The H-bridge is a circuit used in electronic control of high current devices, particularly where the device polarity may be reversed, e. g. DC motors. The name comes from the fact that the circuit typically looks like a letter `H`. The circuit shown has four switches and a motor. To apply a voltage across the motor a pair of diagonally opposite swi
Click here to download the full size of the above Circuit.
tches need to be turned on. Depending on which pair of switches are turned on the motor will turn one way or another. If both the top or both the bottom switches are turned on the motor will have no voltage difference across it so it won`t move at all. If the top and bottom switches on one side are turned on together by accident we will short out the supply, so you need to be careful if you`re building your own H-bridge. Most pre-packaged ones will have internal logic to prevent this. You can build an H-bridge like this out of relays instead of switches and control them with a lower current to drive big motors but most often the switches are replaced with transistors, a pair of PNP transistors (or p-type MOSFETS) at the top and a pair of NPN (or n-type MOSFETS) at the bottom. PWM is a method of digitally controlling an output with a variable equivalent voltage. Essentially if you take the average of the signal over time then it has a varying analog level, however in the short term it is digital. This makes it easy to generate and efficient as transistors are most efficient when on or off rather than partially conducting. Most modern microcontrollers have the ability to generate PWM built in, including the Arduino and derivatives. To control a plain H-bridge you need 4 signals to control the 4 transistors, to control it with PWM you need two PWM signals and two plain digital signals. You could theoretically use just the two...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
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....
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....
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....
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....
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,....
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....
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....
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.....
characters left: