Reflected Infrared Light Switch

Infrared light reflected off a finger is used to activate this switch circuit.Drawing only 30uA from a 3v supply, this circuit will detect a human finger with a range of about 1 inch.  The sensor uses an inexpensive infrared LED and a matching photo diode.

3V CAPACITANCE PROXIMITY SWITCH

This circuit was designed to provide a touch activated switch function without an external power supply. It draws so little power that a single 3v battery will operate the circuit for many years.  It is discussed in more detail in the section on Capacitance Proximity Switch Technology.

3 Minute LED Closet Light

The circuit below is powered by three 1.5v alkaline AA cells.  With a finger tap to the pushbutton trigger switch, a cluster of 6 wide angle white LEDs is turned on. The lights remain on for about 3 minutes, then will turn off.  The circuit’s standby current is only a few microamps.  A set of fresh batteries should last at least 200 light applications.

The circuit uses a Schmitt trigger inverter and two transistors.  When the pushbutton switch S1 is pressed, the 10uF capacitor C1 is discharged. When the switch is released, the capacitor is charged through R1. With the capacitor C1 discharged, the Schmitt trigger output swings to 4.5v, which turns on transistor Q2. The combination of R4 and Q1 form a constant current control circuit.  The current is set about 15ma per LED.  When the capacitor charges up to about 2.3v, the Schmitt trigger changes state, turning off the LEDs.

Click on Drawing Below to view PDF version of Schematic

Noise generator 2 frequency with ic 555

This is a simple noise generator circuit. An IC Timer IC 555 is a number of major equipment. Small circuit. Suitable for various test circuits.
Operation of the circuit is when the power supply to the circuit. It will give birth to high frequency by using a circuit IC1 to a multi-state Devices Bill Brett Foster. The frequency with which R1, C1 and C2. The frequency will be out in three legs. And will be expanded with the IC2 output pin out of 5 in order to drive the speakers. The high-frequency sound. But when the switch S1, capacitor.
C1, which continue to cycle in a manner parallel to the C2 value higher density. IC1 will give birth to low-frequency out of pin 3 to IC2 then drive the speakers. This circuit can cause the audio source has two frequency.

stereo-amplifier-ic-TDA1554-22W- 22W

This circuit is a circuit-watt amplifier size at a reasonable 22W 22W. This is the mod is perfect for listening at home or in any vehicle. Is a simple circuit. Use small pieces of equipment and an IC. Is only one number TDA1554Q. And within a short-circuit protection circuit with the output.

Principle of the circuit is. Circuit to receive input on each channel C1 and C2. This will signal coupling or filter out specific signal only The left channel input signal as the right to work. So I explained just left alone. Signal to pass from C1 to the Pin 1 and pin 2 of IC1. This position will stand a horizontal leg inverter protest Amplifiers not to phase out the output pin 6. And the second leg is the leg position in a power amplifier to phase Ting. Out through the output pin 8. Which will be seen that output and second legs are legs 6 and Pin 8 are phase signals the opposite is to provide power W increases itself. Power consumption power that job. to use up about 5 A at 12V. The speaker will use a 4 ohm speakers so the sound is currently 22 watt, but if it uses any 8 ohm speaker. But Watts will be lowered again. While working in the circuit will generate heat at the IC Therefore the disc cooled.

Led light movement the audio signal with LM358- IC 4017

This is a circuit that features a running pace with a changing voice, the tiny microphone. For a frivolous fun.
Operation of the circuit when a signal is to change the MIC1 audio signal and power amplifiers to be stronger. The LM358 IC1 / 1 and IC1 / 2 classified as a circuit that changes the electrical signal of the audio signal to be square, to control the operation of pin 14 of IC2. IC2, which is connected to the circuit. The output pin voltage is out sort of leg 3, 2, 4, 7, 10, 1, 5,6, 9 and 11. On IC2 controls the signal LED lights chasing each step on the moon. The number of square wave signal to the pin 14. The R8 help restrict the current flowing through the LED accordingly.

Music box versatile using IC M3481

This is a multi-purpose integrated music box that interesting, because an IC package. Is a simple and affordable.
The main function of the circuit is the device of the circuit is IC1. This is a sound generator IC. The Christmas season. Its musical all 8 music. When the power supply LDR1 the exposure will cause voltage drop across R1 is enough to make IC1 work has output to stimulate pin 11 and pin 12 to stimulate pin B of Q1. Q2 and the current expansion drive that will be the speaker. While the circuit work if the switch S1 connected to the unique music tracks and so on, but if S1 is not connected. Circuit will play all the songs. If the switch S2 connected to the cycle When there is no light will stop play immediately. But if the switch S2 is not connected to music and no light will not stop until the song is finished playing.
Switch S3 is responsible for selecting music on, press 1 once one moves to music. The VR1 is also a tone control if VR1 is less resistance will be reduced to a lower tone. And the music will slow down play with. The R6, C3 is responsible for smooth sound more R7 forward to control the feedback stability of dc output of the circuit.