Forums

MSOP to SO8 adapter

Started by John Larkin October 2, 2014
This lets us drop another opamp into an LT1124 SO8 footprint. LT1124
has a nonstandard pinout, so few subs are available.

https://dl.dropboxusercontent.com/u/53724080/PCBs/Z364_Adapter_2.JPG



-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

On Thu, 02 Oct 2014 13:50:17 -0700, John Larkin wrote:

> This lets us drop another opamp into an LT1124 SO8 footprint. LT1124 has > a nonstandard pinout, so few subs are available. > > https://dl.dropboxusercontent.com/u/53724080/PCBs/Z364_Adapter_2.JPG
Did that come straight from the board house that way? If so, did they whine much about it? If not, what did you get, and what did you do to it? -- Tim Wescott Wescott Design Services http://www.wescottdesign.com
On Thu, 02 Oct 2014 16:07:19 -0500, Tim Wescott
<seemywebsite@myfooter.really> wrote:

>On Thu, 02 Oct 2014 13:50:17 -0700, John Larkin wrote: > >> This lets us drop another opamp into an LT1124 SO8 footprint. LT1124 has >> a nonstandard pinout, so few subs are available. >> >> https://dl.dropboxusercontent.com/u/53724080/PCBs/Z364_Adapter_2.JPG > >Did that come straight from the board house that way? If so, did they >whine much about it? If not, what did you get, and what did you do to it?
They came just like that, no whining. We ordered 100 and they shipped us a couple hundred. We thought they might be panelized, like these older ones, https://dl.dropboxusercontent.com/u/53724080/PCBs/Break2.jpg but they routed them individually, somehow. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
On 2014-10-02, John Larkin <jlarkin@highlandtechnology.com> wrote:
> > This lets us drop another opamp into an LT1124 SO8 footprint. LT1124 > has a nonstandard pinout, so few subs are available. > > https://dl.dropboxusercontent.com/u/53724080/PCBs/Z364_Adapter_2.JPG
Why didn't you use flex? -- umop apisdn --- news://freenews.netfront.net/ - complaints: news@netfront.net ---
On 3 Oct 2014 10:16:49 GMT, Jasen Betts <jasen@xnet.co.nz> wrote:

>On 2014-10-02, John Larkin <jlarkin@highlandtechnology.com> wrote: >> >> This lets us drop another opamp into an LT1124 SO8 footprint. LT1124 >> has a nonstandard pinout, so few subs are available. >> >> https://dl.dropboxusercontent.com/u/53724080/PCBs/Z364_Adapter_2.JPG > >Why didn't you use flex?
Would that be better? -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
On 04-Oct-14 1:26 AM, John Larkin wrote:
> On 3 Oct 2014 10:16:49 GMT, Jasen Betts <jasen@xnet.co.nz> wrote: > >> On 2014-10-02, John Larkin <jlarkin@highlandtechnology.com> wrote: >>> >>> This lets us drop another opamp into an LT1124 SO8 footprint. LT1124 >>> has a nonstandard pinout, so few subs are available. >>> >>> https://dl.dropboxusercontent.com/u/53724080/PCBs/Z364_Adapter_2.JPG >> >> Why didn't you use flex? > > Would that be better? > >
I fitted some mod boards to some telecoms gear back in the 90s. Similar to your little board but it used a flex substrate. I cant remember whose gear it was, probably Nokia or Siemens. It worked ok out.
On 2014-10-03, John Larkin <jlarkin@highlandtechnology.com> wrote:
> On 3 Oct 2014 10:16:49 GMT, Jasen Betts <jasen@xnet.co.nz> wrote: > >>On 2014-10-02, John Larkin <jlarkin@highlandtechnology.com> wrote: >>> >>> This lets us drop another opamp into an LT1124 SO8 footprint. LT1124 >>> has a nonstandard pinout, so few subs are available. >>> >>> https://dl.dropboxusercontent.com/u/53724080/PCBs/Z364_Adapter_2.JPG >> >>Why didn't you use flex? > > Would that be better?
It'd be thinner. It looks kind of chunky in FR4. On a PCB of that size flex should be rigid enough. plus you can trim flex with scissors -- umop apisdn --- news://freenews.netfront.net/ - complaints: news@netfront.net ---
On 04/10/2014 10:43, Jasen Betts wrote:
> On 2014-10-03, John Larkin <jlarkin@highlandtechnology.com> wrote: >> On 3 Oct 2014 10:16:49 GMT, Jasen Betts <jasen@xnet.co.nz> wrote: >> >>> On 2014-10-02, John Larkin <jlarkin@highlandtechnology.com> wrote: >>>> >>>> This lets us drop another opamp into an LT1124 SO8 footprint. LT1124 >>>> has a nonstandard pinout, so few subs are available. >>>> >>>> https://dl.dropboxusercontent.com/u/53724080/PCBs/Z364_Adapter_2.JPG >>> >>> Why didn't you use flex? >> >> Would that be better? > > It'd be thinner. It looks kind of chunky in FR4. On a PCB of that > size flex should be rigid enough. plus you can trim flex with scissors > >
The 'thick' board makes for a nice strong solder fillet which is very easy to do, at least manually. I used this 'half PTH' method before, except in my case, the MSOP was mounted upside-down in a routed rectangular hole. If you're going to mess-up, do it properly. Cheers -- Syd
On 10/4/2014 11:09 AM, Syd Rumpo wrote:
> On 04/10/2014 10:43, Jasen Betts wrote: >> On 2014-10-03, John Larkin <jlarkin@highlandtechnology.com> wrote: >>> On 3 Oct 2014 10:16:49 GMT, Jasen Betts <jasen@xnet.co.nz> wrote: >>> >>>> On 2014-10-02, John Larkin <jlarkin@highlandtechnology.com> wrote: >>>>> >>>>> This lets us drop another opamp into an LT1124 SO8 footprint. LT1124 >>>>> has a nonstandard pinout, so few subs are available. >>>>> >>>>> https://dl.dropboxusercontent.com/u/53724080/PCBs/Z364_Adapter_2.JPG >>>> >>>> Why didn't you use flex? >>> >>> Would that be better? >> >> It'd be thinner. It looks kind of chunky in FR4. On a PCB of that >> size flex should be rigid enough. plus you can trim flex with scissors >> >> > The 'thick' board makes for a nice strong solder fillet which is very > easy to do, at least manually. > > I used this 'half PTH' method before, except in my case, the MSOP was > mounted upside-down in a routed rectangular hole. If you're going to > mess-up, do it properly. > > Cheers
Nice. Layout person now remembers to look for "top view" label. ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> writes:

> On 10/4/2014 11:09 AM, Syd Rumpo wrote: >> On 04/10/2014 10:43, Jasen Betts wrote: >>> On 2014-10-03, John Larkin <jlarkin@highlandtechnology.com> wrote: >>>> On 3 Oct 2014 10:16:49 GMT, Jasen Betts <jasen@xnet.co.nz> wrote: >>>> >>>>> On 2014-10-02, John Larkin <jlarkin@highlandtechnology.com> wrote: >>>>>> >>>>>> This lets us drop another opamp into an LT1124 SO8 footprint. LT1124 >>>>>> has a nonstandard pinout, so few subs are available. >>>>>> >>>>>> https://dl.dropboxusercontent.com/u/53724080/PCBs/Z364_Adapter_2.JPG >>>>> >>>>> Why didn't you use flex? >>>> >>>> Would that be better? >>> >>> It'd be thinner. It looks kind of chunky in FR4. On a PCB of that >>> size flex should be rigid enough. plus you can trim flex with scissors >>> >>> >> The 'thick' board makes for a nice strong solder fillet which is very >> easy to do, at least manually. >> >> I used this 'half PTH' method before, except in my case, the MSOP was >> mounted upside-down in a routed rectangular hole. If you're going to >> mess-up, do it properly. >> >> Cheers > > Nice. Layout person now remembers to look for "top view" label. ;)
My worst was a 208 pin 0.4mm pitch QFP that I decided should be 0.5mm :) -- John Devereux