TL783C based 48V PHANTOM POWER SUPPLY circuit with explanation

This is a simple 48 V regulated linear power supply design that will provide up to 60 mA of current. This circuit is based on the Texas Instruments TL783C high voltage adjustable linear regulator IC, because this device will provide short circuit protection for an input to output differential voltage of up to 125 V. AnLM317T can also be used in this circuit, but a short on the output will destroy the regulator IC. Protective diodes are included in this design to provide a discharge path around the regulator in case of an accidental reverse bias condition.

Part :
C1,C2,C3 – 220 uF 100 V
C5,C6 -10 uF 100 V
C6 -10 uF 100 VD1-D6 – 1N4002
R1 – 82 OHM 1/4 W
R2 – 1 K OHM TRIMMER
R3 – 2.7K OHM 1 W
T1 – 40 V at 0.15 A (6 VA)
U1 – TL783C

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Clap Sensitive On Off Relay Diagram Circuit

This circuit was intended to activate a relay by means of a hand clap. Further claps will turn-off the relay. An interesting and unusual feature of this project is the 3V battery operation. The circuits sensitivity was deliberately reduced, in order to avoid unpredictable operation. Therefore, a loud hand clap will be required to allow unfailing on-off switching. Q1 acts as an audio amplifier. IC1 timer, wired as a monostable, provides a clean output signal and a reasonable time delay in order to allow proper switching of the following bistable circuit. A discrete-components circuit formed by Q2, Q3 and related parts was used for this purpose, in order to drive the Relay directly and to allow 3V supply operation.

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Circuit Diagram:

Clap Sensitive on-off Relay Circuit Diagram

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Parts:

R1 = 12K
R2 = 1M
R3 = 6.8K
R4 = 220K
R5 = 2.2M
R7 = 100K
R8 = 22K
R9 = 6.8K
R10 = 100K
Q1 = BC550C
Q2 = BC328
Q3 = BC328
C1 = 220nF-63V
C2 = 22nF-63V
C3 = 220nF-63V
C4 = 22nF-63V
C5 = 22nF-63V
C6 = 47uF-25V
D1 = 1N4148
D2 = 1N4148
B1 = 3V Battery
IC1 = 7555 CMos IC
RL1 = DIL Reed-Relay SPDT
SW1 = SPST Switch
MIC1 = Electret Mic

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Notes:

A small DIL 5V reed-relay was used in spite of the 3V supply. Several devices of this type were tested and it was found that all of them were able to switch-on with a coil voltage value comprised in the 1.9 - 2.1V range. Coil resistance values varied from 140 to 250 Ohm. Stand-by current consumption of the circuit is less than 1mA. When the Relay is energized, current drain rises to about 20mA.

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On And Off Button Diagram Circuit

In this simple circuit we give the chip a little more attention than usual. It is astonishing what can be built with a 555. We are always infatuated with simple circuits using this IC, such as the one shown here. The 555 is used here so that a single push-button can operate a relay. If you press the button once, the relay is energized. When you press it again the relay turns off. In addition, it is possible to define the initial state of the relay when the power supply is switched on. The design is, as previously mentioned, very simple. Using R1 and R2, the threshold and trigger inputs are held at half the power supply voltage.

Circuit diagram:

On/Off Button Circuit Diagram

When the voltage at the threshold pin becomes greater that 2/3 of the power supply voltage, the output will go low. The output goes high when the voltage at the trigger input is less than 1/3 of the power supply voltage. Because C2, via R3, will eventually have the same level as the output, the output will toggle whenever the push-button is pressed. If, for example, the output is low, the level of the trigger input will also become low and the output will go high! C1 defines the initial state of the relay when the power is applied. If the free end of C1 is connected to Vcc, then the output is high after power up; the output is low when C1 is connected to ground.

