Monday, December 12, 2011

400 and 600 WATT AMPLIFIER WITH IRFP460 MOSFET CIRCUITS

Actrk 400/600 Watt
Two versions of a robust module capable of delivering high powwer for extended periods.  The Actrk400 uses 6 n-channel Mosfets in the output stage to deliver around 400 watts into 4 ohms while the Actrk600 uses 12 n-channel Mosfets in the output stage to deliver power in excess of 600 watts into 4 ohms.  One constructor has achieved almost 900 watts with the Actrk600 layout using 12 IRFP460 Mosfets.
Actrk 600W schematic

[read here...]

Saturday, December 3, 2011

BA5406 Stereo Amplifier Circuit

BA5406 Stereo Amplifier Circuit
In the circuit diagram shown, BA5406 is configures to deliver 5×2 watts into 4 ohm loudspeakers at a supply offer voltage of 9 volts. Capacitor C3 is a power supply filter capacitor. C11 and C12 are input DC decoupling capacitors for the left and right channels. C3 and R2 forms a Zobel network for the left output whereas C6 & R3 forms identical for the correct channel.

Purpose of the Zobel network is to cut back oscillations and improve high frequency stability of the amplifier. Potentiometers R5 and R6 serves as the quantity control for the left and right channels. CapacitorsC4 and C8 couple the outputs of the amplifier to the speakers. C9 and C10 are noise filtering capacitors. C1 and C5 are bootstrap capacitors for the left and right channels.
[read here...]

Wednesday, November 30, 2011

uA 741-Square Wave Generator

uA 741-Square Wave Generator
A square wave generator with IC UA741 range shown here.The circuit uses positive feedback to the Schmitt trigger action and negative feedback to measure the time of the waveform.

Let us assume that the output is high and the capacitor C1 is fully discharged.C1 now begins to charge through R2 and C1 R1.When tension rises above the junction of R3 and R4, the output changes rapidly totally negative voltage.C1 Now begins the unloading and reloading in the direction.Again contrast, when the negative voltage across C1 falls below that at pin 3, the circuit is returned quickly to totally positive repetitions value.The output endless cycle.

The square wave frequency can be varied by varying POT R1.The frequency range of the circuit depends on the value of R3, R4 and C1.
[read here...]

Monday, November 28, 2011

9V Portable Headphone Amplifier

9V Portable Headphone Amplifier

After several requests of the correspondents, the decision to design a headphone amplifier 9V power was finally taken. The main requirement was to feed the circuit by a common, PP3 (transistor radio) alkaline batteries. Therefore, the circuit implementation of a low current draw was absolutely necessary, while retaining high quality.

The emergence of low-noise 5534 operational amplifier at a reasonable price was much appreciated by audio designers. Now it is difficult or impossible to design a specific phase that has the performance of 5534, without the complexity unacceptable. 5534 operational amplifiers are available from various sources, in a conventional 8-pin dil format. This version is internally compensated for gains of three or more, but requires a small external capacitor (5-15pF) for unity gain stability. The 5532 is a convenient pack of two 5534s in an 8-pin device with internal unity gain compensation, since there are no spare pins.

The 5534 / 2 is a low distortion and low noise device also has the ability of low-impedance load to full voltage swing, while maintaining low distortion. It is fully output short-circuit. Therefore, this circuit is carried out with a single 5532 chip forming a pair of stereo amplifiers, invest, have a current gain of about 3.5 alternating and capable of delivering up to 3.6 V peak to peak 32 Ohm load (corresponding to 50mW RMS) less than 0.025% total harmonic distortion (1 kHz and 10 kHz).

Considering that the average current drawing a power of 15 mW per channel is about 12-13mA (both channels driven), this headphone amplifier will become a "must" for many DIY enthusiasts who need a device High quality, high performance laptop.
[read here...]

Sunday, November 27, 2011

Preamplifier Bass and Treble Controls

Preamplifier Bass and Treble Controls

Need a tone control, this module can be inserted into the chain between the Control Center and power amplifier. The circuit is based on an original design by Reg Williamson, published in Electronics World + Wireless World, circuit ideas, January 1991.

The tone control circuit will take the form of any of the traditional low treble adjustment, or the type of shelves, which is similar to a "tilt" control, but with separate bass and treble. Asymptotic slopes for both are about 4dB/octave, but begin to level off at 100 Hz and 10 kHz, with a maximum of ± 15 dB at the ends of the audio band.

Component values ​​in parentheses are the shelving of control. In this case, the platform starts around 250 Hz and 4 kHz, flatten to a maximum of ± 6dB an octave above or below the central point is 1 kHz. Reactive elements for low-end includes a generalized impedance converter, which simulates an inductor in series with a resistor (spinner).

When set to the centers of their respective electrical controls, equalizers reactive elements are almost out of circuit. With these settings, the circuit behaves as a unity gain amplifier with 100% negative votes. Still, the reactive elements can be changed completely with a DPST on / off.

As with the other modules in this series, each electronic card can be fitted in a standard: Hammond extruded aluminum cases are well suited to accommodate the tables in this preamp. In particular, instances of size 16 x 10.3 x 5.3 cm or 22 x 10.3 x 5.3 cm look very good when stacked. See below an example of the possible arrangement of the front and back of this module.
[read here...]

Saturday, November 26, 2011

150W LM12 Audio Amplifier

150W LM12 Audio Amplifier
LM12 operational amplifier can output currents up to 10A. The LM12 in encapsulated in TO-3 with 4 pins, can support up to 800W and has enough internal protections to prevent slacks from over-currents or over-heating.

