f*****0
发帖数: 489 | 1 impedance matching is rarely required for anything other than rf. in those
cases, you want the prior amp's output impedance to be low and the input
impedance of the next amp to be high. |
|
c***u
发帖数: 843 | 2 现在有一个coplanar waveguide (CPW)，想把他的characteristic impedance做的比较
高（slightly
higher than 50 ohms），尽量minimize conductor loss,所以得把signal和ground之
间的间距做的比
较大，但是因为我们用来测量cpw的picoprobe的pitch比较小，所以在cpw的两端必须要
把这个间距降
低。但是降低间距的话，characteristic impedance就会降低，这样和probe之间就有
了一个
impedance mismatch。
大牛们觉得怎么在减小cpw间距的同时minimize loss？？简单的用一个linear taper可
以吗？
或者有什么文章可以推荐看看的？ 万分感谢！！！ |
|
a****o
发帖数: 298 | 3 @60MHz。6圈的coil，通过6米的线接到signal generator。如果要做impedance
matching，第一步就要先求R&Z。
R的话我就测了6米电线+coil的电阻：0.9欧。
coil的电阻为0，所以Z(coil)=X(coil)。现在再加入一个测试电阻到电路里：U(R)/U(
coil)=R/X(coil)。
我试了几个不用的电阻，得到的X(coil)都不一样，这样的话怎么能够精确的做
impedance matching啊？为什么换不同电阻得到的coil的impedance不一样呢？ |
|
b****g
发帖数: 4933 | 4 ☆─────────────────────────────────────☆
ofarmer (farmer) 于 (Wed Apr 5 21:29:27 2000) 提到:
照葫芦画瓢从网买了Wharfedale Speaker, and Teac Receiver
结果发现：
Speaker--
Nominal Impedance is 4 ohms.
Receiver--
Use the speakers with a nominal impedance of 8 ohms
or more.
Hook up起来以后，我的耳朵听着没有异常。
但想知道这样搭配是不是不好？
☆─────────────────────────────────────☆
yeho (叶子一百一十天) 于 (Thu Apr 6 11:35:58 2000) 提到:
i think it might be OK
☆─────────────────────────────────────☆
uic (blown away) 于 (Thu Apr 6 16:06:00 2 |
|
k*****n
发帖数: 9823 | 5 ☆─────────────────────────────────────☆
ofarmer (farmer) 于 (Wed Apr 5 21:29:27 2000) 提到:
照葫芦画瓢从网买了Wharfedale Speaker, and Teac Receiver
结果发现：
Speaker--
Nominal Impedance is 4 ohms.
Receiver--
Use the speakers with a nominal impedance of 8 ohms
or more.
Hook up起来以后，我的耳朵听着没有异常。
但想知道这样搭配是不是不好？
☆─────────────────────────────────────☆
yeho (叶子一百一十天) 于 (Thu Apr 6 11:35:58 2000) 提到:
i think it might be OK
☆─────────────────────────────────────☆
uic (blown away) 于 (Thu Apr 6 16:06:00 2 |
|
S*****n
发帖数: 6055 | 6 【 以下文字转载自 Chemistry 讨论区 】
发信人: lsl (“以德服人”), 信区: Chemistry
标 题: Re: eBook help: Impedance spectroscopy. Princeton, Columbia,
发信站: BBS 未名空间站 (Thu Apr 24 19:19:31 2008)
http://rapidshare.com/files/3294408/0471647497.rar.html
自己下。
其实很多电子书网上都有的，我搜电子书的方法如下：
1.google
在搜索栏输入书名 空格 然后rapidshare （或者还有一些其他的类似的中转网站，像
megaupload，box，等等），然后点search，像你要的这本书就是用“Impedance
Spectroscopy: Theory, Experiment, and Applications, 2nd Edition rapidshare”
作为google搜索关键词的第一个结果，然后点击进去之后确实有下载链接，就是我上面
给的这个链接，我没有试，你可以试一下
2.che |
|
r**k
发帖数: 111 | 7 果然好用
攒
【 以下文字转载自 Chemistry 讨论区 】
发信人: lsl (“以德服人”), 信区: Chemistry
标 题: Re: eBook help: Impedance spectroscopy. Princeton, Columbia,
发信站: BBS 未名空间站 (Thu Apr 24 19:19:31 2008)
http://rapidshare.com/files/3294408/0471647497.rar.html
自己下。
