Contents
What are diodes and transistors used for?
The diode is used for converting the AC to DC or for rectifications whereas the transistor is mainly used for amplification and as a regulator. The diode has two terminals namely anode and cathode. The anode is the positive terminal, and the cathode is the negative terminal of the diode.
What is transistor and diode?
The main difference between diode and transistor is that a diode is a two terminal device which allows current in one direction only from the anode to the cathode. On the contrary, a transistor is a three terminal device which passes current from high resistance region to low resistance region.
How does a diode transistor work?
A transistor works when the electrons and the holes start moving across the two junctions between the n-type and p-type silicon. The small current that we turn on at the base makes a big current flow between the emitter and the collector. We can also understand a transistor by thinking of it like a pair of diodes.
Why do you need a soft start circuit?
A Soft Start Circuit prevents the sudden current flow in the circuit during the start. It slows down the rate of rising output voltage by minimizing the excess current flow during the start. It is useful to protect the devices or electronic components from the damage caused by instantaneous high input current.
What kind of regulator is used in soft start circuit?
Some components which are current limited and having poor load regulation can get damaged because of this high input current. Here we are building the soft start circuit using a voltage regulator IC LM317 and a PNP transistor BC557. It’s an adjustable three-terminal voltage regulator IC, with a high output current value of 1.5A.
What does the output voltage of a transistor do?
As you can see the output voltage is basically a flat line. In your circuit the diode add a polarity inversion protection, so you will see a lower voltage, according to the current supplied.
What happens if you don’t have a diode in a transistor?
Without the diode, the voltage across the motor would get as large as necessary to keep the current flowing, which would probably require frying the transistor.