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Product DEV-11286 | about 9 hours ago

Mini USB is basically (though not officially) deprecated in favor of micro USB for new designs. It has a much longer useful life, it’s compatible with USB OTG, and in the next few years all the new devices you get will have it and not mini. The ‘crazy designers’ are the USB Specification authors and the designers working at major electronics manufacturers; this isn’t something that’s decided by or for hobbyists.

If your MicroUSB receptacles are getting pulled off/broken, you either need to superglue/epoxy them down to the board (common for connectors), surround them in an enclosure to protect them from stress/strain, or use different solder or soldering techniques.

Micro is slightly smaller than mini, but that doesn’t mean it’s only for ‘small and space constrained’ devices. It’s the new standard. Large devices like printers and hubs will probably continue to be USB-B, but everything else should be micro USB going forward.

Product COM-11089 | yesterday

Read the datasheet! Yeesh.

They’re 1mm pins, normal 22ga breadboard wire is 0.64mm in diameter. So a little thick, yes.

They’re spaced 15mm apart, which is 0.591 inches, approximately 0.6 inches. That should be close enough to make it fit; the pins are probably tin-plated copper which is pretty flexible.

However, note that the tolerances are pretty loose: +/– 0.1 on the diameter, +/– 0.5 on the spacing. You might get a part that doesn’t fit, e.g. 1.1mm pins and 14.5mm = 0.57" spacing. Make the holes 1.6mm diameter in any PCBs and any spec-compliant parts should fit. Those tolerances are so loose that I suspect the manufacturer was just playing it safe and the parts you get will all be better than that.

Product DEV-11286 | yesterday

It’s not yet been in stock.

This page is here for pre-orders.

Product COM-11218 | yesterday

Sgt_Lemming answered that question here:

The noise it makes tells me that this is not continuous but a very rapid pulse. Having pulled apart a similar device before (from a cheap Chinese “taser” torch) there is probably a small spark gap inside it which feeds the actual transformer inside the HV end. A continuous AC arc would hum at it’s frequency with out the “snapping” sound and a continuous DC arc just hisses.

Product COM-11181 | about a week ago

You’re correct that A0-A5 can be used for digital I/O, but there are quite a few pins which cannot be used for digital IO on most microcontrollers.

In no case can you use VCC or Gnd as I/O. This is obvious. For this chip, if you (sensibly) lump AREF, AGND and AVCC into this category, you lose 9 of the 44 pins to power and ground.

In most cases, at least some of the oscillator pins are only for connection to a crystal. For this chip, that’s XTAL1 and XTAL2. This doesn’t usually include timer inputs for RTCs.

This chip has some pins dedicated to USB functionality. Sure, there’s I/O happening, but this isn’t ordinary CMOS I/O. This includes D+ and D-, UVCC, UGND, UCAP, and VBUS.

As an outlier, many small chips let you use the !RESET pin as I/O. Of course, this means that you loose this easy way to get a clean reset and need to resort to soft resets on some multiplexed switch or complete power cycling, which may not be acceptable. This is usually bad practice unless you’re extremely space-constrained and have no room or use for a reset switch. Most every Sparkfun project does have room and have a need for a reset switch.

That all adds up to a total of 18 pins not usable as digital I/O, or 26 I/O available in this 44-pin package. This is in agreement with the statement from the datasheet:

• I/O and Packages

– All I/O combine CMOS outputs and LVTTL inputs
– 26 Programmable I/O Lines

News - SparkFun Gets a Subpoena | about 2 weeks ago

No, I’m leaning towards a more frequent purchase: It had 20 orders from Georgia between the dates of October 1, 2011 and March 6, 2012.

It included a Sparkfun PCB, so that narrows it down significantly.

My bet is on an Ardunio Pro of some kind.

Product COM-10213 | about 2 weeks ago

The two FETs are very different at low gate voltages. The RFP30N06LE has a threshold voltage of 2V or less, while the FQP30N06L has a threshold voltage of up to 2.5V. As a result, the former can drive more than double the current at 3.3 V.

Which parts are you currently stocking? I suggest that you remove the latter completely and only stock the former.

Product TOL-11219 | about 3 weeks ago

No.

I’ve contacted Link Instruments requesting some, and pointed them back here, but there’s currently no software that works with this hardware.

Osqoop is open-source oscilloscope software which could be made to work with this hardware if a driver was written.

Product PRT-10968 | about 3 weeks ago

The previous posts are incorrect. They are correct in that the I/O pins are rated for 5.5V (or 6V, in the “Absolute Maximum” section, but it’s generally best to limit it to normal operating values; ignore the ‘absolute maximum’ section on most datasheets if you want to play it safe). However, it will not function properly when the input voltage is higher than 4 Volts.

Check out the schematic: The output is connected to the input through an inductor and a diode. There is no way for the device to regulate the output voltage down; it’s only passed through the forward-biased diode. That would allow you to use about 5.5V as an input to get out 5.0V, but the part will not be actively “regulating”; sufficiently low output current would cause this to rise depending on the diode’s behavior.

Over 4V, you’re not using the regulator as intended. You won’t damage this device, but your noise levels and load regulation won’t be as good. That’s probably OK; Lithium batteries only have a brief period at their fully charged state during which they’re over 4V.

News - According to Pete: April … | about 2 months ago

Use the feedback menu to the right.