其实很多电子书网上都有的，我搜电子书的方法如下：
1.google
在搜索栏输入书名 空格 然后rapidshare （或者还有一些其他的类似的中转网站，像
megaupload，box，等等），然后点search，像你要的这本书就是用“Impedance
Spectroscopy: Theory, Experiment, and Applications, 2nd Edition rapidshare”
作为google搜索关键词的第一个结果，然后点击进去之后确实有下载链接，就是我上面
给的这个链接，我没有试，你可以试 |
|
x*******2
发帖数: 5333 | 8 【 以下文字转载自 Physics 讨论区 】
发信人: xmdxx1182 (卡西莫多), 信区: Physics
标 题: 有人懂impedance吗
发信站: BBS 未名空间站 (Fri Apr 8 13:58:18 2011, 美东)
一般镀膜impedance都是显示电容和电阻串联，结果我显示是电感和电阻串联。有人能
指点一下这是为啥吗？ |
|
C*******g
发帖数: 82 | 9 the high impedance node is sensitive to interference and noise.
If the interface is off-chip it is really a problem since your circuit will
easily pick up noise and so on from the ambient;
If the interface is on-chip it might be better
If the output is low imp, the input of the following stage is high imp, then
it is a low impedance node and therefore free of the problem I mentioned
above.
There might be other reasons though... |
|
d******a
发帖数: 57 | 10 测量电容
Lab里只有HP4194A impedance analyzer 看paper好像很多人都用HP4284A LCR meter
用4194测impedance然后算capacitance 和直接用LCRmeter测量有本质区别吗？
thanks |
|
x*******2
发帖数: 5333 | 11 【 以下文字转载自 Physics 讨论区 】
发信人: xmdxx1182 (卡西莫多), 信区: Physics
标 题: 有人懂impedance吗
发信站: BBS 未名空间站 (Fri Apr 8 13:58:18 2011, 美东)
一般镀膜impedance都是显示电容和电阻串联，结果我显示是电感和电阻串联。有人能
指点一下这是为啥吗？ |
|
a**r
发帖数: 224 | 12 【 以下文字转载自 Chemistry 讨论区 】
发信人: amor (果冻布丁), 信区: Chemistry
标 题: eBook help: Impedance spectroscopy. Princeton, Columbia,
发信站: BBS 未名空间站 (Thu Apr 24 16:08:35 2008)
Title: Impedance spectroscopy [electronic resource] : theory, experiment,
and applications.
Edition: 2nd ed. / edited by Evgenij Barsoukov, J. Ross Macdonald.
Published/Created: Hoboken, N.J. : Wiley-Interscience, c2005.
到各大学校的图书馆逛了一下
Princeton, Columbia, UCSC, UCM 有电子版
请这些学校的xdjm帮个忙，
包子答谢
Please email to: a*********[email protected] |
|
b****y
发帖数: 103 | 13 well I never heard about the impedance of an optical system
I ponly heard about the impedance of a eletrical circuit
so what's your defination? |
|
b****y
发帖数: 103 | 14 here is what I think.
I guess you want to characterize the impedance of a waveguide.
from the reference in wikki, it seems to me that you only need to figure out
the cutoff frequency.
so maybe you can first estimate the cut off frequency, then get a tunable
laser near that range, and find out the cut off frequency by fine tuning the
laser.
after the cut off frequency is found, you can get the impedance |
|
T*U
发帖数: 22634 | 15 impending traffic may not be as lethal as speeding, but sure it cause more
accident.
don't get involved into any kind of impeding traffic. |
|
M*******c
发帖数: 4371 | 16 Exactly
the LCR meter could only configure L-R or C-R in series or parallel.
