Vacuum Tubes Valves
Musical & effects
Yagi Uda Antennas
Metal Detector Circuits
Liquid Sensing Circuits
Light Sensing Circuits
Voltage Detector Circuits
Air-Gas Detection Circuits
Human Sensing Circuits
RF & Radiation
Optical Sensing Circuits
Free Energy Circuits
AC to DC & DC to DC
Solar Cell Circuits
Micro Power Circuits
Switching Power Supplies
Light Laser LED
Digital to Analog
Analog to Digital
Data Bus Circuits
Voltage to Pulse
Current to Voltage
Frequency to Voltage
RF Converter Circuits
Sine to Square Wave
Voltage to Current
voltage to frequency
Period to Voltage
Video Wall circuits
TV Video Circuits
Motor Control Circuits
8051 / 8052
PCB CAD Software
Car bike Circuits
555 Timer Circuits
Remote Control Toy
H Bridge Circuit
DIY HV Variable Cap
DIY PMA alternator
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
Switch control circuit diagram mcu
As shown in FIG TOPSwitch FZ chip switching power supply circuit diagram is controlled by the MCUs. The microcontroller can use inkjet printers, laser printers and other comput
Optionally extended charging pulse count switch circuit diagram
As shown, the count switching circuit comprises an electronic switch and a pulse delay circuit control.
Automatic cycle switch circuit 2
Automatic cycle switch circuit 2 It uses 555 IC as the control element} A capacitive step-down circuit; bidirectional thyristor V control relays or loads on and off time. RPi a
BT9404 type excitation switch control circuit
BT9404 de-excitation type switch by the CJ4-S contactors and JT3-21/3-type electromagnetic relays. Its control circuit is shown in Figure 7-55. Figure, KM contactors CJ4-S; KT
Precision polarity switching circuit by conventional elements
Because the loop gain of the amplifier OP depends mainly on the dry input resistor and feedback resistor ratio, so the resistance error, an error occurs opening will be a corre
Toggle Switch with relay
Pushing the button once will energize the relay. Pushing the same button a second time will de-energize the relay. Any simple momentary action push-to-make switch will do.
AC triggered switch
An AC triggered switch for low frequency signals. This is a basic ac voltage operated switch made from discrete components. Both Q1 and Q2 work as common emitter amplifiers, but the biasing of Q1 is arranged by R3 and R4 so that about 0.5V is applied to its base; so with no input signal both transistors and the load is off.
Toggle Switch with 4013
This simple circuit will energize and de-energize a relay at the push of a button. Any type of momentary action push-to-make switch can be used. Pushing the button once - will energize the relay. And pushing it a second time - will de-energize the relay
A Thermostat With Adjustable Hysteresis
A thermostat doesn't try to maintain a constant temperature. In order to do so - it would have to keep switching on and off every few seconds. Instead - it keeps the temperature within a specific range. When the preset temperature has been reached - it switches off. And it only switches on again - when there has been a significant change in...
In this circuit a non-locking push switch is used to activate a load. The load remains switched on until power is removed from the circuit. The load is represented by R5 and D1, but could be a lamp, a relay or another circuit. S2 breaks power to the circuit but could be omitted altogether. If S2 is left out, then reset would be by disconnecting...
Voltage Comparator Switch
This circuit will provide an indication whenever the input voltage differs from two defined limits, V1 and V2. The supply voltage, Vcc must be higher than the highest input voltage by at least 2 volts. One application here is to monitor a 12V car battery. V1 could be set to 14V and V2 to 11V thus giving an indication of over charge or a weak...
Thermal switches provide circuit disconnect
A microcontroller implements the proper protective action when one of the temperature monitors detects an overtemperature condition. It is sometimes easier and more cost-effective to simply disconnect the offending circuit from the power supply without involving a microcontroller. A simple thermal-protection circuit (Figure 1) includes two...
Touch Switch circuit
A touch switch is a switch that is turned on and off by touching a wire contact, instead of flicking a lever like a regular switch. Touch switches have no mechanical parts to wear out, so they last a lot longer than regular switches. Touch switches can be used in places where regular switches would not last, such as wet or very dusty areas.
The whistle switch allows you to turn on, or off, an appliance by whistling at it. I originally built the whistle switch in 1974. Do not attempt to duplicate it from the schematic below, but instead, understand the functions and duplicate these functions with more modern components.
Voltage Controlled Switch with 555
The old and omnipresent NE555 can be very good at something it was not meant for: driving relays or other loads up to 200 mA. The picture shows an example circuit: if the input level rises over 2/3 of the supply voltage - it will turn on the relay, and the relay will stay on until the level at the input drops below one third of the supply voltage.
