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SparkFun Electronics will be closed on July 3rd, 2015 in observance of Independence Day. Any orders placed after 2:00pm MT on July 2nd will be shipped out after the weekend. Thanks!

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Sukhinov

Member Since: May 6, 2012

Country: Russia

  • In Russia we have similar m2m data-only SIM-cards with unlimited data traffic, claimed worldwide-roaming, but speed is limited to 4 kilobytes/second. The main difference is price: our SIM-cards are free (!) and require $1/month payment. So, this offer from T-Mobile seems very expensive.

  • OK, I see in the TPS61200 datasheet that there is a hysteresis on undervoltage lockout threshold. So, the possible scenario is following: battery discharges down to 2.6 v, the device turns off, then the battery voltage goes up to 3.2 volts since there is no load.

    Am I right?

  • I just checked the unit I have received and found that it has 3.2 volts cut-off voltage, not 2.6 as written here. When battery level is below 3.2 volts there is zero at Vcc. That is very good since 3.2 volts is best cut-off voltage for battery I have.

    I still curious how that may happen.

  • OK, replying to myself. This looks like SAW filter.

  • What is inside this metal thing?

  • Pretty sophisticated devices

    That is why credit card skimmer kit would be a great idea.

No public wish lists :(