So you will have error due to the parasitics. Because the LCR could not
identify the impedance from L or C. |
|
s***d
发帖数: 15421 | 17 个人认为要impedance matching，这样LNA的gain能最大话，并且能够减小mixer 的NF，但是看了很多paper，貌似都没有考虑matchng，LNA输出都是按照50ohms matching的 |
|
s***d
发帖数: 15421 | 18 我的理解是那如果两者之间直接ac couple，因为mixer 的 input impedemce 并不是
LNA output impedance 的 conjugate，所以LNA的 gain 肯定会有所降低吧，那么我们
有必要调整mixer 的size ，是gain 不至于太小吧，而且nf不太大，整个系统的 nf最
小？ |
|
H***F
发帖数: 2501 | 19 mixer 也分passive和active，passive的话是current in，不用conjugate。active的
是voltage in, 也不用conjugate
我的理解是那如果两者之间直接ac couple，因为mixer 的 input impedemce 并不是
LNA output impedance 的 conjugate，所以LNA的 gain 肯定会有所降低吧，那么我们
有必要调整mixer 的size ，是gain 不至于太小吧，而且nf不太大，整个系统的 nf最
小？ |
|
x***y
发帖数: 830 | 20
max
Interstage impedance matching is dorable, at the cost of area. |
|
c*****e
发帖数: 44 | 21 【 以下文字转载自 Optics 俱乐部 】
发信人: chuckle (Stressed INFJ), 信区: Optics
标 题: For a optical system, how to measure the impedance?
发信站: BBS 未名空间站 (Thu Aug 20 10:26:45 2009, 美东)
Sincerely ask: Are there any standard method, or what methods have been
tried?
Thanks very much. |
|
x*******2
发帖数: 5333 | 22 一般镀膜impedance都是显示电容和电阻串联，结果我显示是电感和电阻串联。有人能
指点一下这是为啥吗？ |
|
D**********s
发帖数: 3139 | 23 音量控制对音质的影响，以前有一篇note写得不错，我找了半天才找到，其实还有用变
压器的方法，不过dac这块最保真的方法就是保持位深和标准输出电平，音量控制交给
前级和功放去管就好了，终究绕不过模拟放大这一关的。
Volume Control Technologies
Newsletter Edition:
July 2009 Issue
With the introduction of Benchmark’s HDR-VC™ (High Dynamic Range
Volume Control), many audio enthusiasts are taking another look at volume
control methods. What are the differences between the different volume
control topologies? Is one sonically superior, and why?
The important qualities to consider with respect to volum... 阅读全帖 |
|
f**d
发帖数: 768 | 24 这是一本计算神经科学的优秀著作，全文拷贝这里（图和公式缺），有兴趣的同学可以
阅读
如需要，我可以分享PDF文件（－－仅供个人学习，无商业用途）
From Computer to Brain
William W. Lytton
From Computer to Brain
Foundations of Computational Neuroscience
Springer
William W. Lytton, M.D.
Associate Professor, State University of New York, Downstato, Brooklyn, NY
Visiting Associate Professor, University of Wisconsin, Madison
Visiting Associate Professor, Polytechnic University, Brooklyn, NY
Staff Neurologist., Kings County Hospital, Brooklyn, NY
In From Computer to Brain: ... 阅读全帖 |
|
b********n
发帖数: 38600 | 25 http://www.strategypage.com/htmw/htlead/articles/20120807.aspx
Can't We All Just Obey China?
