Calculating Re and Ib for Transistor Saturation Region

  • Thread starter Thread starter kliker
  • Start date Start date
  • Tags Tags
    Transistor
Click For Summary
SUMMARY

The discussion focuses on calculating the emitter resistor (Re) and base current (Ib) for a transistor operating in the saturation region. Given parameters include Rc = 2kΩ, R1 = 2kΩ, EB = 5V, Vcc = 10V, V1 = 3V, and β = 100. The calculated value of Re is determined to be 0.86 kΩ based on the assumption that the collector current (Ic) equals the emitter current (Ie). The user is advised to apply Kirchhoff's laws to accurately account for the currents and voltages in the circuit, particularly considering the effects of Vcc and V1 on Re.

PREREQUISITES
  • Understanding of transistor operation in saturation region
  • Familiarity with Kirchhoff's laws
  • Basic knowledge of Ohm's law
  • Ability to analyze simple resistor networks
NEXT STEPS
  • Study the application of Kirchhoff's voltage law in transistor circuits
  • Learn how to calculate base current (Ib) in transistor circuits
  • Explore the effects of varying resistor values on transistor performance
  • Investigate the role of β (beta) in transistor current calculations
USEFUL FOR

Electronics students, circuit designers, and engineers working with transistor circuits, particularly those focusing on saturation region analysis and current calculations.

kliker
Messages
102
Reaction score
0
[PLAIN]http://img256.imageshack.us/img256/2164/transistor.jpg

i should find Re so that transistor works in saturation region

also i should find Ib in saturation region

Rc=2kΩ , R1=2kΩ , EB=5V, Vcc=10V, V1=3V, β=100

im really confused with R1 and V1 i don't know what is their function

i know that in saturation region Vce = 0

also from the diagram i can see that

Eb - 0.7 = Vre so Vre = 4.3 Volts

Ie = Vre/Re

if we assume that Ie = Ic

then

Ic = Vre/Re

Ic is Vcc/Rc = 10/2000 = 5mA

so Re should be Vre/5mA = 4.3/5*10^-3 = 0.86 KΩ

but does this Re stand for saturation region?
 
Last edited by a moderator:
Physics news on Phys.org
Your calculation for Ie doesn't take into account current flowing due to Vcc or V1 in the resistor Re. Use Kirchoff's laws.
 
we have

Eb - 0.7 = Ic1*Re we find Ic1 from Eb

Vcc - Ic(Rc+Re) - Vce = 0
V1 - Ic(R1+Re) - Vce = 0

we find Vce from these two statements and Ic which I will have to add Ic1?

and how can this help me solve the problem?
 

Similar threads

Replies
68
Views
7K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
4
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
4K
Replies
3
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
Replies
12
Views
3K
Replies
5
Views
6K
  • · Replies 1 ·
Replies
1
Views
2K