter, wound on the resistance R4. It mainly uses the correct operation of the amplifier with capacitive loads reaction, such as speaker separation filters.
If using a LM12CL is advisable to use a toroidal transformer which provides in secondary 2 x 22 V (in which case the power of 150 W can be obtained only on a 2 ohm load).
Integrative be screwed on to a large thermal radiator, which should be very well insulated electrically.

Circuit Diagram: 
LM12 150W high power amplifier circuit diagram

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