China recently declared that most of the 3.5 million square kilometers South
China Sea had become Sansha, the latest Chinese city. The area China claims
is within the city limits comprises over two million square kilometers of
largely open ocean and a few hundred tiny islands and reefs, many of which
are only above water during low tide. Sansha is administered from one of the
Paracel islands (Woody Islan... 阅读全帖 |
|
s**a
发帖数: 1995 | 26 本版大拿，不少小白，像我一样入手了这对音箱，但对给这对音箱匹配一个合适的功放
是给个难题。我看了看手头的资料，还是不太明白，哪位能以这对音箱为例讲解一下匹
配音箱和功放的原则，比如，六欧姆不是典型的阻抗值，怎么计算合适的功率，除了功
率以外还有什么指标要匹配如何匹配等等，实在是功德无量的好事。本人愿意全部包子
赠送。
先锋BS-41指标如下
Enclosure ... Bass-reflex Bookshelf Type
Configuration ... 2-way
Frequency Range ... 55 Hz-20 kHz
Nominal Impedance ... 6 Ohms
Sensitivity (2.83 V) ... 85 dB
Maximum Input Power ... 130 W
Crossover Frequency ... 2.5 kHz
amazon有个ONKYO TX-8050 2.0的receiver，我比较喜欢它的数字输入比较多，光纤/
usb/coax都有，而且列出来的6 Ω loads 100W 功率貌似也够了。他的电气指标如下。
哪位如... 阅读全帖 |
|
k******9
发帖数: 878 | 27 如果准备买JBL ES80，那Onkyo TX-NR626可以搭配吗，我把参数都列在下面，麻烦高手
看看，谢谢了
JBL ES80. Specifications General Specifications Finish Black Series ES Wall-
Mount Capable No Type Floorstanding Audio Specifications Crossover
Frequencies 700Hz, 3.6kHz a?" 24dB/octave; 12kHz a?" 18dB/octave Maximum
Recommended Amplifier Power 200W Power Handling (Recommended) 100W
Sensitivity (2.83V@1m) 91dB Power Handling (Peak) 400W Nominal Impedance 8
ohms Frequency Response 45Hz a?" 40kHz Speaker Specifications High-Frequncy
Transduc... 阅读全帖 |
|
X***0
发帖数: 91 | 28 本屌比较郁闷，被Tesla,Western Digital, Maxim, Arecont Vision几个公司在第一轮
电面给灭了。今天刚刚面完LSI，心情无比沉重。为攒人品，愿意分享失败的经历。
首先介绍本人背景，EE的ms在读，5月份毕业。EE学的比较杂，embedded+analog+
control+power都有涉猎。目前主要着重在embedded领域就业。
今天下午刚刚面的LSI，所以印象比较深刻，就从这里说起 。职位是Application
Engineer，一个老印口音极重。问的问题有5个方面。
1. Digital Logic.
How to implement inverse gate from NAND?
How to implement inverse gate from NOR?
How many sel lines for a 100 input multiplexer?
Describe D flip flop.
2. Analog.
What is impedance?
What is impedance mismatch? How to avoid?... 阅读全帖 |
|
k******9
发帖数: 878 | 29 这种卡拉OK要求的音响，有什么参数要求，这方面一窍不通，听大家说音响容易烧坏，
那是要哪个参数高或者低？有具体的选购参数标准吗？
我在版上翻了翻，有推荐JBL ES80的，还有BOSE301的，前几天看到NEWEGG上有POLK打
折的，等等等，大家可以给个建议吗？
另外如果选好了音响，如何看功放的参数和音响是否匹配，不会烧坏也不会推不上去，
那要看哪几个项目的数值，实在是什么都不懂，望高手帮忙！感激不尽
如果准备买JBL ES80，那Onkyo TX-NR626可以搭配吗，我把参数都列在下面，麻烦高手
看看，谢谢了
JBL ES80. Specifications General Specifications Finish Black Series ES Wall-
Mount Capable No Type Floorstanding Audio Specifications Crossover
Frequencies 700Hz, 3.6kHz a?" 24dB/octave; 12kHz a?" 18dB/octave Maximum
Recommended Amplifier... 阅读全帖 |
|
发帖数: 1 | 30 impedence, impedence, impedence, 重要的事情说三遍。如果不想弄坏amplifier 和
speaker的话，一定要看impedence. |
|
P****n
发帖数: 202 | 31 Open the green caps, you will see the solenoids that controls water flow.
Open it manually to see if you can have water flow at corresponding heads.
If not, most likely a water pipe problem. Go find a plummer.
