Using an external iPhone battery with the USB power bit

joey 2014-09-19 21:29:17 UTC #1

This is really a two part question. First, is it feasible to use an external iPhone battery, such as those made by Mophie, to provide power to the USB bit?

Second, related question, how can I best determine how much power my circuit is drawing and therefore how long a battery might last?

Thanks,

-j

MR_STEAM 2014-09-20 18:15:36 UTC #2

Hey @Joey!

Sorry for the last piece of confusion> Definitely an error on my end. What is the amount of current provided by the External Charger? An external charger that provides 1 amp will work! Concerning the second question, it mostly depends on the circuit, how many bits used, and the type of bits used to determine the answer. Do you have a volt-ohm-meter by any chance?

Also, the battery is rated by amp/hour. The battery will last depending on the amount of current drained from the circuit and the battery's rated amp/hour.

MR_STEAM 2014-09-22 19:55:22 UTC #3

Hey @Joey!

Watch this video! It shoes you how to measure current within your littleBits Circuit. I'm sure you could test the current with the 3 pins at the end of the connector, as well! HDK KIT. It shows you exactly how to measure the current!

MR_STEAM 2014-09-30 19:48:53 UTC #4

Hey @joey!

Did you have any questions or input that you need to be addressed? I'm not sure if I was of much help in this topic!

manitou 2014-10-02 11:08:11 UTC #5

it would be nice if littlebits would provide a table with the power consumption of each of the littlebit modules.

MR_STEAM 2014-10-02 13:43:24 UTC #6

Hey @Joey!

What exactly are you referring to in terms of power consumption? Are you suggesting the current starting point to trigger a module? Or how much does a module drains in current?

manitou 2014-10-26 22:04:54 UTC #7

It would be nice for budgeting power to know how much each module drains in current. The info could be included in the "Product Specifications" section on each module's web page. Here are some current consumption numbers that I have observed.

bargraph 26.4 ma
number  19.47 ma
dimmer  0.64 ma
dimmer+servo (analog mode)  13.6 to 70 ma
dimmer+servo (pwm)  13 to 25 ma
dimmer+number+servo(analog) 0v 47ma,  1v 50-60ma, 2v 65-70ma, 4v 68-78ma, 5v 67-96ma
arduino 33ma   with bargraph on (d5 HIGH) 57 ma
cloudbit (low power,default, 247MHz) 280ma (155 ma "steady state")
cloudbit (hi power, 454Mhz) 402ma (steady 166 to 242ma)

More power info (revised) at
https://github.com/manitou48/littlebits/blob/master/power.txt

MR_STEAM 2014-10-27 16:49:05 UTC #8

Hey @manitou!

Great advice! This addition could definitely help others create new modules or possibly test current consumption of circuits! Thanks!

rory_littleBits 2014-10-27 17:22:10 UTC #9

Hi @manitou,
Here in the office, one of our engineers found two external USB battery packs that work well with littleBits. The first is the RAVPower RP-PB08. It has 3000mAH of battery capacity.

http://www.ravpower.com/ravpower3000gold.html

The second is the TeckNet Power Bank which has 15000mAH of battery capacity.

These battery packs will only work with the p3 USB power bit. I hope that helps!

MR_STEAM 2014-10-27 17:40:56 UTC #10

Awesome @rory_littleBits!

Hey @joey! I think this provide guidance for you, as well!

baselsalam 2017-02-09 08:18:24 UTC #11

I've documented the current draw of all the different types of Bits I have using my DROK USB meter:

I will add more bits as I come across them (it's pricey to collect them all!!)

Edit: created a separate thread here: http://discuss.littlebits.cc/t/current-draw-of-various-bits-tested/24803