Looks like I'll be designing a bunch of things with relays in them in the near future.
And not just relays. Lots of relays. In particular, little telecomm-type relays, with gold-plated contacts for dry switching, as these are mainly being used to connect various instruments to many different signal sources / sinks.
Mostly: lots of them, and needing some attention to signal integrity. So: on a PC board.
There comes the issue of driving them. Only about 5V / 20 mA per, but ya gotta protect against the back EMF at turn-off, and of course there's the need for enough control signals.
Infineon makes this nifty-sounding chip, the TLE7232GS, or SPIDER. SPI interface to a 5V or 3V MCU; plenty of drive capability for my purposes; handles 8 loads in a 24-lead SSOP; nice diagnostic capability.
I haven't actually hooked one up yet. I did, however, just print the datasheet.
Attempts 1..4: print from Acrobat 9.4.7. Page 1 prints. Try again: page 1 prints. Try pages 2..32: nothing. Try pages 3..32: page 3 prints.
Grrr. Acrobat used to pull this kind of stunt all the time, with a Postscript printer (even on Windows). Except, then, the printer would usually spit out an error page; there was no printer error printed here. Since switching to Debian-testing, with the latest and greatest CUPS, this hadn't been a problem for a while.
Attempt 5: print from Okular. The whole document comes right out on the printer, no problem. But...
The paper is warped! For some reason, this particular datasheet came out of the printer kind of rippled, and hard to square up for stapling. This is not usual.
I hope all this trouble with the datasheet doesn't bode ill for my use of the actual chip... maybe I should have bought a couple of specimens in my last Digi-Key order, just to try it out. (Though that order was for a different project, and piggybacking other stuff on it would have gummed up my accounting system, such as it is.) Prolly oughtta order a couple on general principles; there'll be time to test 'em a bit before the current design is nailed down.
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