You can use LM12CL with 30 V maximum voltage or LM12C with 40V maximum. The L1 coil has 40 turns 1mm copper, coiled over R4. If you use LM12CL it is recomended to have toroidal transformer 2 x 22V. The output must be between 7 and 12A. Filtering capacitors must have at least 20.000 uF. LM12 must be mounted with screws on a big heatsink (=< 1.50 C/W) and electric isolated form the heatsink.

via: electroschematics.com
[read here...]

Friday, November 25, 2011

200M FM Transmitter Simple Circuit

200M FM Transmitter Simple Circuit
FM transmitter circuit very stable and simple given here. With an adaptive antenna, the transmitter can reach a range of about 200 meters. Transmitter met this year and got a few good results. Let's see how the circuit.

A condenser microphone (K1) is used to collect the sound transmitted. The capacitor C1 is a DC decoupler and the audio signal is coupled to the base of Q1 which connects a preamplifier.R2 and R3 are the resistances of polarization of Q1. Amplified sound signal will be available at the collector of Q1 and, together with the emitter of transistor Q2 through capacitor C4 and inductor L1 1mH.

C4 capacitor decouples the DC component of the preamplifier output. Q2 does the work of the oscillator and modulator. Inductor L2 and capacitor C5 variable tank circuit is necessary to create oscillations. Capacitor C6 is the feedback capacitor. The FM modulated wave will be available at the collector of Q1 and is transmitted through the antenna A1.
[read here...]

Wednesday, November 16, 2011

170W Audio Power Amplifier With LM4651&LM4652

170W Audio Power Amplifier  With LM4651&LM4652
The combination of controller IC LM4651 and LM4652 Class D MOSFET power amplifier IC power amplifier solution provides a high efficiency, suitable for powered speakers, subwoofers and amplifiers car quality.

The LM 4651 is a fully integrated conventional pulse width modulator (PWM) driver, which contain low-voltage circuit, short, overshoot, and thermal shutdown circuit protection. The IC has a standby function which shuts the pulse width modulation, minimizing the current bid.

The LM 4652 is a fully integrated H-bridge power MOSFET IC in a TO220 power pack. The IC has a temperature sensor to alert the LM4651 when the die temperature exceeds the threshold limit.

Used together, LM4651 and LM4652 as a simple, compact, efficient, high quality audio power amplifier complete solution for protection, usually seen only in class AB amplifiers.

The maximum efficiency of this circuit is 85% to 125 W with an expected attenuation of greater than 100 dB. The THD at 10W, 4 ohm, 10 - 500 Hz max. 0.3%. The supply voltage can not exceed ± 22V.
[read here...]

Wednesday, November 9, 2011

LM358N - DEW Sensor

The following schematic shows a simple DEW sensor circuit diagram using LM258N IC. As the humidity around the circuit goes up, the resistance in the DEW sensor increases. When the resistance reaches a pre-specified level, the circuitry displays a warning message, and shuts down the external device

LM358N - DEW Sensor


Under normal conditions, resistance of the dew sensor is low (1 kilo-ohm or so) and thus the voltage at its non-inverting terminal (pin 3) is low compared to that at its inverting input (pin 2) terminal. The corresponding output of the comparator (at pin 1) is accordingly low and thus nothing happens in the circuit.

When humidity exceeds 80 per cent, the sensor resistance increases rapidly. As a result, the non-inverting pin becomes more positive than the inverting pin. This pushes up the output of IC1 to a high level. As a consequence, the LED inside the opto-coupler is energised.

At the same time LED1 provides a visual indication. The opto-coupler can be suitably interfaced to any electronic device for switching purpose. Circuit comprising diode D2, resistors R5 and R6 and capacitor C1 forms a low-voltage, low-current power supply unit. This simple arrangement obviates the requirement for a bulky and expensive step-down transformer.
[read here...]

TGS813 Gas Alarm

This toxic gas alarm circuit is sensitive to less than 100 ppm of carbon monoxide. This alarm is useful for simple gas boats, sheds and cabins. You could save a life. Some of the companies listed in the Appendix to offer plans and kits for various toxic gas sensors.

Alarm of toxic gases it utilizes a tin-oxide-semiconductor. A coil of thin wire heated by a battery 12 V via IC1 and IC2, the which pulses the voltage to the coil of the sensor, saving a significant amount of energy. Zener diode Dl provides a constant voltage to the filament coil sensors. resistance of the sensor reduces the sensor is exposed to toxic gases Such as hydrogen, carbon monoxide and propane. Reduced to the resistance of the sensor, the SCR gate voltage increases. When the gate threshold voltage is reached, the SCR fires and a buzzer alarm is activated. Once activated, the bell and the switches S1 Should Be used to reset the alarm. Since the sensor has a good deal of thermal inertia, S1 must be off or open for about three or four minutes after the initial activation, allowing the sensor to stabilize, thus avoiding false alarms. Sensitivity control R7 set to the Desired value, before the activation of the SCR.

for more details about TGS813  Gas  Alarm  Circuit please visit http://www.free-circuit.com/toxic-gas-detector-and-alarm-circuit-with-tgs813/
[read here...]

Friday, November 4, 2011

Stereo Amplifier Circuit with BA5406

Stereo Amplifier Circuit with BA5406Stereo Amplifier Circuit with BA5406

In the this circuit diagram, BA5406 is configured to deliver 5 x 2 watts at 4 ohm speakers to a supply voltage of 9 volts. The capacitor C3 is a power supply filter capacitor. C11 and C12 are decoupling capacitors DC input for the left and right. C3 and R2 form a Zobel network to output the left, while C6 and R3 is the same for the right channel.

