How do you make a voltage comparator in a circuit?
To create a voltage comparator that creates a positive voltage output if the input voltage is less than a reference voltage, apply the reference voltage to the inverting (V–) input, and the input voltage is applied to the noninverting (V+) input.
Which type of biasing is required to a NPN transistor for amplification?
NPN Transistor Amplifier Working Both forward and reverse bias are needed for the operation of a transistor amplifier.
What is the primary difference between the NPN and PNP amplifiers?
| Difference Between NPN and PNP Transistor | |
|---|---|
| NPN | PNP |
| The current flows from collector terminal to emitter terminal. | The current flows from emitter to collector terminal. |
| One P-type semiconductor is sandwiched between the two N-type semiconductors. | It is made of up two P-type material layers with N-type sandwiched between them. |
Can a circuit be used as a comparator?
The circuit is a comparator and can be remarkably useful more or less as shown. I have used a circuit essentially the same as that in production equipment to meet a requirement which was difficult to meet easily and cheaply by other means. There are several ways to look at the circuit.
How to increase the current of a transistor?
Imagine that Vb1 = Vb1 and > Re such that current Ie divides in 2 equally (as transistors are matched) and Ie/2 flows in each transistor. Vc1 = Vc2 as resistors and currents are equal. Now increase Vb1 slightly. Q1 draws more current by say dIe. But as total current is constant Q2 must decrease current by dIe.
How are bases and transistors used in a circuit?
Transistors were not matched and bases had no resistors to ground – the 2 x 1M acted as current sources and each transistor in turn got less or more drive. This was an extreme case – but the circuit is useful elsewhere.
Which is the correct comparator for IB _ q1 x beta Q1?
It can easily be arranged that Q1 saturates as Ib_Q1 x beta_q1 is > Ie. At this stage Q1 takes all the current, Q1 is turned hard on and Q2 turns off and Vc2 rises to Vcc. A surprisingly effective comparator can be achieved.