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	52070
공지	메모	연락처 목록	모아레	2010.08.05	26989
공지	메모	유용한 사이트	모아레	2010.02.25	40289
공지	메모	메모 정리 (미완)	모아레	2009.10.30	24148
공지	메모	연구실 장비 목록	모아레	2009.09.30	30816
공지	메모	주문, 구입 리스트	모아레	2009.09.21	24826
공지	메모	To do list, Short Memo	모아레	2009.08.20	27053
72	자료	BOE(Buffered oxide etch)	모아레	2010.01.11	10717
71	메모	CNT 성질 연구	모아레	2009.07.08	10686
70	메모	Double Shuttle 제작 관련	모아레	2010.02.09	10682
69	기타	Lieber Appointed Coeditor Of Nano Letters	모아레	2009.10.26	10554
68	메모	MEMS 관련 PDF 문서	모아레	2010.02.17	10516
67	자료	Hall effect	모아레	2009.09.26	10505
66	메모	Gordon conference activity 적은 것	모아레	2010.02.22	10495
65	메모	KPS 초록	모아레	2010.10.02	10477
64	논문	A huge quantum resonator	모아레	2010.03.24	10462
63	메모	BOE, Silox 에칭 테스트 과정	모아레	2010.01.25	10442
62	메모	Evaporation, LIft off	모아레	2009.09.02	10428
61	메모	컴퓨터 오류	모아레	2010.11.15	10376
60	메모	Ashing Test	모아레	2010.05.18	10345
59	메모	SMA connector specification	모아레	2009.10.30	10343
58	자료	Silox Vapox III	모아레	2010.01.11	10342
57	자료	Cryo pump 원리 - 플래시	모아레	2010.05.07	10335
56	메모	About Network Analyzer Calibration	모아레	2010.08.16	10332
55	메모	견적서 내용	모아레	2009.08.03	10254
54	자료	물질안전보건자료(MSDS)란?	모아레	2009.08.28	10212
53	메모	Gordon Research Conference	모아레	2010.02.21	10183

분류

글쓴이

공지

회사 목록