A Zener diode, having a breakdown voltage equal to 15 V, is used in a voltage regulator circuit as shown in the figure. The current through the diode is:
1. 5 mA
2. 10 mA
3. 15 mA
4. 20 mA
In the following figure, the diodes which are forward biased are:
(a) | |
(b) | |
(c) | |
(d) |
1. (a), (b) and (d)
2. (c) only
3. (a) and (c)
4. (b) and (d)
Pure Si at \(500~\text{K}\) has an equal number of electron \((n_e)\) and hole\((n_h)\) concentrations of \(1.5\times10^{16}~\text{m}^{-3}\). Doping by indium increases \(n_h\) to \(4.5\times10^{22}~\text{m}^{-3}\). The doped semiconductor is of:
1. | \(p\)-type with electron concentration \(n_e=5\times10^9~\text{m}^{-3}\) |
2. | \(n\)-type with electron concentration \(n_e=5\times10^{22}~\text{m}^{-3}\) |
3. | \(p\)-type with electron concentration \(n_e=2.5\times10^{10}~\text{m}^{-3}\) |
4. | \(n\)-type with electron concentration \(n_e=2.5\times10^{23}~\text{m}^{-3}\) |
The following figure shows a logic gate circuit with two inputs A and B, and the output Y. The voltage waveforms of A, B and Y are as given.
The logic gate is:
1. OR gate
2. AND gate
3. NAND gate
4. NOR gate
To get output \(Y = 1\) in the given circuit which of the following input will be correct?
\(A\) | \(B\) | \(C\) | |
1. | 1 | 0 | 1 |
2. | 1 | 1 | 0 |
3. | 0 | 1 | 0 |
4. | 1 | 0 | 0 |
The following table is for which logic gate?
Input | Output | |
A | B | C |
0 | 0 | 1 |
0 | 1 | 1 |
1 | 0 | 1 |
1 | 1 | 0 |
1. AND
2. OR
3. NAND
4. NOT
The following logic gate is:
1. AND
2. NAND
3. EX-OR
4. OR
One part of a device is connected to the negative terminal of a battery and the other part is connected to the positive terminal of a battery. If their ends are now altered, current does not flow in circuit. The device is:
1. P-N Junction
2. Transistor
3. Zener diode
4. Triode
Zener diode is used for:
1. rectification.
2. stabilisation.
3. amplification.
4. producing oscillations in an oscillator.
From the following diode circuit, which diode is in forward biased condition:
1. | 2. | ||
3. | 4. |