Member #187451

Member Since: January 11, 2011

Country: United States

  • News - Why You Should De-Rate Ca… | about 7 months ago

    This is a pretty good writeup. Just today I completed a white paper on why some tantalum caps on an old design were failing short and why the same caps on a newer design were ok. It all boiled down to surge voltages and our protection scheme on the older design being borderline for most cases. The cool thing is that I got to revisit surge voltage, ripple current, and TVS vs MOVs (for protection devices).

    One thing I’ll add, for most space applications we almost use tantalums exclusively (and of course ceramic). But for low ESR and density the tantalums still rule. We won’t touch most electrolytic caps with a ten foot pole. Between the limited life at very high temperatures (if we must, we always select 105C rated or higher), and the very poor operation at very cold temperatures, our design review checklist for aerospace applications includes a check for absence of electrolytics. Now for my home projects that is a different story, the electrolytics are just much more cost effective (if you don’t need the operation at extreme temps).

  • News - Promoting Science When th… | about 7 months ago

    You guys at SFE are just awesome. Wishing you the best. And hoping some of our elected leaders get a clue of what is that they get paid for.

  • Product DEV-09476 | about a year ago

    I’ve run into a few things while using this, so I am posting this info in case someone runs into the same.

    First let me say that I tried unsuccessfully to upgrade the firmware on mine. I followed all the instructions and yet I turned it into a brick. Sparkfun was great and exchanged it for me (can’t give them enough credit for that). I am sure it was something I missed or did in error, but I do not have the heart to try this again.

    So here are the config of my unit as recived:

    • WIZ100SR/WIZ110SR Ver. 04.01
    • LOCAL IP ADDRESS : 192.168.11.2
    • SUBNET MASK : 255.255.255.0
    • G/W IP ADDRESS : 192.168.11.1
    • Default Telet Port -> 5000
    • Default Serial Baud -> 57600, 8-N-1

    To get this info, I connected the serial output to the PC and listened on the port during the WIZNET’s power-up. However, as configured from the factory you have no access to the serial port (you can only listen, but not control the device). To gain control of it (e.g. enable the serial port, re-configure, etc), you first set your PC’s ethernet port to something like this:

    • LOCAL IP ADDRESS : 192.168.11.1
    • SUBNET MASK : 255.255.255.000

    You then use the Configuration Utility to connect to the WIZNET and configure it as desired.

    To connect to a uC directly the connections are as follow (this has been alluded to before):

    • J2 -> +5V (output from power supply)
    • J3 -> GND (from power supply)
    • J4 -> TX (TX from WIZNET)
    • J5 -> RX (RX to WIZNET)
  • Product WRL-08452 | about 2 years ago

    Just noticed the IC is not available; the BOB is, but the IC by itself is not. Is Sparkfun not planning on carrying the IC anymore?

  • News - How do I beer? | about 2 years ago

    pure gold - kudos

No public wish lists :(