June 20, 2016

Simple Inverter Circuit from 12 V up to 120V

This is a Simple Inverter Circuit from 12 V up to 120V elevated , center - tapped (CT) control transformer and four additional components can do the operation. This circuit outputs a clean about 120 volt - 200 volt at 60 Hz and can supply up to 20 Watt. The circuit is self starting and free running. See this simple inverter circuit below :

Simple Inverter Circuit from 12 V up to 120V elevated

Transistor Q1 and Q2 use 2N5877 or similarity .If Q1 is faster and higher gain than Q2 , it will turn on first when aplly the input power and will hold Q2. Load current and the transformer magnetizing current the flows in the upper half of primary coil, and auto transformer supplies the base drive (two transistor) unti the transformer saturates.The transformator can use the 3A CT transformer an use the secondary coil for input and primary coil use to output, And input use the 12 volt secondary coil. Use 12 battery to power input , such as 12 V accu.

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12V to 220V Inverter Circuit Diagram

12V to 220V Inverter Circuit Diagrams, Even though today’s electrical appliances are increasingly often self-powered, especially the portable ones you carry around when camping or holidaying in summer, you do still sometimes need a source of 230 V AC - and while we’re about it, why not at a frequency close to that of the mains? As long as the power required from such a source remains relatively low - here we’ve chosen 30 VA - it’s very easy to build an inverter with simple, cheap components that many electronics hobbyists may even already have 12V to 220V Inverter.

12V to 220V Inverter Schematics
Though it is possible to build a more powerful circuit, the complexity caused by the very heavy currents to be handled on the low-voltage side leads to circuits that would be out of place in this summer issue. Let’s not forget, for example, that just to get a meager 1 amp at 230 VAC, the battery primary side would have to handle more than 20 ADC!. The circuit diagram of 12V to 220V Inverter Schematics our project is easy to follow. A classic 555 timer chip, identified as IC1, is configured as an astable multivibrator at a frequency close to 100 Hz, which can be adjusted accurately by means of potentiometer P1.

As the mark/space ratio (duty factor) of the 555 output is a long way from being 1:1 (50%), it is used to drive a D-type flip-flop produced using a CMOS type 4013 IC. This produces perfect complementary square-wave signals (i.e. in antiphase) on its Q and Q outputs suitable for driving the output power transistors. As the output 12V to 220V Inverter current available from the CMOS 4013 is very small, Darlington power transistors are used to arrive at the necessary output current. We have chosen MJ3001s from the now defunct Motorola (only as a semi-conductor manufacturer, of course!) which are cheap and readily available, but any equivalent power Darlington could be used.

These drive a 230 V to 2 × 9 V center-tapped transformer used ‘backwards’ to produce the 230 V output. The presence of the 230 VAC voltage is indicated by a neon light, while a VDR (voltage dependent resistor) type S10K250 or S07K250 clips off the spikes and surges that may appear at the transistor switching points. The output signal this circuit produces is approximately a square wave; only approximately, since it is somewhat distorted by passing through the transformer. Fortunately, it is suitable for the majority of electrical devices it is capable of supplying, whether they be light bulbs, small motors, or power supplies for electronic devices.

PCB layout:
PCB 12V to 220V Inverter Schematics
R1 = 18k?
R2 = 3k3
R3 = 1k
R4,R5 = 1k?5
R6 = VDR S10K250 (or S07K250)
P1 = 100 k potentiometer
C1 = 330nF
C2 = 1000 µF 25V
T1,T2 = MJ3001
IC1 = 555
IC2 = 4013
LA1 = neon light 230 V
F1 = fuse, 5A
TR1 = mains transformer, 2x9V 40VA (see text)
4 solder pins

Note that, even though the circuit is intended and designed for powering by a car battery, i.e. from 12 V, the transformer is specified with a 9 V primary. But at full power you need to allow for a voltage drop of around 3 V between the collector and emitter of the power transistors. This relatively high saturation voltage is in fact a ‘shortcoming’ common to all devices in Darlington configuration, which actually consists of two transistors in one case. We’re suggesting a PCB design to make it easy to construct this project; as the component overlay shows, the PCB only carries the low-power, low-voltage components.

The Darlington transistors should be fitted onto a finned anodized aluminum heat-sink using the standard insulating accessories of mica washers and shouldered washers, as their collectors are connected to the metal cans and would otherwise be short-circuited. An output power of 30 VA implies a current consumption of the order of 3 A from the 12 V battery at the ‘primary side’. So the wires connecting the collectors of the MJ3001s [1] T1 and T2 to the transformer primary, the emitters of T1 and T2 to the battery negative terminal, and the battery positive terminal to the transformer primary will need to have a minimum cross-sectional area of 2 mm2 so as to minimize voltage drop.

The transformer can be any 230 V to 2 × 9 V type, with an E/I iron core or toroidal, rated at around 40 VA. Properly constructed on the board shown here, the circuit should work at once, the only adjustment being to set the output to a frequency of 50 Hz with P1. You should keep in minds that the frequency stability of the 555 is fairly poor by today’s standards, so you shouldn’t rely on it to drive your radio-alarm correctly – but is such a device very useful or indeed desirable to have on holiday anyway? Watch out too for the fact that the output voltage of this inverter is just as dangerous as the mains from your domestic power sockets.

