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You can now see all of the connections to the ground plane. You can do the same thing for the power plane. Press ‘ F5 ’ or the Refresh All button to make the whole design visible again.

We still have one voltage net to route, and that is the input voltage from an external power supply. This net only touches a few components, so we could just put a trace to connect all the components. However, we can also draw a solid piece of copper and associate it with that net. This is especially useful for high-current traces or small voltage planes. We do this using the Obstacle Tool just like when drawing obstacles for footprints. Turn the Obstacle Tool on and then right-click anywhere in your design. Select New… and then right-click again and select Properties… to bring up the Edit Obstacle dialog. Name this obstacle VCC_IN, leave the Width at 10 mils. Set the Clearance to 15 mils Change the Obstacle Type to Copper pour. Finally, set the Net Attachment to the name of the net, which should be V_IN . Click OK and you are ready to draw your copper pour. Draw a rectangle around the power connector and other components that are attached to this net. When you are done, click Refresh All to redraw the ratsnests.

You have now routed all the power and ground connections. That was easy, right? Let’s look a little bit at some of the tools that OrCAD gives you to check on the progress of your design. Click the View Spreadsheets icon and choose Statistics . The statistics spreadsheet gives you information on time in layout, percent of components placed, percent of traces routed, and some other information.

100% of your components should be placed, and you can also see that a majority of your traces have been routed (power and ground make up the majority of connections in most designs). You are well on your way to completing your design.

Routing other nets

You are now prepared to route the other connections on your board. Open the nets spreadsheet and highlight all the nets in the design. Right-click and select Enable<->Disable to make the ratsnets visible for the remaining nets. Refresh the display to clean things up a bit.

Before beginning routing in earnest, it is helpful to change a few settings. Open the System Settings and make the following changes: Visible Grid = 10, Routing Grid = 5, and Via Grid = 0. Next, select Options-->User Preferences and check Allow DRC Errors under Global Preferences . You may have to check the box labeled Activate Online DRC . The box with the dashed line will reappear. While DRC is on, you will only be able to place routes inside this box, but Layout will inform you if any spacing errors occur while you are routing. This will help you limit the number of errors that you will have to clean up later. You can resize the DRC box by pressing ‘ B ’ and drawing a new rectangle.

Let’s route a connection. Turn on the Edit Segment Mode or Add/Edit Route Mode .

Routing Mode Icons
The two have some subtle differences. Experiment with both to see which one you are most comfortable with. Let’s start by routing the connection for the pushbutton switch. Zoom in a bit and click on the ratsnest near pin 4 of the switch. Left-click to place a segment of a route. When you get near to pin 3, you can press ‘ F ’ to have Layout finish the trace for you. Pins 3 and 4 should now be connected. Now connect the resistor and capacitor that are nearby.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket 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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