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
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
Motor Control Circuits
Motor Control Circuits
2Y- connection three two-speed motor contactor control circuits
Circuit shown in Figure 3-98. Motor starting and low-speed operation is controlled by a switch SA. Adjust the time relay KT, the motor can be changed from low speed to start hi
2Y- connection two-speed motor contactor control circuit of the four
Circuit shown in Figure 3-99. The low start-up circuit to the motor ( shaped connection), then automatically accelerated speed into high speed (2Y-connector) operation. Start f
PTC phase asynchronous motor circuit protection one
Circuit shown in Figure 4-2. It uses two thermal resistors, a (Rc,) is used as overload protection, another (Rt :) used as an alarm.
High-power motor control circuit summary
Circuit works (only the relevant parts of the manual draw mode): Figure a shows a circuit schematic circuit; Fig. B Typical electricity as conventional secondary circuit road;
Multi-unit slip motor speed control system synchronous operation circuit
Collaboration with the dancers balanced bridge long on the porcelain unit Sync adjustment rheostat speed control system shown in Figure 3 to 183 in FIG. Others, such as electro
Lego Double Rotation Sensor
An opto-interrupter made with Lego beams, regular parts, a 6 hole pulley wheel and an axle.
Hover Board Project
The fan, motor controller and batteries are mounted to the bottom board, so that the fan system can be wired up and tested before assembly. Once the fan system is tested the top board and bottom board can be brought together to form the hovercraft plenum chamber. The segmented skirt attaches between the top and bottom board, to channel the air...
DC Motor Reversing Circuit
A DC motor reversing circuit using non latching push button switches. Relays control forward, stop and reverse action, and the motor cannot be switched from forward to reverse unless the stop switch is pressed first.
DC Servomotor Controller
This is an experiment on the closed loop DC servomotor control system (SMC). It will able to be used for practical use with/without some modifications. The closed loop servo mechanism requires real-time servo operations, such as position control, velocity control and torque control. It will be suitable for implementation to any embedded 32 bit...
Discrete component motor direction controller
This circuit can control a small DC motor, like the one in a tape recorder. When both the points A & B are "HIGH" Q1 and Q2 are in saturation. Hence the bases of Q3 to Q6 are grounded. Hence Q3,Q5 are OFF and Q4,Q6 are ON . The voltages at both the motor terminals is the same and hence the motor is OFF. Similarly when both A and B are "LOW"...
Simple circuit controls stepper motors
Stepper motors are useful in many consumer, industrial, and military applications. Some, such as personal-transportation systems, require precise speed control. Stepper-motor controllers can be simple (Figure 1), but they require a variable-frequency square wave for the clock input. The AD9833 low-power DDS (direct-digital-synthesis) IC with an...
Circuit Generates Analog Fan-Speed Control
Fan-control circuits range from simple switches that boost the fan speed at a certain temperature, to digitally controlled fans with continuously-variable speed. High-speed/low-speed switches are inexpensive, but the sound of sudden speed changes can be annoying. Digitally controlled fans perform well, but those circuits are more costly, and the...
Circuit generates fan-speed control
Fan noise is becoming a significant issue as electronic equipment increasingly enters the office and the home. Noise is proportional to fan speed, and the airflowhence, fan speednecessary for cooling is less at low ambient temperatures. Because ambient temperature is lower than the upper design point most of the time, a fan can run slower,...
Circuit forms dc-motor switch with brake
Controlling a small dc motor without speed control sounds like a trivial task; a switch or a relay should suffice. However, several problems accompany this approach. For one, the switch, because of the inductive load and the low starting resistance of the motor, tends to wear out prematurely (with all the related sparks and EMI problems)....
Circuit protects system from overheating
The two-chip circuit in Figure 1 provides fan control and overtemperature warning and shutdown signals to protect systems from excessive heat. The circuit monitors the temperature of the pc board and the die temperature of a CPU, an FPGA, or another IC with an on-chip temperature-sensing transistor. IC1 is a temperature detector and fan driver...
bidirectional, variable-speed motor control
During the development of systems that include small motors, a simple, bidirectional motor controller with speed adjustment may be helpful. Figure 1 shows such a controller. The circuit uses everyday components whose tolerances and ratings are unimportant as long as they sustain the required voltage, current, and power. The circuit`s advantages...
Circuit provides Class D motor control
Class D audio amplifiers provide a dual benefit for battery-powered portable devices (Figure). They enhance battery life, and they produce much less power dissipation than do their linear cousins. Those features make Class D amplifiers ideal candidates for controlling speed and direction in small electric motors. The standard application circuit...
