9 Nov
2011
9 Nov
'11
11:54 a.m.
On Nov 9, 2011, at 2:03 PM, Eric Smith wrote:
On 11/09/2011 07:25 AM, Keith Monahan wrote:
Exactly. We used the QuickSwitch parts (with a 1N4148 on the power rail to drop the
threshold) on lots of PCI cards to FPGAs which won't take 5v (which is most of
'em). Worked a charm. It was really more of a safety thing anyway, as I'm given
to understand that most modern PCs use 3.3v signaling anyway, but since the cards were
universally keyed, we wanted to be safe.
Of course, the same board also had to interface to PC-104, which definitely is 5v in most
implementations. The QuickSwitches came in handy there, too. :-) SSOP came in handy,
because having both interfaces ended up using a whole lotta chips in a pretty small
space.
- Dave
I'm anxious to build a PCB that is based
around a pair of these
http://www.ti.com/product/sn74cbtd3384
10-Bit FET Bus Switches With Level Shifting
for a level conversion app.
I sampled some, although there was only the .635 pitch 24 SSOP/QSOP version available.
What these parts do is not any different than other commonly available
"QuickSwitch" parts, such as those from IDT and Pericom, and you can get those
in many packages, including SO. Most of those do not have the diode internally, so this
TI part does save one component, but that wouldn't excite me enough to switch from SO
to SSOP if I didn't already want SSOP for some other reason.