4 X 15 Watt Mini Power Amplifier

A lot of electronic circuits in the domain of audio amplifiers are already been published here. This circuit is a little different because it is a four channel amplifier. Each channel of this amplifier can deliver an output of 15Watts into a 4 ohm speaker. The amplifier can be operated from a single 12V DC supply and this makes it possible to use this amplifier in car audio applications too.

4 X 15 Watt Mini Power Amplifier Circuit diagram :

The circuit is based on the 15W BTL X 2 channel audio power amplifier IC TA8215 from Toshiba. Even though chip is specifically designed for car audio applications it can be also used for home audio applications. Two TA8215 ICs are used here in order to obtain a 4 channel amplifier system. The circuit is designed almost exactly as per the application diagram in the ICs datasheet. Pins 7 and 19 are the Vcc pins of the ICs internal integrated power amplifier stages and these pins are connected to the positive supply. Pin 9 is the Vcc pin for ICs internal preamplifier and it is also connected to the positive supply. Pins 13 and 14 are the internal power amplifiers ground pins and they are tied together and connected to the ground.
The internal preamplifier’s ground pin (pin5) is connected to the common ground through a 10 Ohm resistor which makes the input ground separated from the common ground by a resistance of 10 ohms and this improves the noise rejection. The 100uF capacitor works as a power supply de-coupler. The resistor networks connected to the output lines of each amplifier improves the high frequency stability. The variable resistors (R3, R4, R12 and R13) works as the volume controller for the corresponding channels.

Notes :

• Assembling the circuit on a good quality PCB is a must for obtaining optimum sound quality.
• Use 12V DC for powering the circuit.
• The ICs must be fitted with adequately sized heat sinks.
• R3, R4, R12 and R13 serves as volume controllers.
• K1 to K4 can be 4 Ohm, 20W speakers.
• This amplifier circuit can be used in a variety of applications such as car audio systems, home theater systems, personal audio systems, public address systems etc.

Source : http://www.ecircuitslab.com/2012/08/4-x-15-watt-mini-power-amplifier.html

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Battery Replacement Power Supply

Your childs battery toy has failed and you have to fix it. Once you have managed to get it apart, the battery compartment is not likely to be connected to the works or the batteries might have gone flat anyway. The solution is this switchable supply which is designed to replace from one to six dry cells. It is not intended to replace the batteries on a permanent basis, as in most cases this is not practical. The heart of the supply is an LM317T adjustable 3-terminal regulator and six trimpots selected by switch S1b. The other pole of the switch, S1a, is used to select taps on the transformer secondary, to minimize power dissipation in the LM317T. The table shows the trimpot settings for the six voltage outputs. Diode D1 and the 10µF capacitor and the LED provide power indication. This has the advantage of constant brightness which would not be obtained if the LED was run from the unregulated switchable DC.

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Self switching Power Supply

This is so useful circuit for you all. because this circuit switches itself off when no load is connected across its output terminals so you can prevent from over lording and form lots of electrical problems.According to the out put of IC 7805 you can get the voltage that you want..Maximum voltage is 12v (250MA).

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Build 10 Watt Audio Power Amplifier Circuit

10W Audio Power Amplifier Circuit

10W PA.The 10 watts power amplifier circuit with the aid of transistor describe right here is an audio amplifier with output power of 10W.Used as a low frequency type AB Amplifier. Transistor has high output present and very low distortion.This 10W audio amplifier circuit diagram using Transistor is good for small room or car audio device.This circuit is a general-purpose 10W audio amplifier for moderate-power PA or modulator use in an AM transmitter.

With better voltages and a change in bias resistors,up to 30 W may additionally be obtained.

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60W POWER AMPLIFIER CLASS B CIRCUIT DIAGRAM

60W POWER AMPLIFIER CLASS B CIRCUIT DIAGRAM

Capacitor C1 regulates the low frequencies (bass), as the capacitance grows, the low frequencies are getting louder. Capacitor C2 regulates the higher frequencies (treble), as the capacitance grows, the higher frequencies are getting quieter.

This is a class B amplifier, this means, that a current must flow through the end transistors, even if there is no signal on the input. This current can be regulated with the 500 Ohm trimmer resistor. As this current increases, the sound of the amplifier is better, but output transistors are dispatching more heat. If the current is decreased, the transistors are dispatching less heat, but the sound quality is decreased.

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Power Flip Flop Using A Triac

Modern electronics is indispensable for every large model railroad system, and it provides a solution to almost every problem. Although ready-made products are exorbitantly expensive, clever electronics hobbyists try to use a minimum number of components to achieve optimum results together with low costs. This approach can be demonstrated using the rather unusual semiconductor power flip-flop described here. A flip-flop is a toggling circuit with two stable switching states (bistable multivibrator). It maintains its output state even in the absence of an input pulse.

