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Bending a SIP package

J

JJ

Jan 1, 1970
0
Hi,

I have an IC with a 23-Pin SIP package (http://
eportal.apexmicrotech.com/mainsite/pdf/EX.pdf). The problem is that
the available package is vertical, and I need it horizental.
To solve this, I am thinking about, first, slodering the IC, then
bending it down. However, I am afarid that some of the pins might ge
disconneted, and the IC is expenisve.

Does somebody have some experince with this?

Thanks,
JJ
 
D

D from BC

Jan 1, 1970
0
Hi,

I have an IC with a 23-Pin SIP package (http://
eportal.apexmicrotech.com/mainsite/pdf/EX.pdf). The problem is that
the available package is vertical, and I need it horizental.
To solve this, I am thinking about, first, slodering the IC, then
bending it down. However, I am afarid that some of the pins might ge
disconneted, and the IC is expenisve.

Does somebody have some experince with this?

Thanks,
JJ

On occasion I create pseudo-SMD parts from through-hole parts.
For example, I'll take a 14pin dips and turn it into a SMD.

I've noticed that typically the metal used with IC's cannot handle
repeated bending before snapping.

After a single 90 bend, I wouldn't be surprised if under a microscope
metal tearing can be seen at the bend..

I'll guess you have 1 shot at getting the bend right... Once bent, do
not correct or adjust or these's increased risky of rips.

I prebend my parts before soldering to get the bend in the preferred
location and to get a 90 bend on a forming jig...

Just pushing over the part after soldering can have too much bend
radius..
D from BC
 
J

John Popelish

Jan 1, 1970
0
JJ said:
Hi,

I have an IC with a 23-Pin SIP package (http://
eportal.apexmicrotech.com/mainsite/pdf/EX.pdf). The problem is that
the available package is vertical, and I need it horizental.
To solve this, I am thinking about, first, slodering the IC, then
bending it down. However, I am afarid that some of the pins might ge
disconneted, and the IC is expenisve.

Does somebody have some experince with this?

Bending pins, yes. But I would bend the pins first, and
then solder. This will trap a lot less push and pull
between individual pins.
 
J

John Popelish

Jan 1, 1970
0
D from BC wrote:
(snip)
Just pushing over the part after soldering can have too much bend
radius..

The risk is having too little bend radius. Bending the pins
over a curved surface really helps distribute the stretching
forces along more of the pin,, rather than having all the
bend take place at the weakest point.
 
M

Meat Plow

Jan 1, 1970
0
Hi,

I have an IC with a 23-Pin SIP package (http://
eportal.apexmicrotech.com/mainsite/pdf/EX.pdf). The problem is that
the available package is vertical, and I need it horizental.
To solve this, I am thinking about, first, slodering the IC, then
bending it down. However, I am afarid that some of the pins might ge
disconneted, and the IC is expenisve.

Does somebody have some experince with this?

Thanks,
JJ

Use the old sip as a model and bend it in a hobby vice in between a couple
pieces of wood. You really have basically one shot so make it count.

And yes I've done this several times with 100% success.
 
D

D from BC

Jan 1, 1970
0
D from BC wrote:
(snip)

The risk is having too little bend radius. Bending the pins
over a curved surface really helps distribute the stretching
forces along more of the pin,, rather than having all the
bend take place at the weakest point.

There's a "just right" bend radius :)

I've pushed over some soldered parts with so much bend radius, I can't
get 90 deg..the part makes contact with the PCB and then springs up.
D from BC
 
J

John Popelish

Jan 1, 1970
0
D said:
There's a "just right" bend radius :)

I've pushed over some soldered parts with so much bend radius, I can't
get 90 deg..the part makes contact with the PCB and then springs up.

As I said, the bend should be formed in unsoldered leads
(using as much of the part that will not be soldered as
possible), so the part drops into the holes and lies flat
before it is soldered. The bend should not take place at
the point where the leads neck down to fit the holes, but
only at the wider part. Just as DIP lead frames are
pre-bent between the case and the necked down spot.
 
D

David L. Jones

Jan 1, 1970
0
Hi,

I have an IC with a 23-Pin SIP package (http://
eportal.apexmicrotech.com/mainsite/pdf/EX.pdf). The problem is that
the available package is vertical, and I need it horizental.
To solve this, I am thinking about, first, slodering the IC, then
bending it down. However, I am afarid that some of the pins might ge
disconneted, and the IC is expenisve.

Does somebody have some experince with this?

Thanks,
JJ

Bend and form the legs *before* you solder it.
And once bent, don't move them again.
Keep the pins in the staggered arrangement.
Make sure the device is physically attached to the PCB (or heatsink)
before soldering.

Dave.
 
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