For electrical problem (most likely cause), find your control panel for your
irrigation system (mostly on garage wall). Read your manual or trouble
shooting guide (google it) for your irrigation system. You will find
instructions on how to test the system with a cheap multimeter. Control
p... 阅读全帖 |
|
s*****i
发帖数: 5548 | 32 ☆─────────────────────────────────────☆
duoduo3 (duoduo) 于 (Wed Aug 3 11:55:30 2011, 美东) 提到:
换个sprinkler 喷头啥的都会，但是后院的喷水系统自从搬家过来从来没work过，今年
的德州天气要死人，后院的植物都奄奄一息，打算自救修一下，原来铺设的都还在，后
院三个zone，是不是先找Valve，但好像Valve都埋在地里，不知道怎么找valve。 有经
验的吭一声。谢谢。
☆─────────────────────────────────────☆
nkfly (南开阿飞) 于 (Wed Aug 3 11:56:30 2011, 美东) 提到:
一声都不敢吭。。。
☆─────────────────────────────────────☆
duoduo3 (duoduo) 于 (Wed Aug 3 11:58:25 2011, 美东) 提到:
你还是吭了
☆─────────────────────────────────────☆
Hak... 阅读全帖 |
|
s*******s
发帖数: 5087 | 33 【 以下文字转载自 Shaanxi 讨论区 】
发信人: xinyuemba (小树), 信区: Shaanxi
标 题: 【人在囧途】之英语发音（18+）
发信站: BBS 未名空间站 (Wed Dec 8 13:19:50 2010, 美东)
这是我自己闹过的几个英语发音笑话，不幸都有点儿带色儿，我牺牲一把，大家开心一下。
1.Impedance and Impotence
这个是我在实验室闹的笑话。
某日俺做实验，一个东西不会做，就抓一美国帅哥问：
“Do you know how I measure the impedance level?”
Impedance是阻抗的意思，发音应该是：/im'pi: dens/
重音在第二个音节上，e发长音i:
结果我说了个 /'impedens/， 这里的e要反过来哈，俺打不出来那个符号。
帅哥愣住了，说：
“Measure impotence?”
Impotence是阳萎，发音是：/'impetens/
于是，我就又强调了一遍：
"Oh, yeh, suppose you have an impedance, how do you m... 阅读全帖 |
|
x*******a
发帖数: 11067 | 34 这是我自己闹过的几个英语发音笑话，不幸都有点儿带色儿，我牺牲一把，大家开心一下。
1.Impedance and Impotence
这个是我在实验室闹的笑话。
某日俺做实验，一个东西不会做，就抓一美国帅哥问：
“Do you know how I measure the impedance level?”
Impedance是阻抗的意思，发音应该是：/im'pi: dens/
重音在第二个音节上，e发长音i:
结果我说了个 /'impedens/， 这里的e要反过来哈，俺打不出来那个符号。
帅哥愣住了，说：
“Measure impotence?”
Impotence是阳萎，发音是：/'impetens/
于是，我就又强调了一遍：
"Oh, yeh, suppose you have an impedance, how do you measure it?"
2. Caulk and Cock
某日在office，因为家里水管漏了，我在网上做了研究，找到这里可以用一种叫做
Caulk的东西堵漏。俺不知道这东西在哪里买，就对着Officemates们大喊：
"Hi guys, do y... 阅读全帖 |
|
c******h
发帖数: 454 | 35 my 2 cents
1. CG has low input impedance 1/gm, so it can be used as input stage in high
speed design for the impedance match 75 ohm. Unlike inductance RF design,
it offers wideband.
2. For output stage, follower is often used because we want low impedance to
drive high impedance for a voltage source. C-G is opposite.
3. For noise consideration, C-G and C-S have same noise performance.
C-S is Vsignal/Vnoise (both refered to gate)
C-G i signal = V signal / Rin (Rin = 1/gm)
i noise = v noise gm, so |
|
h******v
发帖数: 30 | 36 The Differential Input Impedance of OPA656 (Wideband, Unity-Gain Stable, FET
-Input Operational Amplifier) is given as
10^12 Ohm || 0.7 pF. Does 10^12 Ohm mean the DC Input Impedance? How to calc
ulate the differential input impedance for
AC signal, say f=10MHz? Is the following correct?