Zobel network purpose is to reduce vibrations and improve the high frequency stability of the amplifier. Potentiometers R5 and R6 serves as a volume control for left and right channels. C8 pair CapacitorsC4 and the amplifier outputs to the speakers. C9 and C10 are the noise filtering capacitors. C1 and C5 are starting capacitors for left and right channels.

Notes.
  • BA5406 requires a proper heat sink.
  • Supply voltage range is 5 to 15V DC.
  • I used 9V DC for powering the amplifier.
  • The power supply must be well regulated and filtered
[read here...]

Sunday, October 30, 2011

Siren Generator Circuit Using UM3561 IC

UM 3561 is a low cost siren generator designed for use in toy applications. The UM 3561 IC can generate Multi siren tones simulating Police siren, Ambulance siren, Fire brigade siren and Machine gun sound. The IC has an inbuilt oscillator and tone selection pins. It is easy to make a siren generator with only a few external components. Only one external resistor and a speaker driver transistor are sufficient to make a simple siren generator.
Siren Generator Circuit Using UM3561 IC
Note:
By changing the pin connections of Sel.1 (Pin6) and Sel. 2(Pin 1) it is easy to change the siren tones.
Sel 1Sel 2Tone
Pin 6 Pin 1
NC NC Police siren
+3V NC Fire Engine sound
Gnd NC Ambulance Siren
NC +3V Machine Gun sound

Supply voltage Min. 2.4VTyp 3V Max 3.5V
Operating current Min - -180 uA

for more details about UM3561 Siren Generator Circuit please visit http://electroschematics.com/4820/um3561-siren-generator-design-2/
[read here...]

Water Switch Sensor Using S201S02 IC

The following circuit shows about Water Switch Sensor circuit based on the S201S02 IC. Features: two closely spaced metal rings are used as the water sensor mechanism.

water circuit switch sensor can be used as applications for: rain alarm, watertap leak detectors, water level sensors for bathroom water heaters, wetness checker for flower pots and more.
Water Switch Sensor Using S201S02 IC
Water Switch Sensor Using S201S02 IC
Working principle of this circuit is very simple. When the sensor rings are bridged by water, an isolated electric switch turns on to activate the load (an alarm, for instance) connected through its switching contacts. Here, the renowned S201S02 solid-state relay (IC1) is wired as the electronic switch.

for more details about water switch sensor circuit  please visit http://electroschematics.com/6259/water-switch-sensor-circuit/
[read here...]

1 Hz Pulse Frequency Generator using IC 555

This is a 1Hz pulse frequency generator circuit using timer IC 555 which is wired as an Astable Multivibrator. The output pulses can be indicated visually by the LED. An Astable Multivibrator, often called a free-running Multivibrator, is a rectangular-wave generating circuit. This circuit can be used in applications that require clock pulses

We can set the 555 to work at the desired frequency by selecting the right combination of resistances & capacitance.

Frequency = 1.44 / {(R1 + 2R2) * C1}

Also, 555 can produce waves with duty cycle else than the 50 % cycle.

Duty Cycle = (R1 + R2) * 100/ (R1 + 2R2)
where duty cycle= Ratio of time period when the output is 1
[read here...]

Wednesday, October 26, 2011

Infrared transmitters using LM3909

Infrared transmitters using LM3909
This is an infrared transmitter circuit of the signal is small and using a power supply of 1.5 V only. by the main electronics are the two LM3909 (oscillator IC LED Flasher) Normally, we tend to put it to work as a simple flashing light circuit. Use a source of low-power 1.5 V, which is working now easier to use transistors. The high frequency is very simple, just change the high frequency device only. C1 and R1 is less than the highest frequency.
[read here...]

Sunday, October 23, 2011

LM3900 Audio Mixer Circuit

 LM3900 Audio Mixer Circuit LM3900 Audio Mixer Circuit

Audio mixer circuit consists of 4 four-channel amplifier (LM3900) two microphone inputs and two audio inputs are available directly online at this circuit. By adding the parallel with this circuit, you can increase the number of entries according to applications. Each input is connected to the inverting terminal of the LM3900.

The amplifier built in each section amplifies each audio input separately and fed to the output terminals. The output terminal of each channel is connected to a single output line with a resistance no greater than 680 and produces a mixture of audio output with low noise. This audio mixer circuit does not use a low impedance input sources to the mix of ideals. Capacitors C1 to C4 are decoupling capacitors corresponding channels. C5 is the decoupling capacitor production.
[read here...]

Monday, October 10, 2011

TV Remote Jammer Using 555 IC

TV Remote Jammer Using 555 ICTV Remote Jammer Using 555 IC

The TV remote control transmits television signals as pulses of frequency around 37.5kHz. Each button on the remote control is pressed or equivalent has a pulse signal codes. This remote transmits pulses of the circuit block of the same frequency as the remote to your TV confuse decoding the transmitted signal.

The heart of the circuit is the 555 timer IC in astable circuit works mode.The output series of pulses at a frequency of 18 kHz to 48 kHz by simply adjusting the 5K potentiometer. What you do is adjust the potentiometer until frequeny jives to its distance from the TV or until the signal is ignored by television.
[read here...]

Tuesday, September 20, 2011

Fm Wireless Microphone Circuit

Easy FM wireless microphone

This FM wireless microphone is easy to build and has a large benefit of transmission (about 300 meters, while outdoor). Regardless of its small component count and 3V operating voltage that will easily penetrate the excess of some floors of an apartment development. It can be adjusted everywhere, while in the FM band (87-108MHz) and its transmissions can be picked up at any ordinary FM receiver. The coil (L1) should be about 3 mm in diameter, with five rounds of 0.61 mm copper wire. You are able Tx frequency range by simply adjusting the distance between the coils. The antenna should be half or quarter of an extended wave (100 MHz 150 cm or seventy-five centimeters).

