Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic 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.

Register Log in

question about NPN match

Status
Not open for further replies.

borislee

Junior Member level 3
Joined
Jul 19, 2005
Messages
25
Helped
2
Reputation
4
Reaction score
0
Trophy points
1,281
Activity points
1,495
Which of following matchs best to a singal NPN transistor with the relationship of 1:N? And which one is the worst?
1. n NPN transistors. In layout, the n transistors can be put together and beside the signal transistor, but cannot put around the singal one.
2. a NPN transistor, with n emitters. Each emitter and the base, the collector has the same area to the corresponding area of the singal transistor.
3. a NPN transistor, the area of the emitter is n times of that of the singal transistor.
 

jwfan

Member level 4
Joined
Nov 13, 2005
Messages
70
Helped
5
Reputation
10
Reaction score
2
Trophy points
1,288
Location
Earth
Activity points
1,741
I prefer the first one. But if the layout budget is limited, the second one.
 

borislee

Junior Member level 3
Joined
Jul 19, 2005
Messages
25
Helped
2
Reputation
4
Reaction score
0
Trophy points
1,281
Activity points
1,495
Thanks to jwfan

would you please explain your answer? I am not familiar with bipolar process.
 

sunking

Advanced Member level 3
Joined
May 25, 2004
Messages
874
Helped
70
Reputation
140
Reaction score
23
Trophy points
1,298
Activity points
6,283
the first one have the same Rbe
 

huojinsi

Full Member level 5
Joined
Jan 21, 2005
Messages
256
Helped
25
Reputation
50
Reaction score
6
Trophy points
1,298
Activity points
2,216
The first one is my preference. The reason is all the transistor's shape and size is same, so the characteristic of every transistor is almost same, and the consistence and symmetry is very good to match, but it occupys many area.
 

borislee

Junior Member level 3
Joined
Jul 19, 2005
Messages
25
Helped
2
Reputation
4
Reaction score
0
Trophy points
1,281
Activity points
1,495
thanks to sunking and Huajinsi

And how about the second choice and the last one? which one is better and why?
 

marshel

Member level 2
Joined
Jun 10, 2005
Messages
46
Helped
7
Reputation
14
Reaction score
3
Trophy points
1,288
Location
China
Activity points
1,687
Compared to the 2nd and the 3rd, the 2nd is better. For the 2nd have the same ratio of area and perimeter of emitter base and collector.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top