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Next, choose Auto-->Rename Components . You silkscreen should look a lot different now.

Before Renaming
After Renaming

Since you have changed the reference designators in your design, you need to generate a swap file and perform back annotation. You should do this IMMEDIATELY . If you don’t, it can cause some serious problems for you later in the design. When you read the swap file into Capture, you may get errors on renaming the mounting holes. It is safe to ignore these.

Checking for errors

The next step in the design process is to check for any spacing errors. OrCAD uses the spacing variable that you set earlier to determine if there are errors in your design. We used 10 mil spacing from all features as a minimum for this design. To perform a Design Rule Check (DRC) choose Auto-->Design Rule Check… from the menu.

Make sure all the Check Rule Settings are checked and click OK . Your design will rarely contain no errors, and you will need to look at the errors spreadsheet to see what the errors are. Some can be safely ignored.

In this example there are four Pad Spacing Errors, one generated by each of the mounting holes. In this case OrCAD is complaining because the place outline for the part is on the edge of the board. This error is OK to ignore. If there are errors that need to be fixed, you can delete the marker from the spreadsheet. Let’s generate a route spacing error so you can see what it looks like. These are the most important. Move a trace anywhere in your design so that it conflicts with another trace or pad.

Now rerun the DRC. The new errors should appear in the spreadsheet.

You can remove the errors by moving the trace back to its original position. Once the error has been corrected, you can delete the marker from the errors spreadsheet. Do not try to use the Auto-->Remove Violations tool. It is tempting, but it will actually rip up offending traces and move parts. You will end up having to do a lot of cleanup and rerouting after using this tool.

Cleaning up&The design

Now it is time to clean up your design. You should think of your board as a work of art. Other people may look at it, so you want it to look nice. Furthermore, a clean design will ensure fabrication success. When cleaning the design, the following should be kept in mind.

A. Route Spacing – You have set a minimum of 10 mils for feature spacing in your design. However, do not pack traces closely together unless you have to. First, you can push the manufacturing limits to far and some of your boards may come back bad. Second, routing traces closely together is generally a bad idea because this can result in undesired mutual inductance between traces.

B. Right Angles in Traces – Don’t use right angles in routing your traces. Miter the corners.

BAD
GOOD

C. Pad Exits – Trace exits from pads should be clean and not come out of the pad at unusual angles.

BAD
GOOD

D. Remove Extra Vias – Vias add cost to a board, so it is a good practice to remove any unnecessary vias from your design.

E. Drills – Drills require some special attention. First, you need to fix the error you got earlier about the drills. This error occurs sometimes after you perform an ECO. To see the problem, make the Drill Drawing (DRD) layer visible. Press Backspace to clear the display and then Shift-5 to display just the DRD layer.

Questions & Answers

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
I know this work
salma
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
Abhi
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
hmm
Abhi
is it a question of log
Abhi
🤔.
Abhi
I rally confuse this number And equations too I need exactly help
salma
But this is not salma it's Faiza live in lousvile Ky I garbage this so I am going collage with JCTC that the of the collage thank you my friends
salma
Commplementary angles
Idrissa Reply
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
hii
Uday
hi
salma
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
Kim
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Al
y=10×
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, High-speed and embedded systems design (under construction). OpenStax CNX. Feb 18, 2004 Download for free at http://cnx.org/content/col10212/1.12
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