Zin=1/(2*3.14*f*C)=1/(2*3.14*10^7*0.7*10^(-12))=20kOhm
I want to monitor a 0.1V/10MHz signal which has source impedance as high as
100MOhm by oscilloscope. Is there any chance?
Reference article:
"High- |
|
l****o
发帖数: 184 | 37 这个计算transfer function的方法确实不错，简化了不少，只是如果把output
resistance全部省略，会不会对最后的gain计算会有影响？
Additional amplifier确实只是boost the output impedance,,整个amplifer得gm 还
是约等于gm1,但是你如果计算一下the impedance @V1， 你会发现V1 is voltage
sampled, and the impedance is
1/(gm2*(AGE+1)),
当然在那么高的frequency，AGE早就消失了。
换个角度来说，GE amplifier的作用就是keep the drain of bottom transistor more
constant.当然相对来说，the impedance at V1 is smaller.
不知道这样的说法对不对
opamp
/ |
|
s*****n
发帖数: 2 | 38 1) Without feedback, assume the impedance looking up at the source of M3 is
RD, then the impedance looking at the source of M3 is
Rin = (RD+Ro3)/(1+gm3*Ro3) = (RD+Ro3)/(gm3*Ro3)
2) M1 senses the Iout (Iout*RD) and feedback the current to input node gm1*
RD*Iout, loop gain T = gm1*RD
3) shunt feedback at the input --> Rin_eff = (RD+Ro3)/(gm3*Ro3*gm1*RD) (
ignore the 1+T factor)
4) Now look at the RD, 坑爹, depends on the load impedance:from the fig,
assume no loading,
RD = Rdsp || (gmn*Rdsn^2+Rds... 阅读全帖 |
|
w*******y
发帖数: 60932 | 39 Newegg has the Onkyo HT-RC360 receiver for $279 with promo code EMCJJKB83
Link:
http://www.newegg.com/Product/Product.aspx?Item=N82E16882120178
Processing
Power Output
Front L/R:
100 W + 100 W (8 ohms, 20 Hz-20 kHz, 0.08%, 2 channels driven, FTC)
125 W + 125 W (6 ohms, 1 kHz, 0.1%, 2 channels driven, FTC)
Center:
100 W (8 ohms, 20 Hz-20 kHz, 0.08%, 2 channels driven, FTC)
125 W (6 ohms, 1 kHz, 0.1%, 2 channels driven, FTC)
Surround L/R:
100 W + 100 W (8 ohms, 20 Hz-20 kHz, 0.08%, 2 channels driv... 阅读全帖 |
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k*****n
发帖数: 9823 | 40 ☆─────────────────────────────────────☆
hifiman (hardcorehifi) 于 (Tue Mar 3 13:48:39 2009) 提到:
My Adcom 500 GTP phonejack has bad connection, and the left channel is cut
off. I am think about hooking up my headphone directly to its amp out.
