Tiny SMD alignment tip

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Soldering these PCM5122 IC are fun depending on your definition of fun.
Here's my way of keeping them aligned while working with them.
I have included into the PCB design, through holes, that are attached to the SMD pads of each corner. In this way, one can slightly bed some leads of a spare through hole part (resistor shown) to fudge it into place and tighten it into position for working. This is my second go around with this method and intend to use some silver solder on the corners to weld it into place, then solder paste or lead based solder using a hot plate. this way, the silver will keep it's position without melting, while the other lower temp solder does its stuff.

cheers

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Apply flux to all the lands on the pcboard. Fit the SMD chip and centre it on the lands. Solder pin1, (with Lead Free Solder) whilst applying gentle pressure to the top of the component with a pair of tweezers. Check the pin alignment and if OK solder the opposite corner pin, (if a 16pin chip, solder pin9, 120 pin chip pin25, pin50, pin 75 the pin 100 etc).
You can then solder the rest with ease.
If you use flux, use a standard soldering iron with a puddle of solder and apply solder to 3 or 4 pins at a time, even more when you are used to the system, drawing the bit away from the pins when wet with solder. Makes a perfect joint, every time.
The secret is in the flux.
Don't rely on the core in the solder!
 
I always use a hot air gun. I apply a small puddle of solder on the lands with an iron and apply some flux to the contacts of the chip. Apply heat to the board on the outer edge of the puddles to heat the board. Center the chip on the puddles and apply more heat. When the solder liquefies, it will draw the chip in place. Works fine for me..
 
Apply flux to all the lands on the pcboard. Fit the SMD chip and centre it on the lands. Solder pin1, (with Lead Free Solder) whilst applying gentle pressure to the top of the component with a pair of tweezers. Check the pin alignment and if OK solder the opposite corner pin, (if a 16pin chip, solder pin9, 120 pin chip pin25, pin50, pin 75 the pin 100 etc).
You can then solder the rest with ease.
If you use flux, use a standard soldering iron with a puddle of solder and apply solder to 3 or 4 pins at a time, even more when you are used to the system, drawing the bit away from the pins when wet with solder. Makes a perfect joint, every time.
The secret is in the flux.
Don't rely on the core in the solder!

Why is it that almost all soldering issues come down to

"use more flux!"

;)
 
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Confession here...

I used low-temp paste and a slab of aluminum plate on the stove and it worked wonderfully.
Had issues using iron and any type of solder and also toasted the PCM using regular lead free paste.
Literally set the PCB with the DAC and low temp paste down on the plate and it was done in about 10 seconds. It looks and works perfectly. Totally pleased. Didn't even use the holes that I put in it other than it helps to eyeball it into position. I am an instant pro with low temp paste.

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