Two buttons provide safe start
The circuit in Figure 1 provides a safety interlock that checks the actuation of two pushbuttons before enabling a relay. When you push both buttons, the circuit actuates the relay. At that point, you can release one of the switches without the relay`s switching off. The circuit was intended to lock out the engine of an underwater propulsion...
Sound Triggered Flash Schematic
No Description available.
The circuit in Figure 1 produces a single debounced pulse each time you press S1. Moreover, the circuit uses only logic power from the remote pull-up resistor, R2. You can use the circuit to detect when a key is pressed in a nonenergized device, such as a device in a system that`s just coming up from standby.
Single switch digital potentiometer
The control of electronic potentiometers in most today`s applications comes from controller-generated signals. However, a significant number of applications exist that require adjustments using manual, front-panel controls. The circuit in Figure 1 uses one IC, one switch, and 10 discrete components. It implements the interface of a single DPDT,...
microprocessor-based dual duty switch
Traditional control-system designs use separate switches to control power and various system functions, but adding a few components to a small, microprocessor-based system can combine a control function with the system`s on/off switch. For example, you can design a system to display relative humidity and temperature (Reference 1).
Printer port activates CMOS switches
The cost-effective design in Figure 1 provides control for CMOS switches without the need for an external power supply. Analog switches such as those in the MAX4663 are ideal for use in low-distortion applications. They are preferable to electromechanical relays in automatic test equipment or other applications in which you need current...
Switch intelligently controls current
The circuit in Figure 1 can intelligently control ac or dc current when connected in series with a load. The circuit "steals" its power by turning off the load at a low duty cycle. The switch uses the MOSFETs` parasitic body diode to its advantage. While the MOSFETs are off, the body diodes, along with D1 and D2, serve as two legs of a diode...
Negative Voltage Load Swtich
The idea is simply to turn off the negative voltage load. Some examples:- - Bias votlages for LCD panels - RF Amplifiers - Audio Amplifiers The good thing about this design is that i can make use of the system i/o voltage to control the on/off and this is the whole idea. However, there are many many type of load switches that turn of...
Multiple remote points control on/off switch
Sometimes, you need to remotely turn on or off a two-state system, such as a light, from multiple points. You could connect simple pushbutton switches in parallel to a single-line bus. However, if the bus simply controls a toggle flip-flop, the system must know its current state to positively ensure the new, desired state.
The alarm will switch off when the 4 keys connected to "A,B,C,D" are pushed in the right order.The circuit works because each gate `Stands` upon its predecessor.If any key other than the correct key is pushed, then gate 1 is knocked out of the stack, and the code entry fails. Pin 1 is held high by R4.
Electronic Night Light
This circuit was submitted by Adam from Canada who is still at school. I have provided the text. The two transistors are used as a direct coupled switch, Adam used 2SC711 but any general purpose transistor will do e.g. 2N3904, BC109C.
Anticipating timer switches before the button
This Design Idea offers a solution to the challenge of turning devices on or off in the past. In Figure 1, IC2 is a 555-type timer (preferably CMOS) connected as a monostable one-shot multivibrator. The pushbutton switch, S1, triggers IC2. You can replace S1 with a transistor or an optocoupler, for example. You can connect VOUT to a relay or...
Automatic Brightness Switch
Driving the highway with your high-beam headlights can really increase your visibility, but can be a blinding hazard for other drivers. This simple circuit can be wired into your headlight switch to provide automatic switching between high and low beam headlights when there is oncoming traffic. It does this by sensing the lights of that traffic....
negative-voltage power-side switch
When you need to quickly connect a negative power supply under logic control, the negative power-side switch in Figure 1 can help. Although originally intended for driving the gates of high-current MOSFETs, the MIC4451 can assume a different role. It provides complementary, low-on-resistance MOSFET switches to connect a system power-supply rail...
Heres a clap switch free from false triggering. To turn on/off any ap pliance, you just have to clap twice. The cir-cuit changes its output state only when you clap twice within the set time period. Here, youve to clap within 3 seconds.
soft-action muting switch
The circuit in Figure 1 adds a soft muting switch with power-up/power-down muting to a line-level audio circuit. R4, C1, and JFET Q1 quietly ground a signal in 100 to 200 msec when you close S1 or release it when you open S1. Potentiometer R2, set to twice Q1`s cutoff voltage, makes the on/off transition times roughly equal. R2 and D3...
Cheap pushbutton replaces rotary switch
The problem of setting any one of four modes of a µC-operated process has a straightforward solution: Have the µC check the states of some 4 bits of a µC register or an input port and then execute one of the four predetermined subroutines according to the result. The next question is how the operator sets these 4 bits or, specifically, selects a...
555 Timer Circuits
RC Model Toy Circuits
H Bridge Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
DIY HV Variable Capacitor
DIY PMA Alternator Plans
Digital Signal Integrity