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Product BOB-11044 | about 3 months ago

Thanks Mike. Indeed the proof is in the pudding so it depends where your customers install the board.

If anyone is interested in this issue for their own board designs compare Sparkfun’s to this one: http://www.ti.com/lit/ug/slou134/slou134.pdf

Also if you find you want lower distortion than 10% (at 1.4W) you can get lower distortion and higher efficiency with this chip by using a higher impedance speaker: 16-32Ohms. The volume wont be as loud though.

Product BOB-11044 | about 3 months ago

Nice chip. Can you please rev. the layout to avoid this problem mentioned in the datasheet: “Place the input resistors close to the TPA2005D1 to limit noise injection on the high-impedance nodes.”

You have the high-impedance nodes routed all over the place.

Product DEV-11098 | about 3 months ago

To save money, get more ADC’s and all the features of the 32u4 boards you will want to look at the teensy and adafruit’s 32u4 board. Adafruit just announced the Flora etextile platform based on the 32u4. There are also now 32u4 boards from Olimex and others…

Product DEV-10998 | about 4 months ago

Yes, to save money, get more ADC’s and all the features of the 32u4 boards you will want to look at the teensy and adafruit’s 32u4 board. Adafruit just announced the Flora etextile platform based on the 32u4.

Product SEN-10955 | about 6 months ago

No, that is the 10bit one. the 14-bit one is the MMA8451Q

*MMA8450Q:Xtrinsic Low-power, 3-axis Xtrinsic

*MMA8451Q:Xtrinsic 3-Axis, 14-bit

*MMA8452Q:Xtrinsic 3-Axis, 12-bit

*MMA8453Q:Xtrinsic 3-Axis, 10-bit Digital

The datasheets are remarkably similar and the core ADC is 14-bit so there must be some quality sorting going on?

Incidentally Matt your board also doesn’t follow the manufacturers guidelines w.r.t. nearby holes and centrality of the package.

Product SEN-10955 | about 6 months ago

Hi, Please rev. this to follow the manufacturers recommendations (i.e. 4.7k pullups, non central placement, no holes near package, traces off all pads) from AN4077.

Can you make one with the higher res. MMA8451Q too? It would be good to have the 5v regulator on there too like the competitive board from LongQi

Product BOB-10901 | about 6 months ago

Hi Nate: Basic is good. Adafruit is basic too: it does 3.3v like yours and level translation and 5v and it is the same price:

“This sensor is easy to use with any microcontroller that has i2c capability. It is 5 volt compliant so you can use it with 3.3V or 5V logic with no risk of damage. There is an onboard 3.3V ultra low dropout regulator so you can power it with 3.3 to 5.0V. However, if you can give it 5.0V that is ideal since the VIN voltage powers the IR LED and the higher the voltage you can give it, the more powerful it is.”

Product COM-10994 | about 6 months ago

I recommend reading the MSDS before use. One of the ingredients is allergenic which means you might want to turn down the Sparkfun hyperbole and not use it on clothing or fingerpaint with it.

Product DEV-10864 | about 6 months ago

Note that 802.3af uses a much higher voltage (48v) to safely deliver power (15W) over the relatively thin 100m lengths of Cat 5 cable. They establish a current limit of 350mA for CAT 3 and 600mA for Cat V cables. These limits usually assume the cable is maintained in good condition (i.e. within a wall).

Don’t expecta a cheap 802.3af solution soon from Sparkfun -the standard is rather complex to do right. You can however find relatively affordable modules by searching for “802.3af injector” and 802.3af receiver/splitter.

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Product COM-10994 | about 6 months ago

Note the resistance chart. This might better be called resistive paint. For conductivity try lessemf ’s copper based paint.