So you need to apply just the same safety rules! Also, the project should be enclosed in a sturdy ABS or diecast so no parts can be touched while in operation. The circuit should not be too difficult to adapt to other mains voltages or frequencies, for example 110 V, 115 V or 127 V, 60 Hz. The AC voltage requires a transformer with a different primary voltage (which here becomes the secondary), and the frequency, some adjusting of P1 and possibly minor changes to the values of timing components R1 and C1 on the 555.
B. Broussas
Another interesting related Circuit : DC 12V to 24V Contverter, 5000W PWM inverter, and other Inverter / Converter Circuit.
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How to mixing stereo input to mono output

Here , I will give a circuit of schemes that are used to mixing stereo input to mono output to boost  gain output . Why 2 inputs in to one because, if we need a stereo amplifier we want to become a stronger by combining the two input into one input, so that a higher power output. Actually without any circuit above we can combine stereo amplifier into mono, but the sound output less than the maximum , need for this additional combiner circuit.

How to mixing stereo input to mono output
Part List =
For balance _: R1 / R2=R3 / R4
For balance _: R1 = R3
Gain ______: R5 / R1 = R5 / R3
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June 15, 2016

Power Amplifier with digital volume control

Amplifier with digital volume control can we make predictably because the circuit is made simple with just single chip TDA8551. The circuit of Mini Amplifier With Digital Volume Control is a type BTL amplifier with 1 Watt.

Techniques for adjusting the volume in this series has been provided with a pin path control that is controlled by providing an input voltage VCC and GND. The series is also equipped with a selector mute, standby and operating.
Mini amplifier with digital volume control circuit diagram
Mini amplifier with digital volume control schematics

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High Performance Audio Power Amplifier

High Audio Power Amplifier is an important part in sound reproduction ina sound system. Audio Power Amplifier with this power IC LM 3886. Audio Power Amplifier is a highly capable and able to produce68 Watt power avg. 4Ohm load and capable of producing power 38 Watt8Ohm load.

With good sound reproduction capabilities of 20Hz-20kHz also possessed this LM3886 Audio Power Amplifier. Audio Power Amplifier LM3886 Speaker is equipped with protection that will protect the circuit output from over-voltage, under-voltage, over-loads, a short circuit power supply, thermal run-away and the temperature peak. Audio Power Amplifier LM3886 also equipped with noise reduction that can keep the audio system from noise well.

Schematic power amplifier with LM3886
Schematic power amplifier with LM3886

Feature owned LM3886 Audio Power Amplifier

  • 68W cont. avg. output power into 4Ω at VCC = ± 28V
  • 38W cont. avg. output power into 8Ω at VCC = ± 28V
  • 50W cont. avg. output power into 8Ω at VCC = ± 35V
  • 135W instantaneous peak output power capability
  • Signal-to-Noise Ratio ≥ 92dB
  • An input mute function
  • Output protection from a short to ground or to the supplies via internal current limiting circuitry
  • Output over-voltage protection against transients from inductive loads
  • Supply under-voltage protection, not allowing internal biasing to occur Pls | VEE | + | VCC | ≤ 12V, Thus eliminating turn-on and turn-off transients
  • 11-lead TO-220 package
  • Wide supply range 20V - 94V

Application of Audio Power Amplifier LM3886

  • Stereo audio system
  • Active Speaker
  • High End Audio Power TV
  • Suround Power Amplifier
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Simple 3 Transistor Amplifier

Mini 3 transistor amplifier is a simple amplifier with 50mW power drawn by 3 transitor. The series of three mini-amplifier transistors can be used for loud speaker 8 ohm load. Source voltage required to activate the mini-amplifier can be drawn from the batteries 9V. Circuit of 3 transistor amplifier is often used in simple portabe audio devices such as radios or small tape recorder. Mini-transistor amplifier circuit 3 is quite simple as shown in the figure below.

Simple 3 Transistor Amplifier

Mini-transistor amplifier circuit 3 includes type of amplifier OTL (Output Transformer Less). Mini-transistor amplifier circuit 3 is used for output coupling capacitors. Amplifier circuit is simple and suitable when used for audio amplifier experiment.
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5 Channel Equalizer LA3600

5 Channel Equalizer LA3600 [updated] ,One type of preamp tone / tone controls are the Audio Graphic Equalizer. Audio Graphic Equalizer have 2 kinds in my opinion. Namely Audio Graphic Equalizer Bar and the type of parametric type is often called parametric equalizer.

Audio Graphic Equalizer In the article this is the type of bar with 5 channels using IC LA3600. IC LA3600 is a single chip "Audio Graphic Equalizer 5 channel" that is designed specifically for the equalizer five channels. Because IC LA3600 is a special design of the equalizer circuit to make this a simple equalizer. Figure series of Audio Graphic Equalizer 5 channels with IC LA3600 as follows.

5 channel equalizer
Equalizer Schematic

Audio Graphic Equalizer circuit with IC LA3600 above can control the audio frequencies from 108 Hz to 10.8 KHz. Audio frequency which is controlled by this equalizer was 108 HZ, 343 Hz, 1.08 KHz, 3.43 KHz and 10.8 KHz. The frequency of that frequency is set based on the value of 2 pieces of capacitors in each chanelnya. So for instance want to change the center frequency of each channel value of 2 pieces of the capacitor can be changed as desired.
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