Author: Ger Langezaal - Copyright: Elektor Electronics

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Using LV47011P car audio amplifier Diagram Circuit

Using the LV47011P audio power amplifier IC designed for 4-channel BTL power amplifier that developed for car audio system we can implement a very simple car audio amplifier electronic project that can produce an output power between 22 and 50 watts on a 4 ohms load .
This LV47011P car audio amplifier electronic project will provide a maximum 22 watts output power per channel on a 4 ohms load using a 14,4 volts DC power supply at 1% THD .
In same conditions , this car audio amplifier electronic circuit project will provide 29 watts output power at 10% THD .
This IC incorporate various functions (standby switch, muting function, and various protection circuit) necessary for car
audio system and also, it has a self-diagnosis function.
For pop noise prevention, it is recommended to use the muting function at the same time when the amplifier is turned on.
When the amplifier is turn off, turn off the power supply after turning on the muting function .
The muted state is obtained by setting pin 22 to the ground potential, enabling audio muting.
The muting function is turned on by the applied voltage of 1V or less to the resistance of pin 22. And the muting function is turn off when this pin opens.
The circuit is packaged in a Sanyo HZIP 25 package and must be heat sinked , to prevent the damage due to over heating .

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NCP2824 bassed Class D amplifier electronic project Diagram Circuit

Using the NCP2824 filterless Class D amplifier can be designed a very simple low power audio amplifier electronic project, capable of delivering up to 2.4 W to a 4 ohms load with a 5 V supply voltage.
With the same battery voltage, it can deliver 1.2 W to an 8 ohms load with less than 1% THD+N. The non−clipping function automatically adjusts the output voltage in order to control the distortion when an excessive input is applied to the amplifier.

This adjustment is done thanks to an Automatic Gain Control circuitry (AGC) built into the chip. A simple single wire interface allows to the non Clipping function to be enabled and disabled.
A programmable power limit function is also embedded in order to protect speakers from damage caused by an excessive sound level.

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TA8256BH bassed 6 watts 3 channel audio amplifier Diagram Circuit

Using the TA8256BH audio amplifier IC can be designed a very simple 3 channel audio power amplifier for audio applications that require a small power .
This IC provides an output power of 6 watts per channel (at VCC = 20 V, f = 1 kHz, THD = 10%, RL = 8 Ω).

TA8256BH audio amplifier project is suitable for power amplifier of TV and home Stereo.
Some important build in functions of these audio circuit project , based on the TA8256BH are : audio muting circuit , thermal shut down protection circuit, over voltage protection circuit .
TA8256BH power amplifier can operate over a wide range input voltage from 10 to 30 volts .

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1W BTL Audio Amplifier Diagram Circuit

The TDA8581(T) from Philips Semiconductors is a 1-watt Bridge Tied Load (BTL) audio power amplifier capable of delivering 1 watt output power into an 8-Wload at THD (total harmonic distortion) of 10% and using a 5V power supply. The schematic shown here combines the functional diagram of the TDA8551 with its typical application circuit. The gain of the amplifier can be set by the digital volume control input. At the highest volume setting, the gain is 20 dB. Using the MODE pin the device can be switched to one of three modes: standby (MODE level between Vp and Vp–0.5 V), muted (MODE level between 1 V and Vp–1.4 V) or normal (MODE level less than 0.5 V). The TDA8551 is protected by an internal thermal shutdown protection mechanism. The total voltage loss for both MOS transistors in the complementary output stage is less than 1 V.

Circuit diagram:

1 Watt BTL Audio Amplifier Circuit Diagram

Using a 5-V supply and an 8-W loudspeaker, an output power of 1 watt can be delivered. The volume control has an attenuation range of between 0 dB and 80 dB in 64 steps set by the 3-state level at the UP/DOWN pin: floating: volume remains unchanged; negative pulses: decrease volume; positive pulses: increase volume Each pulse at he Up/DOWN pin causes a change in gain of 80/64 = 1.25 dB (typical value). When the supply voltage is first connected, the attenuator is set to 40 dB (low volume), so the gain of the total amplifier is then –20 dB. Some positive pulses have to be applied to the UP/DOWN pin to achieve listening volume. The graph shows the THD as a function of output power. The maximum quiescent current consumption of the amplifier is specified at 10 mA, to which should be added the current resulting from the output offset voltage divided by the load impedance.

