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Motor Control Circuits
Motor Control Circuits
Speed Controller for brushed electric motors
Like most other ESCs, this one is built up using N-channel Power MOSFET`s because of their good characteristics (low DS resistance). Since this ESC has no reverse, it is not meant to be used in R/C cars or boats if reversed motor run is needed. It is more suitable for R/C airplanes. It has no BEC circuit therefore you must power the receiver and...
Stall-Motor Routing Control Circuits
This page shows some methods of track routing control for Stall-Motor type switch machines. The principle method uses a 2 Pole - Multi Position rotary switch while an alternate uses optoisolators and transistors to select the routes. The last circuits on the page are for a method of controlling the matrix electronically. This would, in theory,...
Simple PWM controller
This 555 timer based PWM controller features almost 0..100% pulse width regulation using R1, while keeping the oscillator frequency relatively stable. The frequency is dependent on values of R1 and C1, values shown will give a frequency range from about 170 to 200 Hz. Any 555 chip will do, CMOS is fine as well. Diodes are not critical, I used...
Programmable source powers dc micromotors
The circuit in Figure 1 is a simple, economic, compact, and tricky way of using the LM723 as a programmable voltage source to drive dc micromotors. Because of the µPs` accurate positioning and control, these motors are useful in applications such as optical mounts and flexible shaft control, which take advantage of the higher speed and fast...
The purpose of a motor speed controller is to take a signal representing the demanded speed, and to drive a motor at that speed. The controller may or may not actually measure the speed of the motor. If it does, it is called a Feedback Speed Controller or Closed Loop Speed Controller, if not it is called an Open Loop Speed Controller. Feedback...
Motor controller operates without tachometer feedback
Speed controllers have long exploited the reverse-EMF characteristics of dc motors to control their speed. These linear driver circuits use power op amps to create a negative resistance drive to the motor that counteracts the voltage drop in the motor`s series resistance (Reference 1). The circuit in Figure 1 shows an implementation of this type...
Motor-control scheme yields four positions with two outputs
Figure 1 shows how to position a mechanical device into four discrete positions but with only two free outputs and one free input from the control system. The position depends on a set of cams and four corresponding limit switches. The 24V-dc motor comes with a worm gear. Darlington transistors Q3 to Q6 and resistors R7 to R12 form an H-bridge...
H bridge switch for small motors
Two inputs, A and B, control the bridge. With both high (or open circuit) both ends of the motor are connected to 0v. Connect A low and Tr2 turns on causing the motor to go forward. Connect B low and Tr6 turns on, reversing the motor. If A and B are both low, both ends of the motor are high, so the motor is off.
PWM DC Motor Speed Control
This is a circuit for controlling the speed of small DC motors, it works nicely as a speed controller for an HO or N gauge model railroad.
PWM Motor Speed Controller
A pulse width modulator (PWM) is a device that may be used as an efficient light dimmer or DC motor speed controller. The circuit described here is for a general purpose device that can control DC devices which draw up to a few amps of current. The circuit may be used in either 12 or 24 Volt systems with only a few minor wiring changes. This...
PWM Motor/Light Controller
These two schematics are variations on another PWM circuit that I designed. The diagrams are for 12V operation only and there are high side (common ground) and low side (common +12V) versions. The low side version of the circuit uses an N Channel FET, the high side version of the circuit uses a P Channel FET. N Channel devices tend to handle...
Computer fan speed tacho out circuit
You will find this identical circuit inside most 3 wire computer fans with speed monitoring output to the motherboard. Peel off the sticker from the fan hub in order to access a motor winding pin for connecting up the tacho circuit.
ELECTRONIC MOTOR STARTER
This motor starter protects singlephase motors against voltage fluctuations and overloading. Its salient feature is a soft on/off electronic switch for easy operation.
Two Wire Stepper Motor Positioner
Figure 2 is a diagram of the control circuit built on a 1.45 X 1.8 inch PC board. IC1 is an LMC555 CMOS timer that generates a 200 microsecond wide clock pulses to step the motor and control its speed. The speed can be varied by changing the pulse repetition rate with R1.
USING LIGHT DIMMER AS A AC MOTOR SPEED CONTROL
An electronic speed control for an AC Motor can be designed with a Light Dimmer IC by limiting the minimum firing angle of the triac so that the motor wont stall. This can be done effectively for high volume applications by making a minor change to the IC. An alternative to modifying the IC is illustrated in Figure 2.