FM wireless microphone circuit description: The audio amplifier stage (T1) is a conventional common emitter amplifier. The 47nF capacitor isolates the microphone from the base voltage to the transistor and only allows AC signals to pass. The LC tank circuit T2 occurs, the feedback capacitor C5 and the parallel LC circuit L1, C4. The coupling capacitor (C6) directs the signal to your amplifier RF (T3).

FM Wireless Microphone calibration circuit: Location of the transmitter 10 feet of a FM radio. Place the radio in a 89 to 90 MHz Spread the coil in the coil L1 frequency tuning also sought.
[read here...]

Thursday, September 15, 2011

30W VHF FM Broadcast Amplifier

The 30 watt amplifier circuit shown below provides an appropriate power boost with an input of 4 watt up to 6 watts. The circuit is designed to cover 88-108MHz FM Broadcast Band. However, the circuit is very stable at my place and provides a clean-output through seven (7) element Butter-worth low-pass filter.
30W VHF FM Broadcast Amplifier
The heart of the circuit is 2SC1946A VHF RF power transistor. The transistor is specifically designed to operate at frequencies up to 175 MHz, with very good results.

The feedline is decoupled. The current amplifier can be more than 5 amps. All coils are made of 16gauge wire rod (copper or silver wire can do better) and HF RFC may be central torus (as shown in the image) or 6-hole ferrite R1 bead.C3 and snubber circuit forms, while R2 and C6 prevent the amplifier self-oscillation in VHF, it is sometimes necessary to add 180 ohms in parallel with the amplifier will L7.That to dispel UNDESIRABLE VHF thereby reduce the spurious level.

The 60Watts VHF power amplifier using the above circuit. 2SC1946A Two transistors are arranged at 90 degrees to each other and their results were combined using "Network Power Combiner". It is very difficult to combine skills in the VHF and UHF

[read here...]

Monday, September 12, 2011

Remote Control Circuit using NE555 & LM567

Remote control circuit consists of two parts, one is the transmitter and the other is the receiver. A simple schematic diagram of the remote control. IC transmitter transmitter circuit is controlled by NE555. Receiver circuit works by the frequency of the signal, which is emitted by the transmitter circuit. Transmission frequency of the signal must be equal to the decoder frequency receiver circuit. The frequency generated NE 555 is the same as the receive frequency of the IC LM 567.


Resistor R1 is a variable receiver to facilitate the adjustment process. The system works well when the circuit is ready. The first step is the optimization through the transmitter is turned on continuously, while the receiver R1 to set the value of being able to detect the signal from the transmitter. The second part is the receiver is controlled by LM 567. The following is a schematic drawing receptor.


In the image at the top of each channel is designed with a different frequency. Given the bandwidth of the frequency detection signal LM 567, between the frequencies on which they owe a big enough difference, let's try with a difference of 5 KHz.
[read here...]

Thursday, September 8, 2011

Metal Detector using CS209A

Metal Detector using CS209AThis metal detector using CS209A made by Cherry Semiconductor. The CS209A is a bipolar monolithic integrated circuit for use in metal detection / proximity sensing applications.The CS209A metal detector IC has two on-chip regulators current, the oscillator and low-level feedback circuits, peak detection / demodulation circuit, a comparator and two complementary stages.The oscillator output, along with an external LC network provides controlled oscillations, where the amplitude is highly dependent the Q of the LC tank. The demodulator senses the negative peak of the oscillator wrap and provides a demodulated waveform as input to the comparator. The comparator sets the state of the complementary outputs by comparing the input of the demodulator to an internal reference.

The detector is a single coil 100uH. The IC has an oscillator integral part of the strangulation of an external LC circuit is the inductance that is changed by the proximity of metal objects. Is the change in the oscillation that is amplified and demodulated. LED 1 will light and the buzzer will sound when the inductance has changed. Installation is easy: R5 is adjusted with the LC away from any source of metal for the LED lights and buzzer. The control is reversed so that the LED turns off and stops ringing. When the shock comes in contact with a metal object that alters its inductance, LED and buzzer are activated.
[read here...]

Thursday, September 1, 2011

DC Power Delay based on SCR

DC Power Delay based on SCR

The circuit diagram shown here is a simple circuit DC power delay, which is based on an SCR (Silicon-Controlled Rectifier). This circuit is very useful and can be used in many applications. The operation of this circuit is very simple. When input power is applied to the capacitor C2 charges through resistor R2 when the voltage on the capacitor just above the voltage of the Zener diodes D3 breaks, breaks and H1 SCR is triggered and the power delay will be available in late OUT.



Notes.
  • The circuit must be assembled on a good quality PCB.
  • The Zener diode must be rated half the input supply voltage.
  • The current capacity of the circuit depends on the SCR and here it is 4A.
[read here...]

Saturday, August 27, 2011

50 Watts Mosfet Audio Amplifier

50 Watts Mosfet Audio Amplifier50 Watts Mosfet Audio Amplifier



The first stage of the amplifier is a differential amplifier based on transistors Q1 and Q2. Capacitor C8 is the dc input coupler, C1 R1 limits the input current and capacitor passes high frequency signals. The second stage is the stage driver consisting of transistors Q3 and Q4. Output stage is a complementary push-pull stage based MOSFETs IRF530 and IRF9530.Output attaches the loudspeaker with the inductor L1. Network consisting of R15 and C5 is designed to reduce noise. Capacitors C6 and C7 are the filters of the power supply. R6 is preset to adjust the quiescent current.
[read here...]

