Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

[SOLVED] BJT switching times ( fall time and rise time approximations )

Status
Not open for further replies.

Robotduck

Member level 2
Joined
Feb 10, 2019
Messages
50
Helped
0
Reputation
0
Reaction score
0
Trophy points
6
Activity points
448
Can someone please help me understand the approximations that are made in this attached handout.
In calculation of rise time the Q is assumed to be off but in reality it is in active region ?
Second, in calculation of fall time , Q is assumed to be a constant current source but in reality the current is changing ?

Thank you
 

Attachments

  • 18159E7F-9837-47A0-A369-051AAA970F67.jpg
    18159E7F-9837-47A0-A369-051AAA970F67.jpg
    508.4 KB · Views: 132
  • CC3169A0-E15F-468F-AF07-4DD669B4646F.jpg
    CC3169A0-E15F-468F-AF07-4DD669B4646F.jpg
    508.1 KB · Views: 100

Is it because during Rise time, the BJT is not in true active region ? Because base current is negative.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top