Question: Can A Transistor Be Obtained By Connecting Two Semiconductor Diodes Back To Back?

Can we replace transistor by two back to back connected diodes?

Once a metal introduced in this path (which is what two back-to-back diodes represent) , no BJT functionality is possible.


Two back to back diodes is NOT a transistor.

The special property that makes a PNP or NPN sandwich a transistor rather than just two diodes is that the base layer is very thin..

Can a transistor be made from two diodes?

You just can’t. There’s a transistor-model which is explained with two diodes and you can measure the two diodes in the transistor but you cannot make a transistor with two diodes. … The assymetrical doping of collector and emitter and the very thin shared base differs the real transistor from your diodes.

Can we use transistor as diode?

Since a bipolar transistor is essentially two diodes, it can function as such. However, since bipolar transistors are not designed to be used as diodes, using them as diodes might cause a problem in terms of current and other ratings. … Use dedicated diodes for typical diode applications instead of bipolar transistors.

Why transistor is not used as rectifier?

Since base is thin one and lightly doped, either of the two segment does not work properly as p-n junction diode, which is required for a rectifier. … That is why, a transistor can not be used as a rectifier.

What happens when diodes are connected in series?

Diodes are connected together in series to provide a constant DC voltage across the diode combination. The output voltage across the diodes remains constant in spite of changes in the load current drawn from the series combination or changes in the DC power supply voltage that feeds them.

What are diodes and transistors?

Put simply, a diode is a two-terminal semiconductor device and a transistor is a three-terminal semiconductor device. A diode can allow the flow of current in one direction while blocking the flow of current in the other direction.

What is transistor action?

So in a NPN Transistor it is the movement of negative current carriers (electrons) through the Base region that constitutes transistor action, since these mobile electrons provide the link between the Collector and Emitter circuits.

Can two pn junction diodes placed back to back work as PNP transistor?

In other words the emitter/base current flow draws some of the barrier charge away from the collector/base junction and allows collector/emitter current to flow across the base using minority carriers. … So transistor action is not possible.

What happens when two diodes are connected in parallel?

Diodes connection in parallel do not share the current equally due to different forward bias characteristics. The diode with the lowest forward voltage drop will try to carry a larger current and can overheat. … If these two diodes are connected in parallel at a given voltage, a different current flow in each diode.

Do diodes have a resistance?

Just like a resistor or any other load in a circuit, a diode offers resistance in a circuit. Unlike resistors, though, diodes are not linear devices. This means that the resistance of diodes does not vary directly and proportional to the amount of voltage and current applied to them. It changes parabolically.

What happens if you put a diode in backwards?

Voltage connected to the diode in this direction is called forward bias. But if you reverse the voltage direction, applying the positive side to the cathode and the negative side to the anode, current doesn’t flow. In effect, the diode becomes an insulator. … Reverse bias doesn’t allow current to flow.

Which is the most commonly used transistor configuration Why?

Common emitter transistor configuration Both current and voltage gain can be described as medium, but the output is the inverse of the input, i.e. 180° phase change. This provides a good overall performance and as such it is often the most widely used configuration.