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H-Bridge. The H-Bridge is designed to drive a motor clockwise and anticlockwise. To reverse a motor, the supply must be reversed and this is what the H-Bridge does. An H-Bridge can be made with SWITCHES, RELAYS, TRANSISTORS or MOSFETS. Note: Some circuits are just demonstration circuits and need "damper diodes" (protection diodes) to reduce spikes. H-Bridge with switches: Do not make circuit "A. " It can easily create a SHORT-CIRCUIT. Switch A and D will make the motor rotate clockwise. An improved design is shown in Circuit C. H-Bridge with a relay: The top diagram shows the underside of a double-pole double-throw relay The motor is active at all times. H-Bridge with 2 relays: This circuit has an advantage. The first two circuits above are manual. THE MOTOR The type of motor we will be powering is a 3-pole (or 5-pole) with two brushes, similar to the following images: These motors come in different shapes and sizes and have an output from 2,000RPM to more than 16,000RPM.

How to Build a Delay Before Turn On Circuit with a 555 Timer. In this circuit, we will show how to build a delay before turn on circuit with a 555 timer chip. A delay before turn on circuit is a circuit that once you apply power to it doesn't turn on the output right away. There is a delay before the output turns on. For this circuit, it's a few seconds delay. Once these few seconds pass, then the output turns on. A delay circuit can be useful for any circuit that needs a delay before output turn on.

How we achieve the delay effect is through the use of a capacitor. Components Needed 555 Timer Chip47KΩ resistor100μF capacitor470Ω resistorLED The 555 timer can be obtained very cheaply from pretty much any electronic retailer. The 555 timer is an 8-pin chip. The pinout of the 555 timer is shown below. The 555 timer requires a power supply voltage of 4.5-16V. The only other pins we use are the trigger pin, the output pin, the reset pin, and the threshold pin. Pin 2 is the trigger pin. Pin 3 is the output pin. 555 timer's output is digital in nature. Flashing L.E.D. Using 555 Timer - All. CAUTION !!! This project contains small parts which can be ingested or inhaled, so keep away from young children.

Make sure to push all the parts in to the breadboard that they make contact with it. 1. Place the 555 Timer chip in the middle of the breadboard, make sure to put it in the right way round other wise when you will connect the battery the chip will burn. 2. Using short length of jump wire connect Pin 1 (negative) to the bottom row of the breadboard (ground). 3. 4. 5. 6. 7. 8. 9. 10. 11. How to Connect a Voltage Regulator in a Circuit. In this article, we go over how to connect a voltage regulator to a circuit to get a specific DC output regulated voltage. Depending on the voltage regulator in use, we can get a regulated positive or negative voltage, at whichever voltage we want. The LM78XX voltage regulators are a popular kind for regulating and outputting positive voltage, while the LM79XX are a popular series of regulators for negative voltage.

In this article, we use a positive voltage regulator, which outputs 5V, the LM7805 regulator. Before we can hook up the circuit, let's first go over the pinout diagram of the voltage regulator, which is vital for hooking up the circuit. A voltage regulator is a 3-terminal device. Pin 1 is the Input Pin. Pin 2 is Ground. Pin 3 is the Output Pin. Okay, now let's build the circuit. Components Needed LM7805 Voltage Regulator Chip9-volt Battery 0.33uF Ceramic Capacitor0.1uF Ceramic Capacitor1KΩ ResistorLED If you don't have all the parts, just follow along. Related Resources. Logic NOT Gate Tutorial with Logic NOT Gate Truth Table.

It is a single input device which has an output level that is normally at logic level “1” and goes “LOW” to a logic level “0” when its single input is at logic level “1”, in other words it “inverts” (complements) its input signal. The output from a NOT gate only returns “HIGH” again when its input is at logic level “0” giving us the Boolean expression of: A = Q.

Then we can define the operation of a single input digital logic NOT gate as being: “If A is NOT true, then Q is true” Transistor NOT Gate A simple 2-input logic NOT gate can be constructed using a RTL Resistor-transistor switches as shown below with the input connected directly to the transistor base. The transistor must be saturated “ON” for an inverted output “OFF” at Q. Logic NOT Gates are available using digital circuits to produce the desired logical function. The Logic NOT Gate Truth Table The “bubble” (o) present at the end of the NOT gate symbol above denotes a signal inversion (complementation) of the output signal. Transistor relay with NO and NC? - Viewing All ACTIVE Comments. How to Build an LED Flasher Circuit with a 555 Timer Chip. In this project, we will show how to build a simple LED flasher circuit using a 555 timer chip.

An LED flasher circuit is a circuit which flashes the LED- meaning turns it ON-OFF, ON-OFF, ON-OFF. The 555 timer chip is a very versatile IC, because when connected correctly, it can it can create pulses of current at specific time intervals decided by the resistor-capacitor (RC) network. When a 555 timer creates pulses in this way, the LED doesn't stay constantly on. It only turns on at a pulse and then shuts off after the pulse has passed. To make the 555 timer chip create pulses, it must be placed in astable mode. To create an LED flasher circuit, the parts which we need to do so are: Components Needed 555 timer IC9-volt Battery or DC power supplyRed LED2 1KΩ Resistors10KΩ Resistor10µF electrolytic capacitor0.01µF ceramic capacitorSeveral jumper wires LED Flasher Circuit The schematic diagram of the LED flasher circuit we will build is shown below: Thigh= 0.7 * (R1 + R2) * C1 Tlow= 0.7 * R2 * C1.