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	62448
공지	메모	연락처 목록	모아레	2010.08.05	41027
공지	메모	유용한 사이트	모아레	2010.02.25	53544
공지	메모	메모 정리 (미완)	모아레	2009.10.30	48367
공지	메모	연구실 장비 목록	모아레	2009.09.30	42252
공지	메모	주문, 구입 리스트	모아레	2009.09.21	51635
공지	메모	To do list, Short Memo	모아레	2009.08.20	32565
72	자료	물질안전보건자료(MSDS)란?	모아레	2009.08.28	13679
71	메모	Evaporation, LIft off	모아레	2009.09.02	23230
70	자료	그라핀	모아레	2009.09.02	19869
69	메모	Coating, SEM 사용, Wet Etching 과정 정리	모아레	2009.09.03	15762
68	메모	Keywords	모아레	2009.09.11	14493
67	기타	Georgia Institute of Technology - Wang Group	모아레	2009.09.11	17302
66	자료	오실로스코프의 이해와 올바른 사용법	모아레	2009.09.13	13877
65	메모	Endnotes 학교에서 다운받는 곳	모아레	2009.09.17	19514
64	메모	Temperature controller & heater	모아레	2009.09.18	14208
63	메모	클린룸 관련 사이트	모아레	2009.09.21	20073
62	메모	메일서버 접속문제 해결	모아레	2009.09.25	21139
61	자료	Hall effect	모아레	2009.09.26	15113
60	메모	청계천 구입 리스트	모아레	2009.10.12	17675
59	기타	Lieber Appointed Coeditor Of Nano Letters	모아레	2009.10.26	22123
58	자료	나노 재료에서의 screening effect	모아레	2009.10.30	14609
57	메모	SMA connector specification	모아레	2009.10.30	13639
56	메모	회식 자리 모음	모아레	2009.11.07	26021
55	메모	연구실 서버를 위한 리눅스 관리 가이드	모아레	2009.11.10	27181
54	메모	9월9일 구입한 컴퓨터 사양	모아레	2009.11.24	15095
53	메모	JDH's Double Shuttle conditions 1	모아레	2009.12.03	21657

분류

글쓴이

공지

회사 목록