Circuit provides efficient fan-speed control
As Moore`s Law plunges us into the realm of multigigahertz processors and PCs with gigabytes of RAM, engineers face the task of removing the heat that these state-of-the-art components produce. Cooling such systems poses a dilemma. If you optimize the fan size and speed for nominal operating conditions, the system is susceptible to failure when...
Dual Channel Servo Pulse to H-Bridge Interface
The interface uses a PIC16F876 microcontroller and not much else. It performs channel mixing, current limiting, and noise rejection. Push the stick forward, both motors move forward, move the stick to the left and the robot moves left. It makes the robot very driveable. You can use a wheel transmitter meant for cars to control it, in other...
H-Bridge Motor Control Circuits
These circuits could be used as the basis for Model Railroad DCC Boosters or PWM motor controllers. The first schematic is for a basic 3 Amp - DCC Booster using the LMD 18200 CMOS, H-Bridge. Included in the design is a 5Volt regulator that supplies power to the DCC signal generation and display circuitry.
H-Bridge This circuit drives small DC motors up to about 100 watts or 5 amps or 40 volts, whichever comes first. Using bigger parts could make it more powerful. Using a real H-bridge IC makes sense for this size of motor, but hobbyists love to do it themselves, and I thought it was about time to show a tested H-bridge motor driver that didn`t...
ramp generator for stepper motors
The 555-based bistable circuit in Figure 1 can easily generate a pseudo-trapezoidal move profile. Note that the timing string of R1 and associated components does not connect to VCC, as it would in a normal circuit, but instead receives its power through a pushbutton switch.
Pulse Width Modulation DC Motor Control
Often, people attempt to control DC motors with a variable resistor or variable resistor connected to a transistor. While the latter approach works well, it generates heat and hence wastes power. This simple pulse width modulation DC motor control eliminates these problems. It controls the motor speed by driving the motor with short pulses....
Push Button Motor Control Circuits
The circuits on this page are for motor controls using Push buttons and would typically be found in commercial and industrial installations. The circuits do not show the wiring of the motors themselves as this depends on the particular motor type. The type of motor also governs the number of contacts needed for the motor side of these...
Single Phase Electronic Starter
Anovel Single-phase electronic starter circuit meant for 0.5 HP and 1 HP motors, is presented. It incorporates both over-load and short-circuit protections. A specially made current sensing device has been added in this starter to sense the current being drawn by the motor.
Small DC Motor Speed Regulator
Reverse engineered circuit diagram of a motor speed regulator out of a portable pocket tape recorder containing a single motor for all functions. This circuit works amazingly well, keeping the motor speed constant regardless of shaft load and battery voltage.
Stepper Motor Controller
I found this circuit in my files. I don`t know where it came from, but it looks like I photocopied it from somewhere years ago. I have been told that it came from "The Robot Builder`s Bonanza", by Gordan McComb. Anyway, I thought that it should be fairly useful, so I decided to post it here. The circuit is very simple and inexpensive. This is...
Stepper Motor Driver Circuit
The following diagram is for the main circuit of the motor driver. A testing version is shown near the end of this page. It is laid out differently and shows the SN7474 in logic block form and LED`s are used to indicate the motor coils being switched.
Switching regulator drives robot motor
The circuit in Figure 1 shows an example of how you can use an integrated switching regulator (ISR) to efficiently vary the speed of a permanent-magnet dc motor. In this application, the rotating head of a robot senses the presence of an oncoming object (perhaps a human). If the robot senses an object, it slows the rotation of its head to...
multiple temperature fan speed
The block diagram in Figure 1 represents a complete remote-temperature-sensing and fan-control system. The system uses an Analog Devices temperature-monitor and fan-control ASIC and a PIC16C84 µC from Microchip Technology. The ADM1022 allows you to measure the local temperature and two remote temperatures within a system. An on-chip, 8-bit DAC...
PWM fan controller
Microchip Technology (www.microchip.com) offers a family of cooling-fan speed controllers that operate in PWM mode for use with brushless dc fans (Reference 1). To control fan speed using the PWM waveform`s duty cycle, you can use either an external NTC (negative-temperature-coefficient) thermistor or one of Microchip`s PIC microcontrollers and...
Stepping Motor Driver
The circuit is not particularly susceptible to motor transients and supports FULL STEPS FORWARD, FULL STEPS REVERSE, ACTIVE HOLD, and POWER OFF aka RELEASED. If the motor does not turn then swap around the leads of ONE of the two coils. To reverse the sense of the EN signal simply rework the circuit around an XNOR gate.
Stepper Motor Circuits
Remote Control Circuits
Direction Finder Circuits
Power Control 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...
Digital Signal Integrity
Interconnection and Timing of Digital Circuits
CMOS Circuits Tutorial