10 Watts Mosfet Audio Amplifier

10 Watts Mosfet Audio Amplifier

The diagram shown here is a MOSFET amplifier circuit 10W of sound that only requires a single source. Single railway material rarely used in power amplifiers class-B. However, for low power applications like this is very thin. Actually I have this circuit a old cassette player is still working and republish as it is. The BD512 and BD522 power MOSFETs is obsolete now and you can use any other power MOSFET game instead of them.



Transistors Q1 and Q2 are connected as a Darlington pair works as a preamp. R3 preset controls the quiescent current, while R2 provides. Output is coupled to the speakers through capacitor C4. Capacitor C5 is the power supply filter and C2 is the input DC decoupling capacitor.



Notes.

  • The circuit can be assembled on a vero board.
  • Use 30V DC for powering the circuit.
  • Do not expect much performance from this amplifier.
  • Capacitors C3, C4, C5 must be rated 50V and C2 can be 10V.
  • Use a 8 ohm 15W speaker as load.
[read here...]

18 Watts Mosfet Audio Amplifier

18 Watts Mosfet Audio Amplifier18 Watts Mosfet Audio Amplifier



This circuit is an audio amplifier capable of delivering a decent output power with a minimum no: of the parties, with remarkable sound quality. The amplifier uses a single transistor and two MOSFETs and resistors and capacitors some feedback loop in a small scheme.This can bypass may offer a huge 18Watts into 8 ohm speaker or a speaker 30 W at 4 ohms.



For best performance and stability of some components, high-quality well-regulated DC power supply is needed. This is very essential to reduce noise and achieve a constant output power at different loads. A good voltage regulator capable of delivering CC over 2 Amps @ 40V can be used.You can expect a power supply design very soon here in the food section.

[read here...]

Thursday, August 25, 2011

30 watt Audio Amplifier using TDA 2040

30 watt Audio Amplifier using TDA 2040An 30 Watt audio amplifier circuit with TDA2040 shown here. TDA2040 is class AB amplifier monolithic integrated audio Pentawatt available in the package. The IC has a low harmonic distortion, cross low over the distortion and has a built in short circuit protection circuit.



In the circuit of two TDA2040 ICs are connected in BTL (bridge tied load) configuration to provide an output of 30W into a 8 ohm speaker to + /-16V DC. Capacitor C1 is a decoupling capacitor DC input. Network consisting of components R2, C4, R3 provides information to IC1 as R7, C6, R8 network provides information of IC2. Red C5, C9 and R5, R9 provides high frequency stability. Capacitors C2, C3 filters positive power rail while the capacitors C7, C8 filters negative power rail.

[read here...]

Tuesday, August 23, 2011

Stereo Audio Amplifier using TDA 2822

TDA2822 is a monolithic integrated audio amplifier can be configured in stereo mode or bridge (BTL). The IC has low crossover distortion, low quiescent current and is available in 16 pin DIP package power. The TDA2822 may be operated from a supply voltage range of 3V to 15V. The main applications are headphone amplifier TDA2822, portable audio, radio, mini headphones, preamp etc. The IC can deliver an output power of 0.65W per channel into a 4 ohm speaker 6V @ HV mode 1.35 W stereo and a speaker 4 ohm high voltage supply 6V @ bridge mode.


Stereo Audio Amplifier using TDA 2822

IC TDA2822 stereo set shown in Figure 1. The left channel input is applied to the noninverting input (pin 1) of the first built in the amplifier stage and the right channel input is applied to the noninverting input (pin 16) of the second amplifier. The inverting input of these built in amplifiers are grounded separately using 1000uF capacitors (C5 and C6). The amplified outputs (left and right) are available at pins 6 and 11 of the IC. The outputs are attached to the respective speakers, using capacitors C1 and C2 respectively. The branch capacitor resistance (ohms 0.1uF and 4.7) connected via the speakers are designed to improve stability and avoid high frequency oscillations. C7 is the power supply filter capacitor.



The output of the amplifier TDA2822 can be increased by use in mono using the bridge configuration shown in Figure 2. The audio input is applied to the noninverting input of amplifier built for the first time. The non-inverting input of the second built-in amplifier to ground. The inverting input of these amplifiers are based with the C9, C11 capacitor branch. Branches R5, R6 C8 and C10, are to improve stability and avoid high frequency oscillations. Capacitor C12 is used for filtering the power supply



Notes.



The circuit can be assembled on a Vero board.

The power supply can be anything between 3 to 15V DC.

The power supply used for this circuit must be well regulated and free from any sort of noise.

Optional 10K potentiometers can be added at the input lines for controlling the volume.

It is better to mount the TDA2822 on an IC base.
[read here...]

Sunday, August 21, 2011

FM Receiver based on CXA1019

FM Receiver based on CXA1019Its a high quality FM receiver circuit based on IC CXA1019 . CXA1019 is a monolithic silicon bipolar radio FM / AM receiver IC for Sony. Built in circuitry within the CXA1019 includes RF amplifier, mixer, oscillator, amplifier, quadrature detection circuit, tuning LED driver control electronic volume, FM detector, etc. HF section is only used in this circuit. The IC can be powered by a figure between 3 to 7 V DC and can lead to an 8 ohm speaker

[read here...]

