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.

Current mirror - stacked pairs of NPN

Status
Not open for further replies.

Prototyp_V1.0

Advanced Member level 2
Advanced Member level 2
Joined
Apr 3, 2007
Messages
673
Helped
119
Reputation
238
Reaction score
83
Trophy points
1,308
Location
Norway
Activity points
5,104
Hi.

Reading this thread, I found a sort of current mirror.

I've uploaded a cropped version of the circuit in the referred thread.

What I don't quite understand is the working of the circuit. Is this circuit expected to have better characteristics than a circuit with only two NPN's?

thanks :)
 

Attachments

  • curentmirror_crop.jpg
    curentmirror_crop.jpg
    7.4 KB · Views: 141

This is a piece of something bigger, it looks like a PTAT
or an attempt to produce a tempco that differs from
the bias current. The key is VBE vs VBE+I*R at the
bottom, the rest is just cascode shields.
 

VBE_Q810=VBE_Q800+I*R
VBE_Q810-VBE_Q800=VT*ln4 if they have matched current.
A current mirror is needed at the high end.
 

VBE_Q810=VBE_Q800+I*R
VBE_Q810-VBE_Q800=VT*ln4 if they have matched current.
A current mirror is needed at the high end.
I understand that as that circuit alone isn't useful for anything?
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top