Flip-flops can easily be implemented using triacs if no DC voltage is available. Triacs are also so inexpensive that they are often used by model railway builders as semiconductor power switches. The decisive advantage of triacs is that they are bi-directional, which means they can be triggered during both the positive and the negative half-cycle by applying an AC voltage to the gate electrode (G). The polarity of the trigger voltage is thus irrelevant. Triggering with a DC current is also possible. Figure 1 shows the circuit diagram of such a power flop-flop. A permanent magnet is fitted to the model train, and when it travels from left to right, the magnet switches the flip-flop on and off via reed switches S1 and S2.

Circuit diagram:

In order for this to work in both directions of travel, another pair of reed switches (S3 and S4) is connected in parallel with S1 and S2. Briefly closing S1 or S3 triggers the triac. The RC network C1/R2, which acts as a phase shifter, maintains the trigger current. The current through R2, C1 and the gate electrode (G) reaches its maximum value when the voltage across the load passes through zero. This causes the triac to be triggered anew for each half-cycle, even though no pulse is present at the gate. It remains triggered until S2 or S4 is closed, which causes it to return to the blocking state.The load can be incandescent lamps in the station area (platform lighting) or a solenoid-operated device, such as a crossing gate. The LED connected across the output (with a rectifier diode) indicates the state of the flip-flop. 

The circuit shown here is designed for use in a model railway system, but there is no reason why it could not be used for other applications. The reed switches can also be replaced by normal pushbutton switches. For the commonly used TIC206D triac, which has a maximum current rating of 4 A, no heat sink is necessary in this application unless a load current exceeding 1 A must be supplied continuously or for an extended period of time. If the switch-on or switch-off pulse proves to be inadequate, the value of electrolytic capacitor C1 must be increased slightly.

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10W audio power amplifier with bass boost

As the amplifier circuit also uses a number of frequencies to drive the loudspeaker, the bass frequencies will be reduced. Therefore need to be plugged the bass-boost control at fedback loop amplifier, this is done to overcome the decline in quality.


Graph bass can reach a maximum at +16.4 dB @ 50Hz.

This circuit can be connected directly to the CD player, tuner, and tape recorders. Q3 and Q4 must be in pairs with a heatsink.

Adjust the volume control at minimum position and R3 with a minimum value of resistance as well. try enabling circuit R3 da set up to read the flow of about 20 to 25mA. Wait for 15 minutes, connect the ground at J1, P1, C2, C4 C3dan. Connect also C9 at the output ground.

For his series of power supply you can use the following scheme that fits perfectly with this amplifier.

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Usb Power Socket Circuit Diagram

Today, almost all computers contain logic blocks for implementing a USB port. A USB port, in practice, is capable of delivering more than 100 mA of continuous current at 5V to the peripherals that are connected to the bus. So a USB port can be used, without any trouble, for powering 5V DC operated tiny electronic gadgets. Nowadays, many handheld devices (for instance, portable reading lamps) utilise this facility of the USB port to recharge their built-in battery pack with the help of an internal circuitry.Usually 5V DC, 100mA current is required to satisfy the input power demand. Fig. 1 shows the circuit of a versatile USB power socket that safely converts the 12V battery voltage into stable 5V.

Circuit diagram:

Fig. 1: Circuit of USB power socket

This circuit makes it possible to power/recharge any USB power-operated device, using in-dash board cigar lighter socket of your car. The DC supply available from the cigar lighter socket is fed to an adjustable, three-pin regulator LM317L (IC1). Capacitor C1 buffers any disorder in the input supply.Resistors R1 and R2 regulate the output of IC1 to steady 5V, which is available at the ‘A’ type female USB socket.

Red LED1 indicates the output status and zener diode ZD1 acts as a protector against high voltage. Assemble the circuit on a general-purpose PCB and enclose in a slim plastic cabinet along with the indicator and USB socket. While wiring the USB outlet, ensure correct polarity of the supply. For interconnection between the cigar plug pin and the device, use a long coil cord as shown in Fig. 2. Pin configuration of LM317L is shown in Fig. 3.

Author : T.K. Hareendran - Source : EFY Mag

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5000W High Power Audio Amplifier

The High Power Amplifier has great advantages are 5000W ultra-light, high-power audio amplifier, without switching-mode power supply. This ambit is of an 2 x 2,500W RMS Stereo amplifier, super-light and after switching-mode ability supply. The ambit aloof shows a channel, and the ability accumulation that it assists to the two channels. The audio ambit should be duplicated, but the ability accumulation assists to the two channels after problems.