Monday, August 15, 2011

Simple Fire Alarm Circuit based on LDR

Simple Fire Alarm Circuit based on LDR

Here is a simple fire alarm circuit simple based on LDR and a pair of lamps for the detection of fire.The alarm works by detecting the smoke produced during fire.The circuit produces an audible alarm when the fire with smoke



When there is smoke in the light bulb will directly fall LDR.The LDR resistance will be low and therefore the voltage across it (below 0.6 V). The transistor is off and there is enough smoke happens.When to mask the light of the fall of LDR, LDR resistance increases and so do the voltage across the transistor will it.Now empowers ON.This IC1 and the power outputs 5V.This tone generator IC UM66 (IC2) to play music will be amplified by IC3 music.This (TDA 2002) to boost speaker.Resistor R6 is to protect the transistor when it becomes R4 towards the resistance values ​​down. Resistance R2 and R1 form a feedback network for the TDA2002 and C1 couples the feedback signal from the union of R1 and R2 to the inverting input of the same IC.



The diode D1 and D2 in combination falls 1.4 V to give the rated voltage (3.5 V) at UM66. UM 66 can not support more than 4V.

[read here...]

Thursday, August 11, 2011

Car Subwoofer filter using OP Amp IC TL072

Car Subwoofer filter using OP Amp IC TL072

Here is the circuit diagram of simple and easy subwoofer filter which will be operated from a 12V DC supply. Such a circuit is incredibly helpful in Car subwoofer applications. The circuit is nothing however a low pass filter whose pass frequency will be adjusted between 60 to 160 Hz.



The circuit is intended round the TL072 twin BIFET opamp IC. Out of the 2 opamps within the chip, IC1A is wired as a buffer. The left and right audio inputs when mixing is fed to the input of the IC1A using the DPDT switch S1. Switch S1 is that the section control switch which might be used to create the subwoofer in section with different speakers.



When S1 is in position {2, 180 degree phase shift are induced.POT R7 will be used for controlling the level. IC1B forms the low pass filter whose pass frequency will be controlled by adjusting the twin gang POT R13.

[read here...]

Tuesday, August 9, 2011

Subwoofer Low Pass Filter using TL062

Subwoofer Low Pass Filter using TL062

Many low pass filter circuits for subwoofer are given here and this can be simply another one. The circuit given here using the opamp TL062 from ST Micro electronics. TL062 is twin high input impedance J-FET opamp that has very low power consumption and high slew rate. The opamp has wonderful audio characteristics and is extremely appropriate for this circuit.



Out of the 2 opamps within TLC062, 1st one is wired because the mixer cum pre amplifier stage. The left and right channel are connected to the inverting input of IC1a for mixing. The gain of 1st stage will be adjusted using POT R3.The output of the first stage is connected to the input of second stage through the filter network comprising of parts R5,R6,R7,R8,C4 and C5. The second opamp (IC1b) is a buffer and also the filtered output is offered at the pin 7 of the TLC062.

[read here...]

Sunday, August 7, 2011

1 Watt Portable FM Transmitter

1 Watt Portable FM TransmitterThis Simple Portable FM transmitter includes a limiter, a microphone amplifier and a PLL digital tuning. All the components are placed on one circuit board. The RF power is switchable between 1 W (HI) and 0,2 W (LO).

The schematic diagram is split into 3 parts: RF part (numbered from 1), PLL (numbered from 30) and audio part (numbered from 50). Connect a 6 V / 0,1 A bulb to the output and set the correct frequency on PLL. Set the RF power to HI. currently activate the transmitter. you must tune it on a receiver. perhaps you may stretch coils of the L1. Fix the L1 in position when the tuning voltage (on Q3) is in range 4-9 V. Then use C15, C16 and C17 to regulate the best power (the highest light of the bulb). Then you'll be able to connect antenna and audio signal. change R1 till the audio sounds as loud because the alternative stations.

Technical specifications 1 Watt Portable FM Transmitter

Supply voltage: 12 V from accumulator or regulated power supply
Supply current (HI/LO): 270/170 mA
RF power HI: 1 W
RF power LO: 0,2 W
Impedance: 50-75 ohm
Frequency range: 87,5-108 MHz
Modulation type: wide-band FM
Modulation inputs: line, mic, RDS/MPX
PCB dimensions: 11,3 x 8,8 cm

[read here...]

Friday, August 5, 2011

Integrated Transmit IC for Dual-Band Cellular Phones

Integrated Transmit IC Dual-Band Phones
The MAX2369 may be a dual-band, triple-mode complete transmitter for cellular phones. The device takes a differential I/Q baseband input and mixes it up to IF through a quadrature modulator and IF variable-gain amplifier (VGA). The signal is then routed to an external bandpass filter and upconverted to RF through an SSB mixer and RF VGA. The signal is additional amplified with an on-board PA driver.

The MAX2369 is meant for dual-band operation and supports TDMA for the PCS band additionally as TDMA and AMPS for the cellular band. the required mode of operation is chosen by loading knowledge on the SPI™/MICROWIRE™-compatible 3-wire serial bus. The MAX2369 then routes the signals to the acceptable ports looking on that band is chosen. The MAX2369 includes 2 RF LO input ports and 2 PA driver ports, eliminating the necessity for external switching circuitry.

The MAX2369 takes advantage of the serial bus to line modes like charge-pump current, high or low sideband injection, and IF/RF gain balancing. it's packaged in an exceedingly tiny (7mm x 7mm) 48-pin QFN package with exposed paddle.
[read here...]

Wednesday, August 3, 2011

Portable Mixer Block Diagram

The image below shows a Block diagram of the entire mixer that includes four Input Amplifier Modules followed by four in-out switchable Tone management Modules, one stereo Line input, four mono Main Faders, one stereo dual-ganged Main Fader, four Pan-Pots, a stereo Main Mixer Amplifier Module and two additional Tone management Modules switchable in and out for every channel, inserted before the main Left and Right outputs.

