Electronics > Projects, Designs, and Technical Stuff

Reflow TQFP without stencil?

(1/6) > >>

cyberfish:
Has anyone tried reflow soldering TQFP (or similar small pitch footprints) without a stencil, and just apply the paste with syringe?

How did it turn out?

I already have my PCB made, and trying to decide if I want to get a Pololu plastic stencil for it.

Thanks

djsb:
Just hand solder it. You can apply tacky flux, place the part and line it up. Then solder one of the pins on each corner. Apply some solder to a suitable bit and drag solder the remaining pins. Remove any excess solder with solder braid. Clean up.
Or use hot air with a small jet. ( with temperature/flow adjustment capabilities)
- Use flux to coat all of the ic's pads on the pcb.
- Put some solder on the tip of the soldering iron and drag it regularily across the ic pins.
- Use flux again to coat all of the ic's pads on the pcb.
- Place the IC on the board on top of the solder and fix it at 2 corners
- Use the hot air and heat the pins while pressing down the device weakly



David.

TopherTheME:
I dont even use flux when soldering TQFP chips. I just align the chip and drag a tinned iron across all the pins. Then do a little clean up with and braided copper and the chips good to go.

mikeselectricstuff:
Although you can do without, Flux really does make things easier when using solder wire (as opposed to paste).
My normal way of hand-mounting a TQFP is to put a line of paste along each pin row on teh PCB, place & align the decive on top,  tack a couple of corner pins with a fine tip, then use a full-width blade bit to flow each side in one - place the the bit on the pins, then drag it away from the chip body to draw excess solder off with the bit. 

cyberfish:
Thanks

I guess it comes down to solder wire and solder paste then. Anyone done both? How do they compare?

Navigation

[0] Message Index

[#] Next page