Have any of you tried this before? My Senn 600 is 600 ohm impedance and I
need to check the Adcom's output impedance to see if them are close. I
think the only downside is degraded sound quality because of the mismatch of
impedance, but generally sp |
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s*****o
发帖数: 1540 | 41 我对音响一窍不通，希望大侠推荐300元之下的功放:
http://www.martinlogan.com/pdf/manuals/manual_mlt2.pdf
MLT-2 SPEAKER (front and rear)
System Frequency Response
110–20,000 Hz ± 2db
Sensitivity
88 [email protected] volts/meter
Impedance
8 Ohms compatible
Crossover Frequency
2000Hz
Tweeter Type
1” (2.54 cm) soft dome
Woofer Type
4.5” (11.5 cm) high rigidity poly cone
with extended throw drive assembly
Enclosure Type
Non-resonance asymmetrical
chamber format, sealed
Suitable Amplifier Range
15–100 watts
Power Handling
50 watts
Wei... 阅读全帖 |
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s****h
发帖数: 3979 | 42 没人帮着回答一下呀？
我自己瞎说一下，看看对不对
以Klipsch Reference RF-52 为例子
它的数据是：
1）100W RMS / 400W Peak
2）8 ohms
这个speaker是8ohms nominal，就是平均8 ohm的意思。
RMS是平均值的意思（猜的），对应的就是8ohm，peak值是平均值的4倍，也就是说最小
Impedance是8ohm的一半，4ohm
(这么看起来，8ohm和100w这两个平均值，最多只有一个是在Frequency Response 内的
线性平均值。)
那么以Energy CF30为例子
1) 20-200 W /channel
2) 4 Ohms min./8 Ohms nominal
那么最小Impedance 4ohm对应200w
20w对应最大Impedance，大约是12 ohm
平均是50W/channel
receiver的spec：
Channels：5
RMS Output Power (1kHz)： 100W x 5
Total Power (20Hz - 20kHz)： 500W (1kHz ）
推动... 阅读全帖 |
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s***a
发帖数: 4921 | 44 http://www.metrohm-autolab.com/Products/Echem/ModulesFolder/FRA
It has widespread application in the field of characterization of materials.
It is routinely used in the characterization of coatings, batteries, fuel c
ells, and corrosion phenomena. It has also been used extensively as a tool f
or investigating mechanisms in electrodeposition, electrodissolution, passiv
ity and corrosion studies, diffusion of ions across membranes, study of semi
-conductor interfaces and biosensors.
The Autolab us... 阅读全帖 |
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f*****0
发帖数: 489 | 45
impedance
dumb ass. the signal is a current source (with infinite output
impedance), and the output voltage is always the input current times Rf
(500K), and has nothing to do with source impedance.
Stupid jerk! |
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ET
发帖数: 10701 | 46 较劲不较劲是load 不load each other.
如果电源2的ouput impedance + 串联的resistor load电源1，(which i think not po
ssible,but i might be wrong), 会改变电源1的行为，那么就是问题。
1个电源能给asic供电，它的output impedance应该比asic大不少。
所以就像电源1 load 2个high impedance的电阻。
虽然我不知道楼主的问题的意义何在，比如是想观察rms value还是怎么的，但我不认为
他的办法达不到他想要的结果。 |
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c*****e
发帖数: 43 | 47 遇到一个仿真的问题，大致情况是这样的：在layout画了一个two-port network，里面
用ADS Momentum得到的s paramater 然后转化成z parameter.这个转化用matlab 的
function或ADS自带的stoz()都算过，结果是一致的。 然后我把这个layout转化成一个
component, 用于我的一个简单的电路图中。这个电路图里面，我测量两个port的电压
V1, V2，和电流I1, I2，然后为了验证，我带入Z-parameter运算，照理来说应该要V=Z
*I, 可是等式左右不相等，并不是符号不对，而是数值相差太多。
不知道问题出在哪里？
另外我询问了agilent support,他们给了我一段摘抄于他们knowledge center的话，如
下。可我还是不懂，这里说的意思是有两组不同的z-parameter吗？我只听说过open
circuit下算出来的z-parameters.不知道我哪里理解错了.麻烦看看，感谢大家了。
Why (Z11)s are different?
Issue
I have a two port n... 阅读全帖 |
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y******9
发帖数: 606 | 48 ADS support提出了reference impedance的问题。说s parameter的时候，都有
reference impedance，一般default是50ohm，如果reference impedance不同，对应的
s parameter就不同。 |
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y***o
发帖数: 145 | 49
abuse office penal codo, only the DEPT of Justice or attorney general 可以起
诉： for judge Downing did not excute the law.
PENAL CODE
TITLE 8. OFFENSES AGAINST PUBLIC ADMINISTRATION
CHAPTER 39. ABUSE OF OFFICE
Sec. 39.01. DEFINITIONS. In this chapter:
(1) "Law relating to a public servant's office or employment" means a law
that specifically applies to a person acting in the capacity of a public
servant and that directly or indirectly:
(A) imposes a duty on the public servant;... 阅读全帖 |
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