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how are the pins on a ic numbered? Answered

i have been trying to make cylon light bar thing.
but it isn't working, all the wires an connections are done according to what is said and i asked my neighbour to have a look he is a electrician and he was surprised it didn't go as well.
its the NE555  i put it togther. looking down on the plastic.
1-| o  U    |-8
2-|            |-7
3-|            |-6

was that the wrong way? i have seen other circuit diagrams and the pin numbers where not like that.
thank you
oh and also is some solder non-conductive? and can you burn wires and make them useless?
i don't think i could have fried the chip i getting pro at quick soldering.



im a beginner to this electronic stuff my first circuit with more than led, resistor, capacitor. what is a cold-solder junction? and how do i fix that? thank you

A cold-solder junction is when you dont melt the solder enough and it looks cloudy. try takin the solder out with a soldering braid and retrying it.

If you suspect that soldering maybe the problem, then get a multi-meter that can measure resistance and check the resistance between each point; measure from end to end, so if you have a wire that goes from a battery connector to pin 1 of your chip, put one probe on the battery clip and the other on the leg of the chip - not on your solder joint, on the actual leg. If the resistance is between 0 and 2 ohms, then the connection is OK. Repeat for ALL possible connections. If you find any that aren't connected as they should be, then resolder them. If all connections are OK, then soldering is not the problem so you've ruled that out and can start looking for the problem else where. Be methodical and persistent and you will be rewarded in the end.

.  Not sure about your particular chip, but your "drawing" is the way every 8-pin DIP chip I've looked up was configured.

Only poor soldered joins may give problems. Burning the wire may give problems it should be clean and bright to solder successfully.

Look at the IC it will have a notch or a spot at one end. - Put that end upright. the numbering is now from the top left round to the top right. 1 to however number of pins you have.