# Basic circuit

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Hello

I am not sure is this the right group to post this kind of question, I
hope I am not too much out off topic.

I am quite new to electronics, although I am programming software
already for many years. I understand very basic circuit's schematics,
but for this
http://www.captain.at/electronics/atmel-programmer/atmega16-programmer.png
particular one (I saw it on other places also), I am not sure how the
lower right part comes into the circuit. I mean, it is totally
disconnected from the main part of the circuit. What's the purpose of
it and how connects to the other part, can someone explain it to me?

Thanks
Goran

Re: Basic circuit

VCC_OUT should be VCC or am I wrong ?

Re: Basic circuit
Probably, I see now. You mean the arrow in the left up corner near R4,
right? It continues with VCC_OUT. I hope it is like that.

Thanks

Re: Basic circuit
Or you mean VCC at pin 10? Now I am confused again. Then what is VCC at
R4?

Re: Basic circuit

It's the same signal, the arrow indicates a connection.

Re: Basic circuit

IC2, C3, C4, and C5, are a very poorly drawn voltage regulator.

It does appear that way, unless you recognize that the node VCC_OUT
should be labeled VCC and connects to the other nodes labeled VCC.

It accepts the 7 to 30 volt input at the bottom and provides a source of
regulated 5 volts for the rest of the circuit.

Again, the node labeled VCC_OUT connects to the nodes labeled VCC and
all of the nodes labeled GND are connected to each other, too.

'Salright.

--
========================================================================
Michael Kesti            |  "And like, one and one don't make
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Re: Basic circuit

The "mystery part" is a voltage regulator - it will accept 7 - 30
volts, and reduce it to 5 volts for the processor.  The point labelled
"VVC_OUT" should be labelled "VCC".

All the points labelled "GND" are connected together, and all the
points labelled "VCC" (including the mislabelled "VCC_OUT") are
connected together.

When drawing schematics, it is common practice to omit power and
ground lines, and to indicate the connections with "VCC" and "GND"
symbols, or signal names (often called "net labels") to reduce clutter
on the drawing.

--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
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Re: Basic circuit
Thanks to all, I appriciate your help. It was really unclear to me, but
now I think I got it.

Regards,
Goran

Re: Basic circuit
You probably want to check LS78L05Z datasheet.

I remember that Pin 1 on 7805 is input pin, pin 3 is output pin. But
the schematic suggest pin 1 is the output pin ( that you should label
as VCC).

Check that again, cos making a PCB is expensive and takes a lot of
time, specially in my country :p

Re: Basic circuit

I will do that. Just, I am still searching for the parts. My country is
also very bad in this field (as in many others).
I will probably need to order them over the net. I found them on
www.futurlec.com, disent prices I would say and they accept cheques,
which is a must in my case.

I remeber you from my previous thread in this group, if you remember
AVREasy. I couldn't get it running, so I decided to make something on
my own. Just I can't forgive my self, I paid the board 120 euros, while
they on the above site are around 30-50 \$US.

But, I guess we all make such mistakes.

Goran

Re: Basic circuit

I will not make a PCB, I would be happy if I could put all parts
together and if they work, I am really newby