OBG Home - how to confirm the impedance of the microstrip?

mckinson

Joined: 03 Sep 2003
Posts: 136

28 Nov 2004 15:24 Hello ,about the 50 ohms microstrip !

Hello ,guys . Anybody knows how to confirm the impedance of the microstrip ?
For example ,I have simulated the width of the microstrip for 50 homs .But I don't
know whether the impedance of pcb tracks from pcb manufactory is correct ? How to confirm ? Best regards !

Google
AdSense
Google Adsense

http://www.edaboard.com/ftopic98986.html

28 Nov 2004 15:24 Ads

BigBoss

Joined: 17 Nov 2001
Posts: 1177
Helped: 89
Location: Earth

28 Nov 2004 18:38 Re: Hello ,about the 50 ohms microstrip !

mckinson wrote:

Connect an 50 Ohm low ESR and inductance resistor (or 2 parallel 100 Ohm) at the end of line and measure with VNA.

vfone

Joined: 10 Oct 2001
Posts: 2578
Helped: 358

28 Nov 2004 22:45 Re: Hello ,about the 50 ohms microstrip !

You don’t need any extra components. Just measure with Network Analyzer, that is connected at both ends of the line.

sergio mariotti

Joined: 22 Dec 2003
Posts: 469
Helped: 43
Location: Italy

29 Nov 2004 0:03 Re: Hello ,about the 50 ohms microstrip !

vfone wrote:

You dont need any extra components. Just measure with Network Analyzer, that is connected at both ends of the line.

Yes, correct, but usually it may be experimented that measured Zo differ a lot from the simulated one, also in the case that all is correct and well manufactured.
This is due to end effects and ľstrip launchers.
To reduce this effect and focalize the attention to the line only, use a Time Domain VNA. Both Agilent and Anritsu have very efficent and useful TD algoritms.

mckinson

Joined: 03 Sep 2003
Posts: 136

29 Nov 2004 16:14 Hello ,about the 50 ohms microstrip !

Appreciated !Do you think that is accurate measure the character impedance Z0 by the VNA ?
Could you please tell me the detail stap for measurement ? Best regards !

vfone

Joined: 10 Oct 2001
Posts: 2578
Helped: 358

29 Nov 2004 17:59 Re: Hello ,about the 50 ohms microstrip !

By definition the main designation of VNA is to measure impedances.
Time Domain Reflectometry (TDR) is more accurate than frequency domain Vector Network Analysis (VNA), because do not depend by frequency.
But for commercial applications frequency domain is more than ok.
Check this document:
http://cp.literature.agilent.com/litweb/pdf/5968-1947E.pdf

hitmo

Joined: 04 Jan 2005
Posts: 40

13 Jan 2005 18:55 Re: Hello ,about the 50 ohms microstrip !

u can also do it with network ana. just measure inserstion loss and return loss on smith chart. return loss will tell u the impedance of the line. if the rerunloss is as close as possible to center of the smith chart its a 50ohm line

List of Articles
번호	분류	제목	글쓴이	날짜	조회 수
공지		회사 목록	모아레	2011.02.07	19189
공지	메모	연락처 목록	모아레	2010.08.05	377
공지	메모	유용한 사이트	모아레	2010.02.25	5848
공지	메모	메모 정리 (미완)	모아레	2009.10.30	247
공지	메모	연구실 장비 목록	모아레	2009.09.30	940
공지	메모	주문, 구입 리스트	모아레	2009.09.21	547
공지	메모	To do list, Short Memo	모아레	2009.08.20	519
32	메모	Vacuum Can Leak Problem	모아레	2010.01.04	138
31	메모	Developers (MIF, MIC)	모아레	2010.08.13	136
30	메모	메일서버 접속문제 해결	모아레	2009.09.25	135
29	메모	윈도우2003 프린터 공유 문제 해결	모아레	2010.02.10	133
28	자료	Coplanar Waveguide	모아레	2010.01.31	132
27	메모	Gordon Research Conference	모아레	2010.02.21	131
26	메모	BOE, Silox 에칭 테스트 과정	모아레	2010.01.25	129
25	메모	JDH's Double Shuttle conditions 1	모아레	2009.12.03	128
24	메모	Temperature controller & heater	모아레	2009.09.18	128
23	메모	클린룸 관련 사이트	모아레	2009.09.21	126
22	자료	Network Analyzer	모아레	2010.08.11	125
21	메모	Coating, SEM 사용, Wet Etching 과정 정리	모아레	2009.09.03	124
20	메모	9월9일 구입한 컴퓨터 사양	모아레	2009.11.24	124
19	메모	NPGS for SEM Lithography	모아레	2009.08.07	122
18	메모	회식 자리 모음	모아레	2009.11.07	121
17	메모	옥스포드 트랜스포트 튜브 거는 것 관련	모아레	2009.07.28	121
16	메모	Endnotes 학교에서 다운받는 곳	모아레	2009.09.17	120
15	자료	COMSOL 시뮬레이션 참고자료	모아레	2009.07.30	119
14	메모	청계천 구입 리스트	모아레	2009.10.12	113
13	메모	MEMS 관련 PDF 문서	모아레	2010.02.17	113

분류

글쓴이

공지

회사 목록