Tips for replacing LME49600TS on Legato

[mjock3]

Wondering if anyone has some helpful info on how to replace the LME49600TS buffer on the Legato?

Thanks

 

[theAnonymous1]

I wouldn't attempt it with anything but a hot air station. You can pick up a low end one on ebay for about $50...

Youyue 850D SMD Hot Air Gun Rework Soldering Repair Station 110V | eBay

For only slightly more you can get one that has a soldering iron as well...

2in1 SMD Rework Soldering Station Solder Iron Welder Hot Air Gun 852D 5TIPS ESD | eBay

You'll also need to pick up some solder paste to put the new buffers on.

 

[Juergen Knoop]

cut off the pins first with a sharp stanley or utility knife before using the hot air!

 

[mjock3]

I managed to get pins up. So are you saying I need the hot air gun to remover the main part from the circuit board? As well as to solder the new part?

Thanks for the tip on solder paste, didn't know it existed. 🙂

 

[mjock3]

Thanks for the links!

I wouldn't attempt it with anything but a hot air station. You can pick up a low end one on ebay for about $50...

Youyue 850D SMD Hot Air Gun Rework Soldering Repair Station 110V | eBay

For only slightly more you can get one that has a soldering iron as well...

2in1 SMD Rework Soldering Station Solder Iron Welder Hot Air Gun 852D 5TIPS ESD | eBay

You'll also need to pick up some solder paste to put the new buffers on.

 

[theAnonymous1]

Yes, you need hot air to remove them from the PCB and melt the new solder paste.

 

[mjock3]

Just ordered one. When it comes any idea what temp I should set it to? And then the nozzle size, should it be a bit smaller or??

Thanks again

 

[theAnonymous1]

You'll probably want to use the largest nozzle.

Hot air rework takes some practice to get right. I would suggest getting a scrap piece of bare PCB and some cheap TO-220 devices like voltage regs and practice soldering and unsoldering some first. You can go one step further and actually try and power up the reg after the soldering routine to see if it survived.

I can't say exactly what temp you will need; I don't know if lead free solder was used or what type of paste you will end up buying. It will need to be hotter to take them off then it will be to melt the new paste though. The datasheet for the buffers says a max of 260C for 10 seconds, though I find that's usually fairly conservative.

I have some LME49600 and the practice materials mentioned if you're interested, just send me a PM.

 

[Russ White]

Hot air rework is an art - it simply takes some practice and careful attention. 🙂