Hi everyone,
i just designed an Arduino circuit on a breadboard, i would appreciate some help to figure out any problems, wrong wirings or improvements i could make in the circuit..
Thank you in advance,
zaxarias
Fritzing diagrams are generally horrible to follow, but I must admit, yours was not too bad to follow. That being said, I wouldn't wire it up as you have it in your diagram. You are daisey-chaining the grounds, which can push all the current of the whole circuit through one push in connection, and also bring much noise to every component in the line. Each ground and power connection should go to their respective rail.
tinman13kup:
Fritzing diagrams are generally horrible to follow, but I must admit, yours was not too bad to follow. That being said, I wouldn't wire it up as you have it in your diagram. You are daisey-chaining the grounds, which can push all the current of the whole circuit through one push in connection, and also bring much noise to every component in the line. Each ground and power connection should go to their respective rail.
Oh, you mean i should ground each component straight away to the ground trail of the breadboard?
Would it would really make a difference? 
Thanks for your answer...
You should common the ground pins right at the chip, not by going all the way round the board, thats
a massive ground loop. Ditto supplies, wire straight over the chip with short wires. But you do have decoupling
which is the most common mistake people make
And yes layout is important with logic chips, signals switch at slew-rates of >10^9 V/s. A ground-grid is a
good substitute for a ground-plane, so join the two ground rails at several places if possible.
Daisy chaining won't be much of a problem with a brand new clean breadboard, but in practice connections
tarnish, dirt gets in, springs weaken, its good practice to reduce the number of hops as much as possible.
Your 1117 also needs a ground connection. Your ground circuit ends at the output capacitor.
MarkT:
Ditto supplies, wire straight over the chip with short wires. But you do have decoupling
which is the most common mistake people make
MarkT thanks for your answer,
I don't really understand the meaning of "Ditto supplies".
Also what's wrong with the decoupling capacitors?
zaxarias:
MarkT thanks for your answer,I don't really understand the meaning of "Ditto supplies".
Also what's wrong with the decoupling capacitors?
Ditto supplies means same thing with the supply wires. Run a jumper from the 5v rail to the 7805, and another jumper from the rail to the 1117, and another jumper from supply to the IC...
Nothing is wrong with your decoupling capacitors. He said many people do not put them in and then wonder why they have stability issues.
tinman13kup:
Ditto supplies means same thing with the supply wires. Run a jumper from the 5v rail to the 7805, and another jumper from the rail to the 1117, and another jumper from supply to the IC...Nothing is wrong with your decoupling capacitors. He said many people do not put them in and then wonder why they have stability issues.
Thanks for your answer.. I got it!!!