Calculating BJT Dynamic Parameters with Charge Control Equations

In summary, the conversation discusses the search for a text that thoroughly covers calculation of fall time, rise time, saturation time, and final rise time with examples. The book "Microelectronic Circuit Design" is mentioned but does not provide sufficient information. The topic of calculating these numbers using charge control equations is also brought up, with a suggestion to review the Gummel-Poon model. It is noted that understanding circuit topology and input pulse waveform parameters is also important in determining these digital parameters.
  • #1
kyva1929
18
0
Hi!

Can anyone recommend a text that goes through calculation in fall time, rise time, saturation time and final rise time thoroughly with some examples provided?

I've looked through microelectronic circuit design by Jaeger / Neamen, they briefly mention the concept at best but do not have any examples nor problems that I can work on.

edit: I'm looking for a discussion on how to calculate these numbers by using charge control equations. For example, the delay time can be calculated from relating the average current and the equivalent capacitance in the junction.

Thank you!
 
Last edited:
Engineering news on Phys.org
  • #2
If you want just charge control, review Gummel-Poon model derivations that include the junction capacitance.

Be aware this isn't enough to know any of these digital parameters: circuit topology and input pulse waveform parameters are equal contributors.
 

1. What is the basic principle behind the dynamic behavior of a BJT?

The dynamic behavior of a BJT (Bipolar Junction Transistor) is based on the interaction between minority carriers (electrons and holes) and majority carriers (electrons and holes) in the semiconductor material. When a voltage is applied across the base-emitter junction, it causes a flow of minority carriers from the emitter to the base, resulting in a larger flow of majority carriers from the collector to the emitter.

2. What is the difference between static and dynamic behavior of a BJT?

The static behavior of a BJT refers to its steady-state characteristics, such as the DC current gain and collector-emitter voltage. On the other hand, the dynamic behavior of a BJT refers to its response to changes in input signals, including its frequency response and time-dependent behavior.

3. How does biasing affect the dynamic behavior of a BJT?

Biasing, which involves applying a DC voltage to the base-emitter junction, affects the dynamic behavior of a BJT by establishing the operating point or Q-point. This Q-point determines the amount of base current needed to turn on the transistor and the amount of collector current it can handle in the active region. Biasing also affects the frequency response and stability of the transistor.

4. What is the Miller effect and how does it impact the dynamic behavior of a BJT?

The Miller effect is a phenomenon in which the capacitance between the collector and base of a BJT is amplified due to the voltage gain of the transistor. This results in a higher effective capacitance, which can reduce the high-frequency response and cause instability in certain circuits. Designers must take the Miller effect into account when designing high-frequency BJT circuits.

5. How does temperature affect the dynamic behavior of a BJT?

Temperature can significantly impact the dynamic behavior of a BJT. As temperature increases, the number of minority carriers increases, leading to higher leakage currents and reduced gain. In addition, the thermal energy can cause the transistor to enter thermal runaway, where the collector current increases uncontrollably. Therefore, proper heat dissipation and thermal management are crucial in maintaining the stability and performance of BJTs.

Similar threads

Bernoulli equation and parallel pipe branch
    • Mechanical Engineering
Replies
31
Views
2K
Capacitive touchscreen control using a transistor
    • Electrical Engineering
Replies
4
Views
3K
Calculating Decoupling Capacitor When Datasheets Don't Specify Parameters
    • Electrical Engineering
Replies
4
Views
7K
Trying to build a capacitor charging circuit
    • Electrical Engineering
Replies
14
Views
4K
Calculate Gas Behavior Step-by-Step in Simple Model
    • Mechanical Engineering
2
Replies
43
Views
4K
Complete Noise Analysis: to find the minimum detectable signal
    • Electrical Engineering
Replies
9
Views
2K
Help with design - NPN High Power BJT
    • Electrical Engineering
Replies
13
Views
6K
I Exploring the Flexibility of Coordinates in Euler-Lagrange Equations
    • Mechanics
Replies
5
Views
861
Double experiment: "Falling ball viscometry" and viscous flow in an horizontal pipe
    • Engineering and Comp Sci Homework Help
Replies
31
Views
1K
I Feynmann's connection machine model
    • Differential Equations
Replies
1
Views
695

Hot Threads

Recent Insights

Back
Top