General question about powering an arduino

[crenn]

Are you getting a raw ATMega328P or a preprogrammed ATMega328P with the Arduino bootloader?

[SXRguyinMA]

preprogrammed. I could have gotten either though as you can burn the bootloader through the arduino and it's software

[crenn]

You need an ISP programmer to burn the bootloader, you can't with just the arduino and it's software (however there is ways around that).

[SXRguyinMA]

Well I've got a programmer that will do ICs from 8-pins and up, I used it to write and program my lighting sequences to my PIC 12F683 on my RGB controller. But either way, I got one with the bootloader in it, so I'm all set. I just gotta try to figure out this funky relay thing. It's like it's leaking voltage backwards through the ground, through the PSU and then back through the 12v line and keeping the relay open. I may get a 5v relay and use the 12v to turn on the 5v and go that way, we'll see though.

[crenn]

The only solution I can think about is to use a 5v regulator to try to solve the problem, but I'm not sure how well that will work.

[SXRguyinMA]

alright I got my new chip in today and all is good. now I'm going to do some more sketching with that circuit simulator and figure out how to work in that 5v relay

[SXRguyinMA]

alright crenn what do you think about this instead? I'd need to get another diode but that's no biggie. could I use a transistor in this circuit instead maybe?

$ 1 4.9999999999999996E-5 1.6308177459886661 50 5.0 50
z 224 288 224 192 1 1.2 5.1
r 160 288 160 192 0 15.0
c 192 288 192 336 2 10.0 2.0885785848445715
c 192 336 192 400 2 10.0 2.0885785848445715
w 192 400 288 400 0
w 288 400 384 400 0
w 384 208 384 192 0
g 288 400 288 448 0
w 224 288 192 288 0
w 192 288 160 288 0
w 160 192 192 192 0
w 192 192 224 192 0
w 224 192 384 192 0
178 272 96 384 96 0 1 0.02 0.015625 0.05 1000000.0 0.0010 320.0
x 414 344 451 347 0 10 Arduino
x 437 42 507 45 0 10 5v to sense pin
w 384 112 384 192 0
R 224 128 176 128 0 0 40.0 5.0 0.0 0.0 0.5
r 384 64 464 64 0 10000.0
g 464 64 512 64 0
s 224 128 272 128 0 0 false
w 272 144 272 384 0
w 272 384 288 384 0
w 288 384 288 400 0
181 384 208 384 400 0 1205.7972822685413 100.0 5.0 0.4 0.4
w 272 96 272 64 0
w 272 64 384 64 0
d 272 128 272 96 1 0.805904783
o 2 64 0 35 5.0 102.4 0 -1
o 3 64 0 35 5.0 102.4 1 -1
o 24 64 0 35 5.0 204.8 2 -1

[SXRguyinMA]

or how about this? why do I even need the resistor and diode on the caps?

$ 1 4.9999999999999996E-5 23.47059216675035 54 5.0 50
c 192 272 192 320 2 10.0 2.440884490230046
c 192 320 192 384 2 10.0 2.440884490230046
w 192 384 288 384 0
w 288 384 384 384 0
w 384 192 384 176 0
g 288 384 288 432 0
w 192 176 224 176 0
w 224 176 384 176 0
178 272 80 384 80 0 1 0.02 0.015625 0.05 1000000.0 0.0010 320.0
x 414 328 451 331 0 10 Arduino
x 437 26 507 29 0 10 5v to sense pin
R 224 112 176 112 0 0 40.0 5.0 0.0 0.0 0.5
r 384 48 464 48 0 10000.0
g 464 48 512 48 0
s 224 112 272 112 0 0 false
w 272 128 272 368 0
w 272 368 288 368 0
w 288 368 288 384 0
w 272 80 272 48 0
w 272 48 384 48 0
w 384 96 384 176 0
162 384 192 384 384 1 5.0 1.0 0.0 0.0
w 192 176 192 272 0
z 272 112 272 80 1 0.1 4.9
o 0 64 0 35 2.5 0.8 0 -1
o 1 64 0 35 2.5 0.8 1 -1
o 21 64 0 35 5.0 0.8 2 -1

[crenn]

1st circuit: Won't work due to all the current passing through a single diode. That diode is going to have a voltage drop of at least 0.7 depending on the construction of the diode, if you can find a diode which can handle the current (around 1-1.5A) has a voltage drop lower than 0.3v, that will work (remember, you have to give the arduino at least 4.5v to work and the servo may require a little more.

2nd circuit: If your power supply can support a surge of 60+ amps on the 5v line, then the only problem would be the diode as it would be very unlikely to support 60+ amps.

[SXRguyinMA]

1st circuit: Won't work due to all the current passing through a single diode. That diode is going to have a voltage drop of at least 0.7 depending on the construction of the diode, if you can find a diode which can handle the current (around 1-1.5A) has a voltage drop lower than 0.3v, that will work (remember, you have to give the arduino at least 4.5v to work and the servo may require a little more.

2nd circuit: If your power supply can support a surge of 60+ amps on the 5v line, then the only problem would be the diode as it would be very unlikely to support 60+ amps.

ok so is that why I need the resistor and diode in before the caps? what if I put in just the 15ohm resistor and no diode? In the diagrams the diode doesn't seem to do much anyways, it all goes through the resistor