This audio amplifier designed uses two LM3886 per channel, in parallel circuit, based on the PA100 parallel amplifier detailed in National Semiconductor's application note - AN1192. This amplifier can deliver about 50W into a 8-ohm speaker and 100W into a 4-ohm speaker. This is a stereo amplifier and therefore 4 LM3886s are used.

The LM3886 circuit is in a non-inverted configuration, so the input impedance is determined by the input resistor R1, i.e. 47k. The 680 ohm and 470pF resistor capacitor filter network is used to filter out the high frequency noise at the RCA input. The 220pF C4 and C8 capacitors are used to shot out the high frequency noise at the LM3886 input pins.
I used high quality audio grade capacitors at several locations: 1uF Auricap at the input for DC blocking, 100uF Blackgate for C2 and C6, and 1000uF Blackgate at the supply filter.
 |
LM3886 Power Amplifier Schematics |
The PCB is designed in a way that the power ground is separated from the signal ground, as you can see from the below layout. The signal ground is located in the middle and surrounded by the power ground. There is a thin trace near C5 connecting them. The PCB layout is done by using PADS PowerPCB 5.0. I think it is a powerful layout software.
Amplifier Printed Circuit Board (PCB) |
Amplifier Printed Circuit Board Bottom |
 |
Amplifier Printed Circuit Board Top |
 |
Amplifier Printed Circuit Board |
Amplifier Power SupplyThe power supply used is a regulated power supply. I used 10000uF per rail before the LT1083 regulator. After the regulator, I have 100uF on the regulator board. The advantage of using regulator is that the power supply ripple voltage is removed. If power regulation is not used, I can hear very little 50/100Hz hum from the speaker.
The high current MUR860 diode is used to ensure high current flow. The voltage regulator used is LT1083, it can provide about 8A of current. Transformer used here is a 500VA 2x 25V. The power supply is then regulated by 2 LT1083, after the regulation, the voltage is 30V.
 |
Power Supply Recomended |
I did some DC measurement and the result is quite good, I got 7 mV of DC offset at the speaker terminal. The voltage difference between the output of the 2 chips is less then 1 mV.
The sound of this amplifier is similar to my LM3875 amplifier, which is very clean and detail. It has no hum, no hiss and no noise. Compared to the LM3875 Gainclone, this amp can deliver twice the power to my 4-ohm speaker, and it improves the dynamics and bass punch a lot.
Source :
http://www.shine7.com/audio/pa100.htm
Related Posts :
1 W mini audio amplifier circuitIn this circuit requires only three components , namely IC TDA7052 , and 2 capacitor electrolyte. Ac… Read More...
Low Voltage Amplifier Circuit with IC BA518This Circuit use IC BA518 or you can use the IC BA547 , this is low mono power amplifier. Maximum po… Read More...
120 Watt power amplifier with IC TDA2025Minimum voltage require 12 Volts and maximum voltage require 40 Volts DC . This circuit is very simp… Read More...
30 Watt subwoofer amplifier circuitThis circuit use IC TDA1004A to main operation .IC is very nice and durable if used properly and cor… Read More...
Small Power Amplifier with IC TDA1908Schematic circuit power amplifier TDA1908 , or you can use IC TDA1908A . The circuit simple and easy… Read More...
18 W stereo amplifier circuitTDA1009 circuit amplifier , this circuit is stereo amplifier and simple schematic .Minimum voltage r… Read More...
TDA2610 power amplifier circuitOn this schematic need ,Power Supply with voltage : 15 -35 V, if voltage is under 15 volt so the so… Read More...
HiFi Amplifier circuit schematicThis is HiFi amplifier use the IC TDA1111 . The circuit is quite easy to use, but the constraints on… Read More...
Amplifier Circuit with IC AN7143On this Integrated circuit power amplifier use IC AN7143 but you can use this following IC : … Read More...
5W power amplifier with IC TDA1016This circuit use IC TDA1016 , minimum require voltage for this circuit 3 volt and maximum require vo… Read More...
Very simple stereo amplifier circuit , with only need 4 componentsThis is very very simple circuit audio amplifier based on IC7057T , you just use 3 compo… Read More...
20 Watt Schematics power amplifierThis circuit is mono amplifier use IC TDA1010A .Minimum voltage require 4V and maximum voltage 24V. … Read More...
Schematic Audio Amplifier with IC AN5265Schematic Description :This Circuit Require voltage 12 -26 Volt. Good Voltage use is 16 Volt , Becau… Read More...
Schematic Audio Power Amplifier with IC AN7105This Schematic Circuit Audio Amplifier use IC AN7105 , minimum voltage 1,5 volt and maximum voltage … Read More...
2 X 20 W car amplifier circuit with TDA2009Minimum Voltage required for this circuit 8 volt and maximum voltage 28 volt . Its can use to… Read More...
Simple Amplifier SchematicThis Circuit Use a IC BA515 for operation it. This is very simple Amplifier schematic , with only ad… Read More...
Low voltage audio amplifier circuit from 0,9 voltsHere i share power amplifier based on IC TDA7236 . This amplifier require minimum voltage 0,9 volt a… Read More...
Schematic Audio Amplifier with IC AN214See this circuit below :Datasheet IC AN214Vcc … Read More...
Schematic Audio Power Amplifier with IC AN7106KThis Schematic must use the IC AN7106 because its'nt similarity, and some components. Minimum voltag… Read More...
Car Amplifier with IC LA4445This circuit using IC LA4445 , this is stereo amplifier with power output 2 X 18 Watt, with this cir… Read More...
0 Response to "200W Stereo High Power Amplifier LM3886"
Post a Comment