WASHING MACHINE MOTOR CONTROLLER
Washing machines usually employ a single-phase motor. In semiautomatic washing machines, a purely mechanical switch controls the timing and direction of the motor. These switches are costly and wear out easily.
Step Motor Controller
This application note describes how to implement a compact size and high-speed interrupt driven step motor controller. Step motors are typically used in applications like camera zoom/film feeder, fax machines, printers, copying machines, paper feeders/ sorters and disk drives. The high performance of the AVR controller enables the designer...
SMBus Fan Speed Controller
Battery run times for notebook computers and other portable devices can be improved and acoustic noise reduced by using Linear Technologys LTC®1695 to optimize the operation of these products internal cooling fans. The LTC1695 comes in a SOT-23 package and provides all the functions necessary for a system controller or microcontroller to...
Fan Control Ensures Continuous System Cooling
Figure 1 shows a block diagram for a fan speed control system using the LTC1840. The LTC1840 contains two current DACs used to gain full control over fan speed. The scaled currents individually adjust the fan-driving output voltage of a switching regulator.
INFRARED TOY CAR MOTOR CONTROLLER
This add-on circuit enables remote switching on/off of battery-operated toy cars with the help of a TV/ video remote control handset operating at 3040 kHz. When the circuit is energised from a 6V battery, the decade counter CD4017 (IC2), which is configured as a toggle flip-flop, is immediately reset by the power-onreset combination of...
DC MOTOR CONTROL USING A SINGLE SWITCH
This simple circuit lets you run a DC motor in clockwise or anti-clockwise direction and stop it using a single switch. It provides a constant voltage for proper operation of the motor. The glowing of LED1 through LED3 indicates that the motor is in stop, forward rotation and reverse conditions, respectively.
Speed Controller with PIC16F84-04/SO
The controller is a prototype and works well in my plane with 7 cells and a Graupner-Speed 600.
Motor Speed control with optocoupler
For normal use it`s necessary to connect the battery, when the jumper is connected. Please take care, that the transmitter is on and the throttle is set to "power off".
motor Speed Control
Controller for brushless and sensorless motors, with active rpm control # Active rpm control # Car mode # Proportional brake # Active freeweehling # Updates via Internet available
Speed controller 2
No description available.
Butterfly Mixer Circuit
If the transmitter stick-potentiometer delivers a voltage about 2 - 3 V, this circuit will be suitable. If you want to avoid using the battery cable (supplying Vcc for IC1and -2), you can use a separate 5V supply for IC1 and -2. In that case you should test the mixer function when the battery voltage is low.
Curtain Control Circuit
This hybrid circuit uses a mixture of transistors, an IC and a relay and is used to automatically open or close a pair of curtains. Using switch S3 also allows manual control, allowing for curtains to be left only partially open or closed. The circuit controls a motor which is attached to a simple pulley mechanism, to move the curtains. I first...
Motor Speed Controller
The circuit described here is for a general purpose device that can control DC devices which draw up to a few amps of current. The circuit may be used in either 12 or 24 Volt systems with only a few minor wiring changes. This device has been used to control the brightness of an automotive tail lamp and as a motor speed control for small DC fans...
PWM DC Motor Controller PIC 12F683
A variable resistor provides a voltage input to the PIC which is converted to a digital value using the onboard Analogue to Digital convertor, this in turn is used to set the PWM duty cycle. Since the PWM duty cycle is adjusted using a voltage signal input to the PIC it is possible to use an alternative analogue front-end instead of VR1 to...
Controlling Stepper Motor with a Parallel Port
This is an easy to build stepper motor driver that will allow you to precisely control a unipolar stepper motor through your computer`s parallel port. With a stepper motor you can build a lot of interesting gadgets such as robots, elevator, PCB drilling mill, camera panning system, automatic fish feeder, etc. If you have never worked with...
DC motor PWM speed control
The 555 Ic is wired as an astable and the frequency is constant and independent of the duty cycle, as the total resistance (R charge + R discharge, notice the diode) is constant and equal to 22Kohm (givin a frequency of about 1Khz, notice the hum). When the potentiomenter is all up, the Rcharge resistance is 1,0 Kohm (the diode prevents the...
Auto 12V Fan Controller
Transistor Q1 can be a 2N2222(A), 2N3904, NTE123A, ECG123A, etc. Not critical at all. It acts only as a switch for the relay so almost any type will work, as long as it can provide the current needed to activate the relay's coil. D1, the 1N4148, acts as a spark arrestor when the contacts of the relay open and eliminates false triggering. For my...
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