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I have ran and powered my whole project from the USB programming port. It connects to my wifi quad copter and sends the take off and land instructions properly, while reading the range finders.

The board has a voltage regulator attached to the RAW pin that can take up to 12 volts. The battery on the quad copter that I've spliced into is 11.1v. The board when I connect it to the battery draws power and the red power led lights up. But the LED for a WiFi connection just blinks and flashes instead of firing up and connecting to the WiFi network.. I'm curious, should I get a 5v or 7v and use the vcc pin on the USB serial headers instead of the raw power pin.

My understanding of the information from AsyncLabs and linksprite information says that the RAW pin for input power is sufficient to run the project. Is this something I am misunderstanding?

The board:
http://www.linkspritedirect.com/product_info.php?products_id=26
which is a clone of:
http://asynclabs.com/wiki/index.php?title=YellowJacket_1.0#Pin_Usage

The sensors (3):
http://www.maxbotix.com/documents/MB1010_Datasheet.pdf

The quad copter:
http://ardrone2.parrot.com/

I've been stuck for about a week trying various ideas and short of ordering/waiting for new parts I've tried them all, including days of time spent searching the net.

Thanks for any help and I hope this is the right place,
Postholes
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I'm not sure the USB headers feed power outwards. How is the WiFi connected exactly? It should be getting power from the 5V line (pin) I would have thought.
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WiFi modules draw a lot of current.  The Arduino's on-board regulator is a linear regulator.  The higher the input voltage, the lower the output current can be.

Assuming your project consumed the full USB allowed current of 500mA, your regulator would be dissipating:
11V - 5V = 6V * 500mA = 3W

That's a lot for a surface mount regulator with no heat sink.  You might be able to get 1.5W out of it, so you're down to around 250mA, maybe less.

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The "Yellowjacket" spec (http://ruggedcircuits.com/html/yellowjacket.html) calls for a RAW input of 7V-24V 150 mA.  Looks like the voltage regulators on that model are significantly larger than the ones on your board.
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The voltage regulator installed on the RedBack is different than the one that is installed on the YellowJacket. The datasheet for the RedBacks voltage regulator says max is 12v, the YellowJacket was upgraded so they could use a beefier voltage regulator.

I am using the WiShield libraries from async labs UDPApp libraries to connect to the quad copters WiFi network. I am able to send formatted strings to the quad copter which are parsed by the quad copters on board software into flight commands.

The 5v and 3v pins near the USB header are output pins, the voltage regulator is on the RAW input pin. When the board is being powered from the 11.1v battery, it is only connected to the three range finders. When I have it going straight from USB it doesn't have the 11.1v power supply connected. So for testing and programming I am running straight from the USB and only the USB cable. When I plug it into the battery on the drone it is only getting power from the RAW pin and it isn't executing the WiFi software. Could I be throwing too much power at it? I would think that being within the ~7 to 12v range that it should be fine.

It is confusing me because it runs fine, sensors and program, through the USB only connection. But when I throw it onto the quad copter giving power through the regulated power input pin the board gets power, displayed by the red led, however never actually finishes initializing and running the program I've uploaded to it, displayed by flashing green led and no action from quad copter.

So I think my question is; should I drop the power down from the 11.1v battery to maximum current for USB, I'm guessing it's 5v but I admit I lack a whole mess of knowledge on the electrical side since I'm a software guy, and power the RedBack board through the Vcc and ground pins on the USB jumper pins? Would spending that money, the whole $4 maybe and time, solve my problem? My first attempt to fix the problem was commenting out all of the Serial statements in the program thinking that since the RX, TX, and DTR pins on the USB header weren't connected maybe it couldn't initialize because of a serial comm error, didn't work.

The YellowJacket is out of stock and there won't be anymore for quite some time, I originally had one but burned it out plugging the 11.1v into the 5v pin, which is the output pin. I knew it at the time, I just got confused and broke it. So I'm using the RedBack now.

I know this is a bit long winded, sorry about that, but I wanted to make sure I'm giving all the necessary data.

Why would it work through the USB and not through an alternate power that is in acceptable ranges?

Numbers from the battery:
"1000mAh 11.V
10C Continuous Discharge
Charge at 1A max"

Thank you guys for the help.
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You supply power to the raw pin from the battery and power to the arduino power jack of 11 volts this should work. If you could draw how you have these it would be easy to help you fix this
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The voltage regulator installed on the RedBack is different than the one that is installed on the YellowJacket. The datasheet for the RedBacks voltage regulator says max is 12v, the YellowJacket was upgraded so they could use a beefier voltage regulator.
As I already explained, voltage is not the only thing you need to consider.  You need to calculate how much power the regulator is dissipating.  The higher your input voltage, the more voltage the regulator drops, meaning it dissipates more power in the form of heat.   If the regulator gets too hot, it starts to shut down.

Drawing too much current through an on board regulator is the #1 reason that projects work with USB, but not with external power.
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Thank you James, I misunderstood your earlier statement.

Do you think if I just wire a voltage regulator from power supply to the board that would be sufficient in this case?
Do you think this guy would clean up everything if i just wire input and ground to battery and output to the input pin?
https://www.sparkfun.com/products/107

This is a diagram as I have been wiring it for actual use if it will help at this point:
http://i.imgur.com/b8jYZ.jpg

I went and bought a 7.4v 800mA lipo battery. I still have to charge it but hopefully in the morning I will be able to test this.
« Last Edit: December 24, 2012, 12:29:05 am by Postholes » Logged

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