NE555 Monostable

This is a monostable mode circuit of NE555 IC timer. Feature : timing period is 1.1msec, precision, Simple circuitry, independent output duration, 12V supply. Component : Resistor, capacitor, NE555 timer IC. [zen22142.zen.co.uk]

Basic 555 Squarewave Oscillator

The following circuit is a Basic 555 squarewave oscillator. Feature : 1 Khz tone, Simple circuitry, limit = 200 mA, inductive voltage reduced, 4.5-9 Supply voltage. Component : 555 timer IC, resistor, capacitor, Speaker, 2N3053 transistor, push button. [qsl.net]

Bicycle back Safety Light

This is a circuit of bicycle back safety light. Feature : 13 LEDs flashing, 3V supply voltage, Simple circuitry, low voltage, high efficiency, battery powered. Component : Resistor, capacitor, LED, switch, battery, 7555 timer IC. [redcircuits.com]

Four-Hour Timer

The following schematic diagram is four hour timer circuit. Feature : easy to build, 3 hours 53 minutes total time,9V supply voltage. Component : 555 timer IC, Resistor, capacitor, switch, transformer, LED, CD4040B, Relay, BC547 transistor, 1N418 diode, variable resistor. [wiredworld.tripod.com]

CPU Clock Display Circuit

This is a CPU clock display circuit. This circuit shows the CPU speed. Feature : Simple circuitry, easy to build, 5V supply, can display CPU clock. Component : 7 Segment display, Resistor, 1N4001 diode, jumper. [turbokeu.com]

Simple Temperature Regulated FAN Speed Controller Using MOSFET

The following circit is Simple temperature regulated FAN speed controller using MOSFET. Feature : + 12 V input voltage, 0-12 V output voltage, nice smooth regulation, noise removed, 47C max load, fan speed was about 3000 as usual.Component : capacitor, resistor, MOSFET P.[www.webx.dk]

Smart Battery Charger Using A Single-Transistor Circuit

The following circit is a smart battery charger using a single transistor. Featre : Simple circuitry, 13.3 VDC supply voltage, single transistor. Component : Battery, resistor, C1061 transistor, 1N4001 diode, relay, capacitor, potentiometer. [electronicdesign.com]

Single Transistor Nicad Battery Charger

This is a nicad battery charger circuit. Feature : Simple circuitry, charge nicad battery, changeable rate, single transistor, charging current 15mA or 45mA,for 1.5V and 9V battery, 12VAC supply voltage. Component : 1N4001 diode, Capacitor, 1N4148 diode, BD140 transistor, switch, resistor,transforme, Fuse.[zen22142.zen.co.uk]

Lithium Chargers

This is a lithium charger circuit. Feature : variable current 100mA-2A, simple circuitry, easy to build, inexpensive circuitry, +12V supply voltage. Component : LM741, variable resistor, resistor, zener diode, capacitor, L200. [flyelectric.ukgateway.net]

Motorcycle Battery Charger

The following schematic diagram is a motorcycle battery charger. Feature : 115 or 220V Ac supply voltage, current of 3A, full indicator, simple circuitry, 14.1 volt output. Component : LM350, Transformer, bridge rectifier, capacitor, resistor, potentiometer, 1N4148 diode, BC558 transistor, 1N4001 diode, LED, LM1458. [sentex.ca]

14 Watts Audio Amplifier

The following circuit is a Audio amplifier which can give 14 watts of power. Feature : provide 14 watts of power, a discrete power op-amp, gain of approximately 150, preamp has voltage gain of 10, has extremely low distortion, relatively insensitive to the choice of components. Component : Capacitor, Resistor, potentiometer, CA3140, LM301, 1N751 Zener diodes, Speaker, 2N3904 transistor, 2N3906 transistor, TIP2955,1N4001 diode, Inductor,TIP3055.[michaelgellis.tripod.com]

100W Guitar Amplifier Using TL072

This is a guitar amplifier using TL072. This amplifier can amplify up to 100W. Feature : 100W amplification, Simple Circutry, Elegant design, provides excellent tonal range, suit any style of playing, provide a huge amount of gain. Component : Resistor, TL072, Capacitor, Potentiometer, BC549 transistor, Switch, Diode, Zener diodes.[sound.westhost.com]

2.5 W Stereo Class D Audio Power Amplifier Using LM4663

This circuit is a 2.5 W stereo class D audio power amplifier using LM4663. Feature : Two stereo input selector, Micropower shutdown mode, Stereo headphone amplifier, no heatsink needed, “Click and pop” suppression circuitry, Delta-sigma modulator, high efficiency, single supply. Component : resistor, capacitor, LM4663, speaker, headphone.[national.com]

Balanced microphone preamp

The following circuit is a balanced microphone preamp. Feature : Simple circuitry, inexpensive, 60dB amplification, 12V supply voltage. Component : Resistor, transformer, potentiometer, ne5532, rectifier, 7812, 7912, fuse, capacitor, 7805, zener diode. [nomad.ee]

MPX4115 Barometric Pressures Circuit Diagram

Barometric Pressures Circuit Diagram

Description: The following circuit shows about MPX4115 Barometric Pressures Circuit Diagram. This circuit based on the MPX4115 IC. Features: bring the voltage down to the active range of 5 volt opamps, output is fed to the 1-Wire DS2438 A/D, available overall gain is about 12.6 (i.e. 0.68 * 2.16 * 8.58), opamp stage with a gain of U1A, capable of a gain range of 1/1 to about 8.58/1, 4.25 to 3.79 volts at sea level, 2.77 to 2.45 volts at 10,000 feet. Component: Resistor, IC, Capacitor, Variable Resistor.[davidbray.org]

1 wire Barometer Using MPX4115

This is a 1 wire barometer using MPX4115 circuit. Feature : Simple circuitry, more reliable, output voltage ranges from about 4.17 to 3.72 volts at sea level, about 3.5 to 3.04 volts at 5000 feet, gain of 4.4. Component : MPX4115, 7805 regulator, DS2438, 1N4001 diode, resistor, capacitor, 2N4403 transistor, LM358 op amp, variable resistor. [davidbray.org]

Opto isolated 1-Wire bus

The following schematic diagram is a opto isolated 1 wire bus circuit.
Feature : 1 wire in, 1 wire out, Input is fully 1-Wire compatible, slow rate limited active output, DC/DC converter.
Component : Resistor, transistor, Capacitor, Optocoupler. [home.kpn.nl]

Light Pollution Meter

This is a light pollution meter circuit. Feature : control range of about 2 to 30 microamps, Simple circuitry, easy to build, battery powered, 9V supply voltage. Component : LED, NPN transistor, Digital multimeter, Resistor, potentiometer, toggle switch, battery. [avery.home.mindspring.com]

Water-level Alert

The following circuit is a water level alert. Feature: Simple circuitry, low voltage, 1.5V supply voltage, portable unit, battery powered, low current consumption. Component : Resistor, capacitor, LED, 1N5819 diode, 7555 timer IC, piezo sounder, Battery. (redcircuits.com)

Water Level and TDS Sensor

This is a water level and TDS sensor circuit. Feature : Simple circuitry, Battery powered, 9V supply voltage, very low power consumption. Component : Resistor, capacitor, probe, battery, speaker, TLC555 timer IC, switch. [pbv.thunder-bay.on.ca]