Eagle & proteus help !

[stonex]

Hi guys ,
1) How to ensure that all the lines are connected in eagle , sometimes when opening the PCB window , some components are not connected even it looks connected in the schematic , so i delete the lines and redraw them , but its not practical in big circuits .
2) does eagle have double ganged potentiometer , and how to connect potentiometer in eagle sometimes it goes wrong .
3 ) i needed a transformer ( center tapped ) but in the PCB preview says that its very small less than 1cm but the transformer i have is at least 4 cm * cm4 , where in eagle to find suitable one .

4) in Proteus , how to wire the transformer to 220 vac , so i can simulate the circuit and measure the out voltage , also how to wire the potentiometer .
5) how to assign value for the transformer (12vac, 1amp , center tapped ) so that Proteus considered it when simulating .
any help will be great .
regards ,

 

[Rexlan]

In Eagle your nets are not connected on the schematic if you see un-routed rat lines on the PCB. If you zoom in on the schematic and then select the "eye" to highlight the net you will see there is no connection. Delete the line and draw it again. Sorry if it is a PITA but that is the way it works and should work ... LOL. If it isn't practical you will have to send it out and have someone do it for you.

You need to set a realistic grid to work with in the beginning and NEVER assume the nets are connected. If you run the scripts it will tell you before hand where the problems are.

There are zillions of PCB components and it is unreasonable to expect to find every one of them in the library to you needs. You will need to draw and configure your own custom parts for those you need. Again if this is something you don't think is practical you will have to pay someone to do it for you.

Eagle is very robust and it is probably one of the best out there. Eagle NEVER makes a mistake ... it is the user who has made the mistake.

If you EVER close the schematic or the board file and make a change you are screwed forever as the annotation will no longer work. Always have both files open at all times.

 

[mneary]

When making a schematic with Eagle, adjust snap length and catch factor (see help). It's in the Options menu, under 'set'. Tab is 'misc'. This will make Eagle more aggressive in finding the nearest pin if you don't tend to be precise with your clicks.

 

[Boncuk]

also switching to a grid size from e.g. 0.1" (2.54mm) to 2.5mm won't do any good. You'll not be able to see the unconnected net.

Always use a grid size based on imperial measurement.

Boncuk

 

[Wond3rboy]

About Eagle, i ensure connections by putting junctions and naming the connections, if the name is on the whole wire i know its connected.But it does make it a bit "dirty". I choose the smallest grid( better boards as far as i am concerned )

About Proteus, use the generator mode( keeping it simple) use a sine generator. when using a pot use the active one( the one in which you can change the resistance during simulations)/ Give the schematic and i will be happy to connect it for you if you are having any problems.

 

[stonex]

Thanks a lot for these tips guys .
Rexlan , great tips , about the missing part , you are right i will have to draw it by myself .
mneary . this really helped , thanks
Boncuk. i always keep the grid size 1mm
Wond3rboy , will give it a try . about Proteus , i will try doing it ; if it doesn't work , will let you know . thanks .

 

[stonex]

About Eagle, i ensure connections by putting junctions and naming the connections, if the name is on the whole wire i know its connected.But it does make it a bit "dirty". I choose the smallest grid( better boards as far as i am concerned )

About Proteus, use the generator mode( keeping it simple) use a sine generator. when using a pot use the active one( the one in which you can change the resistance during simulations)/ Give the schematic and i will be happy to connect it for you if you are having any problems.

Wonder3boy , it didn't work , the Proteus circuit , and i attached it hope you can fix it .
thanks

 

[Wond3rboy]

Hi Stonex the circuit that you posted has a lot of problems with it, set the component values again, the input to the bottom part is grounded so no input voltage will be present. I couldnt edit your circuit since i dont have ARES installed and it wouldnt let be delete any component otherwise. I am uploading a sample circuit of a 5V supply using the 7805 (i havent calculated the component values so please overlook those). What you can do is either follow my circuit or add yours to it. If you have any questions then come again k.

PS: I saw that you havent changed the voltage on the transformer secondary. Do that by changing the Coupling Factor in the component properties.

 

[stonex]

Hi Stonex the circuit that you posted has a lot of problems with it, set the component values again, the input to the bottom part is grounded so no input voltage will be present. I couldnt edit your circuit since i dont have ARES installed and it wouldnt let be delete any component otherwise. I am uploading a sample circuit of a 5V supply using the 7805 (i havent calculated the component values so please overlook those). What you can do is either follow my circuit or add yours to it. If you have any questions then come again k.

PS: I saw that you havent changed the voltage on the transformer secondary. Do that by changing the Coupling Factor in the component properties.

Wond3rboy , i don't know how i missed that , i fixed these errors , and followed your circuit which helped me a lot .
so i changed the coupling factor until i got the voltage i wanted (12vac )
i decided to start making it from scratch , so it would be much easier to correct , and testing the output at each step . so when i added the 4 diodes ( the bridge ) i think that the output rectified ac voltage should be
(( the secondary voltage (12vac) * 1.414 ( Square root of two ) - 0.7 * 4 ( voltage drop across the 4 diodes ) ))
so its 16.9 - 2.8 = 14.1 vac , ( correct me if I'm wrong )
but it varies a little some times , ( CPU clock , ram , don't know )
when i add a capacitor "the reservoir" , the output after the capacitor is Zero , and the output after the secondary changed from about 12vac to 9 vac or any other value depending on the value of the capacitor i added .
I'm trying to figure out whats the problem here , so what do you think ?.
===
BTW , you mean ISIS , by Ares , right .

Thanks wond3rboy for you time and help .

 

[Wond3rboy]

Hi Stonex, ARES is right , since i dont have it installed(the pcb one) ISIS doesnt allow me to delete components. Secondly connecting a reservoir capacitor doesnt make its output zero (unless you are connecting one in series ending up with an RC circuit with the wires resistance). About the wobbling of the output.. i know, its because the parameters of the transformers are not set optimal. Even in the simple transformer that i have shown, it is not a 'clean' sine wave. Also the voltage doesnot droop after placing a capacitor on the transformer secondary. See this.

 

[belal545]

Thanks @ Wond3rboy for this 220vto5v.zip

Belal