Here the 35W power audio amplifier circuit based on LM391. Inductor L1 is constituted by 20 coils of wire, with thickness 0.9mm, round resistor R16. The transistors Q3-4 are the final amplification section, it should be placed on heatsink. If are used the Q3-4 in packing TIPxxxx they can be placed straight above in PCB.… Read More »
25W Hi-Fi Audio Amplifier based LM1875 – Circuit Manual
The manual circuit for 1W Stereo Audio Amplifier using LM386N
Parts List: R1-2-4-5=270Ω R3 = 2.7Ω VR1 = 10KΩ Log. Pot. TR1 = 470KΩ Trimmer IC1-2 = LM388 C1 = 100uF/25V C2 = 100nF C3 = 10uF/25V C4-5 = 22uF/25V C6 = 47nF
This is the stereo headphone amplifier circuit diagram, built based LM4809. This circuit can be used for stereo headphone amplifier circuit for home audio system, microphone preamplifier, personal computers and PDA headphone amplifier and more. The LM4809 is known as a stereo audio power amplifier capable of delivering 105mW per channel of continuous average power… Read More »
This is a logarithmic amplifier circuit based on National operational amplifier LM11C. Unusual frequency compensation provides this logarithmic converter a 100 us time continual from 1 mA down to 100 uA, escalating from 200 us to 200 ms from 10 nA to 10 pA. Optional bias electric current compensation can give 10 pA resolution from… Read More »
This is the diagram of 4W stereo power amplifier built based stereo power IC LM2877 with a few of external components. The circuit required single power supply with voltage range of 6VDC – 24VDC. Heatsink is a must to prevent over heating on the IC.
The following diagram is 16W audio amplifier circuit. The circuit built based 2 pieces of power IC LM383 in bridge connection, so this amplifier is an bridge amplifier. This is an old amplifier, LM383 is discontinued, so this LM383 might be difficult to find. You can use ECG1232, TDA2002 or TDA2003 as the replace for… Read More »
The following diagram is the circuit diagram of telephone amplifier, build based small amplifier IC LM386. This is a easy build telephone amplifier There is no extra electrical power supply required to power up the telephone amplifier circuit, as it draws power from the telephone line itself. The amplifier will supply fairly very good volume… Read More »