Obviously this layout is rearranged at everyone want. An astonishing feature of this design lies within the fact that a whole stereo mixer as shown below within the Block diagram attracts but 6mA current!


Portable Mixer Block Diagram
The basic arrangement of this circuit comes from the recent Quad magnetic pick-up cartridge module. The circuit was rearranged to address microphone input and a single-rail low voltage provide.

This low-noise, absolutely symmetrical, two-transistor head amplifier layout, allows the utilization of a traditional FET input Op-Amp as the second gain stage, even for terribly sensitive microphone inputs.

The voltage-gain of this amplifier is varied by suggests that of R9 from 10 to one hundred, i.e. 20 to 40dB.
[read here...]

Monday, August 1, 2011

LM 390 based on 2-Way Intercom

LM 390 based on 2-Way Intercom
This is a really easy 2-way intercom circuit primarily based on a LM390 audio amplifier circuit . the intercom circuit is a stand-alone electronic communications system intended for limited or private dialogue. For this circuit you'll use a 8 ohms speaker, one for each station and require a vi volts dc power offer. Gain management will be done by capacitively coupling a resistor (or FET) from pin vi to ground.

The LM390 Power Audio Amplifier is optimized for 6V, 7.5V, 9V operation into low impedance loads. The gain is internally set at twenty to stay the external part count low, however the addition of an external resistor and capacitor between pins 2 and vi wil increase the gain to any value up to 200. The inputs are ground referenced while the output is automatically biased to at least one 0.5 the provision voltage.
[read here...]

Thursday, July 28, 2011

IRF44 Mosfet based on 100 Watt Inverter Circuit

IRF44 Mosfet based on 100 Watt Inverter CircuitIRF44 Mosfet based on 100 Watt Inverter Circuit

This inverter circuit can offer a really stable 230V Output Voltage. Frequency of operation is decided by a VR1 and is generally set to 60 Hz. varied “off the shelf” transformers can be used. Or Custom wind your own for best results. additional MosFets can be paralleled for higher power. it's recommended to own a “Fuse” within the Power Line and to perpetually have a “Load connected”, while power is being applied. The Fuse ought to be10 Amps per one hundred watts of output. the ability leads must be serious enough wire to handle this High Current Draw.

IRF44 Mosfet
Absolute Maximum Ratings of IRF44 Mosfet
  • Continuous Drain Current (25°C, 10V) = 49 A
  • Continuous Drain Current ( 100°C, 10V) = 35 A
  • Pulsed Drain Current = 160 A
  • Power Dissipation = 94 W
  • Gate-to-Source Voltage = ± 20 V
  • Avalanche Current = 25 A
  • Operating Junction = -55 to + 175
[read here...]

Monday, July 25, 2011

LM3875-High Audio Amplifier 56W

LM3875-High Audio Amplifier 56W
The LM3875 is an audio amplifier for high power output capable of delivering 56W of continuous average power to a load 8. The performance of the LM3875, utilizing its maximum instantaneous auto temperature (° Ke) (Spike ™) protection circuitry, places it in a class above discrete and hybrid amplifiers by providing a yes, dynamically protected area of safe operation (SOA). SPIKE protection means that these parts are fully protected against output overvoltage, voltage surges caused by shorts to the supplies, the peak temperature thermal runaway, and instantaneous.

This amplifier circuit is based on the non-inverted GainClone standard configuration. I did some calucaltions the feedback resistor and other components in order to check the gain, etc. For more background on the calculations relevant to GainClones in the background section.

LM3875-High Audio Amplifier 56WParameters IC LM3875

Output Current 6000 mA.
Offset Voltage max, 25C 10 mV.
Gain Bandwidth 8 MHz.
Supply Min 20 Volt.
Supply Max 84 Volt.
Supply Current Per Channel 30 mA.
PowerWise Rating 2 3750 uA/MHz.
Slew Rate 11 Volts/usec.
Input OutputType Not Rail to Rail.
Max Input Bias Current 1000 nA.
Special Features AvCl>10.
Function Op Amp.
Channels 1 Channels.
Temperature Min 0 deg C.
Temperature Max 70 deg C.
[read here...]

Friday, July 22, 2011

12 watt FM Transmitter circuit

12 watt FM Transmitter circuit12 watt FM Transmitter circuit

The advantages of FM modulation is free from the influence of the disturbance of air, bandwidth (broadband) is larger, and the high fidelitas. Compared to the AM system.

FM transmitter is a modification of the FM transmitter on the market (s Saturn type 038). several series of modifications and additions can produce energy Boster number to about 12 watts.

of the series after this work is quite good, the signal generated is stable and strong enough
time in no hurry to do it directly, but usually do each part in sequence so that the error may be earlier

the first part of the work is in the oscillator, after the raft can try to turn radio waves in free mode and set the radio volume so clearly audible hiss. turn the core Koker whistle on the radio is, if you get a signal in a robust and stable set of oscillator has been working with both.

the next section can start at the raft, after the end of the second set trimer (C8 and C11) in the buffer, in turn can feed even the largest steel cables and the older children. If the series works well, there are approximately 0.25 watts

for more resources that can be added over the wider range Boster 12 watts, so the distance will be increased to up to seven times.
[read here...]

Wednesday, July 20, 2011

Audio Amplifier Using IC LM4780

Audio Amplifier Using IC LM4780Audio Amplifier Using IC LM4780

Explore power amplifier integrated circuit from National Semiconductor LM4780. What's so special? Well, first of all - a very low harmonic distortion. In general, manufacturers indicate the maximum power of his ingenious craft regularly with the harmonic content of 10%. At the same chip, CT in the specified maximum power is only 0.5%! Therefore, it is the most honest of all mikruha've found.

