Burr Brown Opamps coming this week OPA627/637

[FastEddy]

KP11520: " ... The shame here is that TI has forced many to look "Elsewhere" for the 627s in DIP. They won't be making any, from what they have said, until Spring 2008 ..."

A part of the reason for this is that the single channel '627 in the TO-99 can and its suggested PCB layout will result in better specifications (especially CMRR, noise rejection, etc.) than the 8-pin DIP physical layout will allow (there is just not enough room around the input & output to make that cute little shielding ring). Take a look at page 11 of the .PDF docs for clarification ...

 

[KP11520]

Hi FE,

I guess that is great for new designs with even better specs, but for the modding community (especially beginner types like myself) this could be considered a disaster!

Even kits and premade PCBs for headphone amps, etc. all want the DIP package!

I guess this is where creativity has to supercede common sense! YIKES! I have to see if I can find some, somewhere (common sense that is).

Regards//Keith

 

[FastEddy]

KP: I once took an 8-pin DIP socket and bent the leads of a TO-99 can so they plugged into the socket, then soldered the socket into the PCB ... worked fine, it just didn't look too "store bought" ...

 

[KP11520]

That's not so bad! I've seen pictures here of all kinds of rigging, so that is nothing. Pinout the same for pins 1 through 8? Since it is in a "metal can" is there any way to ground it to reduce RF affecting it (if it does or can anyway)? The "metal can" probably helps dissapate heat better too. Are the components in the "can" higher quality than the 8 pin DIP?

Thanks for showing me alternative ways!

Regards//keith

 

[FastEddy]

" ... Pinout the same for pins 1 through 8? ..."

NO!! Not necessarily, be sure you check to be sure ... (The op-amp I used was not the '627, but a much lesser variety and if memory serves the pins were difficult to get all of them bent so it would work.)

 

[eplpwr]

Verified fakes

Well, I bought 50 pcs OPA627AP from Effect Connection last summer (26th of June, 2007). Not until now have I've take the time to measure the chips, and this is what I get:

 

[eplpwr]

Measurement of real chips

This is what a real OPA627 looks like (just like the datasheet).

BTW, I've measured 10 of the fakes with consistent results, and about 5 pcs of real OPA627AP/BP's.