|Dec20-12, 08:08 PM||#1|
Did I just fry my IC555 ??????
Hi, 1st time poster, long time student/hobbiest of math, physics, most sciences. Just getting serious about electronics lately so I made my 1st 555 circuit ever
I made this blinker , it's a short vid with a very simple schematic in it, he draws it as he goes towards the end. I'm using 5V from an old printer PSU, I used 2 series of 2x 4.7kΩ, the circuit only uses "capacitance" in one place.
I had it working fine and I was trying different capacitors and series/parallel caps.
Then I put a 33kΩ between the neg side of the single cap and pin 1 of the 555 (should of had it before the cap to make a little RC series), and it blocked the current almost completely.
So I took it out and now the circuit won't blink anymore. If I place a short where the cap goes (between pin 1 and 2) the LED lights up and says on. But if I use a cap, the LED lights up for the correct amount of time, but never comes back on. Then if I reverse the cap (not ideal I know), the LED will light up for the correct time.
So I can get the LED to light for the right time, but it never comes back on.
The resistors all still measure correctly, so what happened?
|Dec21-12, 07:30 AM||#2|
Replace the IC. If the new one works where the old one wouldn't, I leave you to draw your own conclusions .....
|Dec21-12, 08:13 AM||#3|
only 1 I had, I made another 555 circuit and it doesn't work right either
So I'll have to make some 741 circuits, at least I have a few of them