Click To view larger | 5000W High Power Amplifier Audio Circuits Diagrams

A adapted affliction should be destined to the careful agent of the audio line, that should be of audio-high-quality, of the blazon acclimated in microphone pre amps ascribe line. The accomplished accumulation (2 channels) of 5,000W RMS it should not counterbalance added than 32 lbs, already central of an adapted brownish box.

WARNING:

This ambit is alone for abecedarian use. It contains not-isolated genitalia of the electric AC net and it can be actual dangerous. The access for the speakers are not abandoned of the calm AC net and it requests added care. This action seeks to acting a accepted ability accumulation with abundant weight and amount reduction, after necessarily to use a switching-mode ability supply.

This action cannot be accustomed in some countries for commercial-use. The columnist doesn’t accept any albatross for the anatomy as that ambit it will be applied.

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Troubleshooting STR IC Regulator Power Supply

A. Unable to start.

Can be caused by:

• No start-up voltage supply Vcc or a voltage less than 16V
• Electrolityc Capacitors supply voltage Vcc filter dry.

  

2. Led indicator blinking

If the supply voltage Vcc examined rocking. This is because the regulator of life and death because OVLO work., Die-protectionist regulators and auto start life over and over. If it is turned off Electrolityc Capacitors  usually still keep the rest of the cargo.

Can be caused by:

• Electrolityc Capacitors supply voltage Vcc filter on a pin-4 dry. Replace with a value equal to or slightly larger. - triger UVLO
• input filter capacitor on pin-1 feed dry behind the declining value - triger OLP
• Rectifier diode of the switching transformer is damaged (sometimes when examined with avo-meter looks like a still good)
• cause the supply voltage Vcc drops of the switching transformer (UVLO)
• Part damage or broken lines on the feedback circuit of the voltage regulator through B to photocoupler - triger OVP
• Electrolityc Capacitors dry filter voltage B - triger OVP
• One of the output voltage of the switching transformer secondaries there is a short (over load) - triger OLP
• Soft start capacitor value decreases - triger OLP

3. Noise arising (noise)

Can be caused by:

• Transformer windings slack.
• If there are ceramic capacitors - can sometimes cause interference noise due to its characteristic piezoelectrik like crystal resonator. Replace with film capacitors.

4. When the st-by normal stress. But when the power is on the regulator directly off protectionism no voltage on the secondary this part. Electrolityc Capacitors  are still storing charge.

Can be caused by:

• Sensor OVP small value resistor on pin-2 to the ground so that the value of delayed triger to OLP or OCP.
• Regulator IC is damaged

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Note: Be careful when the regulator is not working. Because of Electrolityc Capacitors  may still have a charge when turned off.

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Tube Power Amplifier 35W Push Pull

Tube Power Amplifier 35W Push Pull is made using a tube and eventually compiled configuration push-pull amplifier. Tube Power Amplifier 35W Push Pull tube til it using EL-34 as the amplifier end.

In the power amplifier that is made with a tube at a glance looks simple because the use of active components that are not complex. It should be noted that the use of tubes in Tube Power Amplifier 35W Push Pull require a high voltage supply, therefore in the process of making and finishing must be careful of high voltage and radiation. Detailed series of Tube Power Amplifier 35W Push Pull can be seen in the following figure.

Tube Power Amplifier Series 35W Push Pull

Sign Components Tube Power Amplifier 35W Push Pull
R1 = 470K 0.5 W
R2-5 = 2K2 0.5W
R3 = 150K 0.5W
R4 = 220K 0.5W
R6-10 = 56K 0.5W
R7 = 3.9K 0.5W
R8 = 220R 0.5W
R9 = 1M 0.5W
R11 = 39K 1W
R12-23 = 180K 0.5W
R13-21 = 820K 0.5W
R14-22 = 5K6 0.5W
R15-20 = 680K 0.5W
R16-19 = 100K 0.5W
R17-18 = 3K3 1W
R24 = 470R 2W
TR1-2 = 470R 1W Variable (adj. 270Ω)
C1-3-6-7 = 0.1uf 630V
C2 = 220pF 600v
C4-5 = 16uF 550V
C8-9 = 0.1uF 630V
C10-14 = 0.47uF 630V
C11-13 = 25uF 40V
V1 = E80CC
V2 = E80CC
V3-4 = EL34
Rectifier tube = Z2C
Audio Transformer for T1 = 2x EL34 Push Pull

Power amplifier with tubes often become the choice for a small slewrate so that the resulting audio quality is guaranteed. Tube Power Amplifier 35W in the circuit that is required to supply a high DC voltage is +220 VDC ddengan order to work properly.

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