Flip IC´s pins

[rasco22862]

Hi, i made the LED Volt Meter from the electronic-lab web. I didnt notice that the PCB wasnt ready for transfer, so i etched a non- Mirrored PCB. OK, i found my way puttin the components, but how can i flip the ics pin without getting a NON-PIN-IC. I mean, is there a way to flip the pins, with another socket or something like that??

[MikeH]

2 things you could try:

1.  try soldering the IC to the opposite side of the board (good luck with this btw)
2.  carefully bend the pins of the IC up and install it upside-down.

[johngreene]

Hi, i made the LED Volt Meter from the electronic-lab web. I didnt notice that the PCB wasnt ready for transfer, so i etched a non- Mirrored PCB. OK, i found my way puttin the components, but how can i flip the ics pin without getting a NON-PIN-IC. I mean, is there a way to flip the pins, with another socket or something like that??

This used to happen quite frequently back in the day of hand-taped layouts. The solution was always to bend the pins of the ICs around and mount it in upside down.

There was this one PCB designer that I worked with that I never understood how he managed to keep his job because he had dyslexia pretty bad. Not only did he layout all the footprints for the ICs backwards, but he reversed all the 8 bit buses (bit 0 connected to bit 7, etc.). That was a fun board to get running. I think 3 of us were up all night working on that board. On top of that they decided to save a couple of dollars by ordering it without a solder mask and silk screen. No big deal except the assembly girl was used to being able to run the iron and solder along the IC in one continous motion. Not a problem if there is solder mask, but without it, just about every pin on the IC had a solder bridge to the adjacent pins.

Dang, that was 22 years ago and was completely out of my mind and I just relived it like it was yesterday. bleh.

--john

[petemoore]

  Try to pull the bend so it's apportioned over a small span, instead of being a 'hinge', these pins break off easily.
  another technique would be to pin the chip on a stick, and hook lead wires above the top of the chip, shape lead/pins for socket, very quick and easy with the soldering heat, pre-tin surfaces lightly, cool, then start final solder by heating the wire, maybe cool the chip with an ice cube before heating the pin.

[sfr]

I've soldered in resistor leads or break-away sockets with the plastic removed into the holes for the IC.  (standing up from the component side) and then set the IC, top down on the board inbetween these, and soldered each leg to the resistor leads. 

[mojotron]

For a while there I would actually sell stuff with the DIP packs upside down - I thought it would make reverse engineering more difficult.... I don't know about that, but I got over that once I accepted that my stuff was not revolutionary... Silly me.

[stm]

Like 20 years ago I bent back the pins on an MN3008 because I mirrored the PCB.  I always regretted it afterwards when I wanted to use the chip again.   I suggest soldering some wire leads that extend upwards the chip, and then solder these leads to the PCB with the chip upside down, as petemoore suggested.  This way you can undo the job with little or no damage to the chip.

Well, is it is just a simple opamp I wouldn't bother much. It's the NOS and rare IC's where you have to be careful!

[Mark Hammer]

I've made far too many mirrored boards to want to think about.  Depending on the chips in question, you can either bend the pins backwards...slowly....as suggested, or you can simply solder the chips to the board from underneath.  The "depending" implies the following considerations:
1) That the chip doesn't have TOO many pins.  A 16-pin chip has twice as many chances to fracture a pin during bending as an 8-pin chip.
2) That the chip is not one you might want or need to pull out of a socket or unsolder from a board to make another circuit functional.
3) That the chip is not so rare and expensive that any risk of damage is critical and intolerable.

So, a 4558?  bend it backwards.  A pricey Burr-Brown dual op-amp?  Maybe solder it to the underside without bending.  An MN3005 or SSM2040?  Maybe you should solder a socket to the underside first.

Any transistors that may be installed "wrong" can be installed on the component side,as long as you make a point of paying attention to the pinout.  If the pinout requires some sort of unholy twisting of the tranny (more likely to be true for FETs and "button"-type bipolars), then I would suggest slipping a piece of stripped wire insulation over the tranny leads to prevent any unwanted between-lead contact during the twisting.