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Help creating PCB

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Soloratov

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Hello everyone, I am hoping there might be a few people here that can help me out. I have a simple timer circuit I am trying to create, and then turn into a working PCB prototype. Problem I have, is I am very, very lacking in knowledge when it comes to electronic design.

If anyone could take the following info, and proposed circuit diagram and create a PCB layout...I would forever be in your debt.

Requirements:

12vDC power supply
15 second timer
Operation - Momentary push button switch causes a motor to turn on for 15 seconds, then auto shutoff.

Motor is connected to PCB via a lead with removable connector
Switch is connected the same way
12vDC power is supplied into PCB via a cable which is soldered to the board.
Motor draws ~100 milliamps during operation


Attached is the proposed schematic I had found online, but I know so little I am quite confused what to do with it.
 
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Would you post a pic of your circuit? I tried the link, and maybe i'm doing it wrong, but it does not show me the circuit
 
This is the circuit in the documnet for anyone who had difficulty opening it:

View attachment 67670

That is simply a one-shot. The output is low until the switch is closed. Then it goes high for the time determined by R1 and C1. It returns low.

You would attach your motor and its power supply to the relay (N.O. contacts) so that when output is high and the relay is activated, the motor runs. You will need to calculate R1 and C1 to give 15 seconds. The formula is in the 555 datasheet.

John
 
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Here is the listing of parts the circuit calls for on the diagram sheet:

Parts:
• C1 10uf 16V Electrolytic Capacitor
• C2 0.01uf Ceramic Disc Capacitor
• R1 1 Meg Pot
• R2 10 K 1/4 Watt Resistor
• D1,D2 1N914 Diodes
• U1 555 Timer IC
• RELAY 9V Relay
• S1 Normally Open Push Button Switch
• MISC Board, Wire, Socket For U1
Notes:
• R1 adjusts the on time.
• You can use a different capacitor for C1 to change the maximum on time.
• S1 is used to activate the timing cycle. S1 can be replaced by a NPN transistor so that the circuit may be triggered by a computer, other circuit, etc.
 
If you download (free) Eagle Lite you can use it to input the schematic and it can, with a little work on your part in arranging the positions of components, create a PCB layout.
 
I think my reason for confusion, is looking at the diagram, I see a lot of the connections are shared, and that doesn't make sense to me. Is pin 3 really the only thing not directly connected to all the other components? Also, why is the pin arrangement in the diagram so off from the real pin diagram in the software?
 
I see a lot of the connections are shared, and that doesn't make sense to me.
It is very common for connections to be shared. For example the circuit ground line (conventionally shown along the bottom of the schematic) usually has many components connected to it.
Is pin 3 really the only thing not directly connected to all the other components?
No. Pin 5 of the IC connects only to C2.
Also, why is the pin arrangement in the diagram so off from the real pin diagram in the software?
A schematic shows the logical connections of pins of components. For convenience, to avoid a tangle of lines, that may be different from the relative physical positions of the pins.
 
Ok, I guess that all makes sense. So I did my best with it, but would like someone to check my work, provide insight perhaps. To me it is an absolute mess, which I can understand now why these lines are called nets.
 
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