The chip implements two identical amplifier channels and features are given for the stereo amplifier. Circuit can also operate in mono - the inclusion of the bridge. In this case, the power output at CT = 0.5% of 120 watts. Other features remain virtually unchanged.

LM4780 IC Fiture
  • Features SPiKe Protection
  • Low external component count
  • Quiet fade-in/out mute mode
  • Wide supply range: 20V - 84V
  • Signal-to-Noise Ratio ≥ 97dB (ref. to PO = 1W)

Audio Amplifier Using IC LM4780Audio Amplifier Using IC LM4780
[read here...]

Sunday, July 17, 2011

LM2678-5.0 on 5Volt Switching Regulator

LM2678-5.0 on 5Volt Switching RegulatorLM2678-5.0 on 5Volt Switching Regulator
This is the circuit diagram of a 5V power regulator based on LM2678 IC. The LM2678 series of regulators are monolithic integrated circuits that provide all the necessary functions required for a switching regulator money and can handle loads up to 5A. The IC has more than 90% efficiency and has to load and line regulation. The LM2678 is available in three fixed output voltages (3.3 V, 5V, 12V) and an adjustable output version. The IC is also filled with a bunch of l features such as thermal shutdown, current limiting and power on / off.

Note:
  • The circuit given here is based on the version LM2678-5.0 which gives an output of 5V.
  • The power supply for the circuit can be anything between 8 to 40V DC.
  • The feedback wiring must be placed as away as possible from the inductor L1.
  • Do not use loads that consume more than 5A.
  • A heat sink is seriously recommended for the IC.
[read here...]

Friday, July 15, 2011

Audio Surround Decoder circuit diagram

Audio Surround Decoder circuit diagram
This circuit has been created to design a decoder circuit that will function in a module that produces surround sound audio.

The operation of the circuit starts up and transport the stereo surround sound signal quality information on the master volume circuit. This will drive the left channel connected to LCH Model TL072 IC1A IC1B and attached to the right channel Rch. The outputs of these operational amplifiers serve as the input buffer for the next stages of the circuit. IC2C is responsible for the sum of the signals from left and right to power the center speaker output, while IC2D is responsible for increasing the phase difference between left and right, which is encoded in the two channels and be fed to the rear speakers. It is necessary to ensure that the negative terminals from the rear speakers is not grounded, since it will only work in parallel with the main speakers.



The output of the power unit regulated IC2D takes audio to rear speakers. This would lead to the creation of sense of separation, according to the size of the room. This will incorporate signal amplifier IC5 MN3004 sound delay that has 512 steps. From IC4 MN3101 is a timing signal, which provides synchronization of IC5 as it functions as an oscillator in the circuit. C17 variable capacitor regulates the delay in the circuit. The presence of filters in the circuit is in order to avoid the noise that occurs during the process.

These filters can be adjusted to cut the frequencies above 8 kHz and below 100 Hz, to be able to drive the rear speaker. The rear speaker is small and that their entry is encoded with a bandwidth of 100 Hz to 8 KHz. The filters are built around the IC6A / B is also an output buffer. A potentiometer is placed on each output to aid in the adjustment and regulation of speakers and amplifiers. The energy supplied in the circuit is 15 V and each output can drive a single power amplifier.

List Compoment
R1-2-7-8-12-13-18-19-20 : 47Kohm
R3-4-5-6-21-22-34-35 : 10Kohm
R9-10-11-14-15-16-17 : 15Kohm
R23-24-25-33-36 : 100ohm
R26-27-28-31-32 : 100Kohm
R29-30 : 5.6Kohm
C1-8 : 47uF/25V
C2-7-9-14-23 : 47nF
C3-6 : 1uF/100V
C4-5-10 : 33pF
C11-12-15 : 10uF/25V
C13 : 82nF
C16 : 18pF
C17 : 100pF mini adjustable capacitor
C18 : 2.2nF
C19 : 4.7uF/25V
C20 : 100nF
C21 : 10nF
C22 : 180pF
C24 : 150nF
RV1-RV2 : 2 X 10Kohm Log. pot.
RV3-4 : 10K Log pot.
D1 : 1N4148
IC1-6 : TL072
IC2-3 : TL074
IC4 : MN3101
IC5 : MN3004

[read here...]

Wednesday, July 13, 2011

12 Volt car Battery Monitor Circuit

12 Volt car Battery Monitor Circuit12 Volt car Battery Monitor Circuit

This circuit can be used to monitor the voltage level of a car battery. When the battery voltage is 11.5V or less the transistor Q1 is on and D1 glowing.When LED battery voltage is between 11.5 to 13.5 V, the transistor Q2 is on and the glowing LED D2 .

When the battery voltage is above 13.5 V, the transistor Q3 is on and the LED D3 will be bright. The 12 volt control can be connected between terminals A and B and for the convenience of using LEDs of different colors.

List component of Monitor status battery 12 volt
-R1,R3,R6: 1k 1/4W Resistance
-R2: 100K 1/4W Resistance
-R4,R5,R7,R8: 3.3K 1/4W Resistance
-D1: LED red color
-D2: LED yellow color
-d7: LED green COLOR
-D2,D4,D5,D8,D9: 1N4148 diode 1 ampere
-D6: BZX79C10 diode Zener 10 volt
-D10: BZX79C12 diode Zener 12 volt
-Q1,Q2: BC547 NPN transistor
-Q3: BC557 PNP transistor
[read here...]