Skip to content
← Electronics

Electronics · 2nd Puc Science

Ch 1Field Effect Transistor (FET) — 2nd PUC Electronics, concept-first.

Every electronics student meets the bipolar junction transistor (BJT) first, where the output current is steered by an input current. The field effect transistor (FET) works on a completely different idea: an electric field set up by a small input voltage widens or narrows a conducting channel and so controls the curre…

Exam weightage:1m × 13m × 1

70

Q&A

15

Concepts

4m

Exam weightage

Start learning — read this chapter →

Key concepts

Hover a concept to preview it and jump to its most relevant Q&A.

Field Effect Transistor (FET)

A three-terminal, unipolar, voltage-controlled semiconductor device whose channel current is set by the electric field from the gate voltage.

Most relevant Q&A

Start with this concept →

Chapter contents

The NCERT structure, section by section. Open a section to see its questions, then read the concept-first solution.

Introduction

Every electronics student meets the bipolar junction transistor (BJT) first, where the output current is steered by an input current.

1.1

Introduction to the Field Effect Transistor

A field effect transistor (FET) is a three-terminal, unipolar solid-state device in which the current is controlled by an electric field.

Chapter Summary

- An FET is a three-terminal, unipolar, voltage-controlled solid-state device; current is controlled by an electric field and carried by majority carriers only.

More questions

70 Q
+Show 32 questions32 questions
  1. Q1What is FET?Free
  2. Q2Expand the term FET.Free
  3. Q3Is FET a current controlled device or a voltage controlled device?Free
  4. Q4Name the terminals of FET.Preview
  5. Q5What are the two main types of FET?Preview
  6. Q6Expand JFET.Preview
  7. Q7Expand MOSFET.Preview
  8. Q8Expand IGFET.Preview
  9. Q9Mention the two types of JFET.Preview
  10. Q10What is an n-channel JFET?Preview
  11. Q11What is p-channel JFET?Preview
  12. Q12How many pn junctions are present in JFET?Preview
  13. Q13What is the function of gate?Preview
  14. Q14Write the symbol of n-channel JFET.Preview
  15. Q15Write the symbol of p-channel JFET.Preview
  16. Q16Is FET a unipolar device or a bipolar device?Preview
  17. Q17Name the charge carrier which is responsible for conduction of current in a n-channel JFET.Preview
  18. Q18Name the charge carrier which is responsible for conduction of current in a p- channel JFET.Preview
  19. Q19Write the function of the source.Preview
  20. Q20What is the function of drain?Preview
  21. Q21Which is the type of potential usually applied to the gate terminal?Preview
  22. Q22What is pinch off ?Preview
  23. Q23What is the value of drain current at pinchoff condition?Preview
  24. Q24Name the two characteristics of JFET.Preview
  25. Q25What is drain characteristics?Preview
  26. Q26What is transfer characteristics?Preview
  27. Q27What is drain resistance?Preview
  28. Q28What is trans conductance?Preview
  29. Q29What is amplification factor?Preview
  30. Q30Write the relation between μ, r_d and g_m.Preview
  31. Q31What is I_DSS?Preview
  32. Q32Write any one characteristic feature of FET.Preview
+Show 6 questions6 questions
  1. Example 1Find the value of the drain resistance given drain-to-source voltage \(V_{DS} = 4\) V and drain current \(I_D = 2\) mA with gate open.Free
  2. Example 2Determine the value of \(I_D\) given \(I_{DSS} = 4\) mA, \(V_{GS} = -2\) V and \(V_P = -5\) V.Free
  3. Example 3Given \(I_D = 10\) mA and \(V_{GS} = -1\) V, determine the value of \(V_P\) if \(I_{DSS} = 20\) mA.Preview
  4. Example 4Given \(g_{mo} = 5\) mS, \(V_{GS} = -2\) V and \(V_P = -3\) V, find the value of \(g_m\).Preview
  5. Example 5If \(V_{DS} = 4\) V and \(V_{GS} = -1\) V, find the value of \(\mu\).Preview
  6. Example 6Given \(r_d = 2\,k\Omega\) and \(g_m = 10\) mS, find the value of .Preview
+Show 5 questions5 questions
  1. Q1The pinch off voltage of FET is \(-3\) V and drain saturation current is 5 mA. If gate to source voltage is \(-2\) V, find the values of dra…Free
  2. Q2Find the value of the drain current if drain resistance \(r_d = 3\,k\Omega\) and drain-to-source voltage is 4 V when the gate terminal is op…Free
  3. Q3The pinch off voltage of FET is \(-3\) V. For a gate to source voltage \(-2\) V drain current is 5 mA. Calculate drain to source saturation…Preview
  4. Q4Find the value of \(\mu\) given \(r_d = 5\,k\Omega\) and \(g_m = 12\) mS.Preview
  5. Q5Find the value of \(g_m\), given \(V_{GS} = -2\) V, \(V_P = -6\) V and \(g_{mo} = 8\) mS.Preview
+Show 16 questions16 questions
  1. Q1Expand the terms FET and MOSFET.Free
  2. Q2Write the circuit symbol of FET and name the terminals.Free
  3. Q3Write the function of drain and gate.Free
  4. Q4Draw the symbols of n-channel JFET and p-channel JFET.Preview
  5. Q5Write any two differences between FET and BJT.Preview
  6. Q6Describe briefly the construction of n-channel JFET.Preview
  7. Q7Describe briefly the construction of p-channel JFET.Preview
  8. Q8Name charge carriers in the current conduction of n-channel and p-channel JFETs.Preview
  9. Q9Explain what happens to the pn junctions when the gate is reverse biased.Preview
  10. Q10What is pinch off ? What is the value of drain current at pinch off ?Preview
  11. Q11Draw the circuit diagram to plot the characteristics of n-channel JFET.Preview
  12. Q12Explain the terms r_d and g_m.Preview
  13. Q13What is amplification factor ? Write its relation with r_d and g_m.Preview
  14. Q14Derive the relation μ = r_d × g_m .Preview
  15. Q15What is I_DSS? Write the relation between I_D, I_DSS, V_GS, and V_P.Preview
  16. Q16What is trans conductance? write the relation between g_m, g_mo, V_GS and V_P.Preview
+Show 5 questions5 questions
  1. Q1Define the terms i. amplification factor, ii. trans conductance and iii. drain resistance.Free
  2. Q2Derive the relation for g_m in terms of V_GS and V_P.Free
  3. Q3Give the comparision between BJT and JFET.Preview
  4. Q4Briefly explain the working of n channel JFET.Preview
  5. Q5Briefly explain how to find r_d and μ from the graph. ![Karnataka PUC Electronics JFET drain characteristics: a family of drain-current I_D…Preview
+Show 6 questions6 questions
  1. Q1Explain the classification of FET and the construction of a n-channel JFET.Free
  2. Q2Distinguish between FET and BJT.Free
  3. Q3Explain the formation of depletion regions formed due to gate potential and also drain-source voltage.Preview
  4. Q4Explain the characteristics of n-channel JFET with a circuit diagram.Preview
  5. Q5Explain the terms I_D, I_DSS, g_m, g_mo and μ .Preview
  6. Q6Derive the relation μ = r_d x g_m and g_m = g_mo [1 - v_GS/v_P]Preview