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Speaker to microphone converter Diagram Circuit

Description.
This circuit is a simple approach for converting a loud speaker into a microphone. When the sound waves fall on the diaphragm of a speaker, there will be fluctuations in the coil and there will be a small proportional induced voltage. Usually this induced voltage is very low in magnitude and useless. Here in the circuit the low voltage is amplified using transistors to produce a reasonable output. The transistor Q1 is wired in common base mode and produces the required voltage gain. The transistor Q2 is wired as an emitter follower to produce enough current gain. The voice quality of this circuit will not be as much as a conventional microphone but quite reasonable quality can be obtained. To set up the circuit, keep the preset R2 at around 10 Ohms and connect the battery. Now adjust R2 to obtain the optimum sound quality.

Circuit diagram with Parts list.


Notes.

• Assemble the circuit on a general purpose PCB.
• Power the circuit from a 9 V PP3 battery.
• A 3 inch speaker can be used as K1.
• All capacitors must be rated at least 15V.
• An 8 Ohm speaker or head phone can be connected at the output to hear the picked sound.
  

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Battery Saver Circuit Diagram and explanation

We presents a small electronic switch that connects a battery to the equipment for a certain amount of time when a push-button is momentarily pressed. And we have also taken the ambient light level into account; when it is dark you won’t be able to read the display so it is only logical to turn the switch off, even if the time delay hasn’t passed yet. The circuit is quite straightforward. For the actual switch we’re using a well-known MOSFET, the BS170.

A MOSFET (T2 in the circuit) used in this configuration doesn’t need a current to make it conduct (just a voltage), which makes the circuit very efficient. When the battery is connected to the battery saver circuit for the first time, capacitor C2 provides the gate of the MOSFET with a positive voltage, which causes T2 to conduct and hence connect the load (on the 9 V output) to the battery (BT1). C2 is slowly charged up via R3 (i.e. the voltage across C2 increases).

Circuit diagram:

Battery Saver Circuit Diagram

This causes the voltage at the gate to drop and eventually it becomes so low that T2 can no longer conduct, removing the supply voltage to the load. In this state the battery saver circuit draws a very small current of about 1 µA. If you now press S1, C2 will discharge and the circuit returns to its initial state, with a new turn-off delay. Resistor R5 is used to limit the discharge current through the switch to an acceptable level. You only need to hold down the switch for a few hundredths of a second to fully discharge C2.

In our prototype, connected between a 9 V battery and a load that drew about 5 mA, the output voltage started to drop after about 26 minutes. After 30 minutes the voltage had dropped to 2.4 V. You should use a good quality capacitor for C2 (one that has a very low leakage current), otherwise you could have to wait a very long time before the switch turns off! The ambient light level is detected using an LDR (R1). An LDR is a type of light sensor that reduces in resistance when the light level increases. We recommend that you use an FW150, obtainable from e.g. Conrad as part number 183547-89.

When there is too little light its resistance increases and potential divider R1/R2 causes transistor T1 to conduct. T1 then charges up C2 very quickly through R4, which limits the current to a safe level. This stops T2 from conducting and the load is turned off. The choice of value for R2 determines how dark it has to be before T1 starts to conduct. The battery saver circuit can be added to devices that use 6 or 9 volt batteries and which don’t draw more than 100 mA. The circuit can be built on a piece of experimenter’s board and should be made as compact as possible so that it can be built into the battery powered device.
Source: Elektor Electronics 12-2006

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KLX250S Kawasaki Ignition System Parts Diagram and explanation

The Kawasaki KLX250S is powered by a compact, liquid-cooled, four-stroke, single-cylinder engine displacing 249cc. A throttle position sensor (TPS) helps the 34mm semi-flat slide Keihin CVK carburetor deliver the optimum amount of fuel for all riding conditions. Here is a typical schematic of the 2007 Kawasaki KLX250S Ignition System Parts and Components Diagram.
21119 Igniter
21121 Ignition Coil
21130 Spark Plug Cap
21131 High Tension Grommet
92071 Plug Cap Grommet
92151 Bolt-Flanged-Small
92172 Screw

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