Cc3d Mini Spectrum Sat
« on: March 05, 2017, 09:41:14 pm »
Hi everyone I am new to the forum and I have a question about where to get the 3.3 voltage to power my satellite for my CC3D mini. When I purchased the mini I figured the satellite would plug right into it like its big brother version cc3d. Been searching around the forums and have found a voltage step down to 3.3 V. Do I need this or is there a way to wire in the satellite. Thanks

f5soh

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Re: Cc3d Mini Spectrum Sat
« Reply #1 on: March 05, 2017, 09:49:05 pm »
Hi, welcome.

DSM sat need 3.3V from SBL pad or directly from the regulator like here:
https://forum.librepilot.org/index.php?topic=3170.0

Please take a look at wiki page:
https://librepilot.atlassian.net/wiki/display/LPDOC/Setup+a+Spektrum+Satellite

Re: Cc3d Mini Spectrum Sat
« Reply #2 on: March 06, 2017, 01:32:25 am »
I'll take a look when I get home but i got a feeling the board is so tiny I won't be able to solder it. Is the schematic for the mini cc3d. What do I need to make a step down voltage to 3.3 V. Is there a part number or a website I can order one from. I apologize for being a noob and not searching around. It's hard to find accurate info on the web being open source software.

Re: Cc3d Mini Spectrum Sat
« Reply #3 on: March 06, 2017, 05:37:53 am »
The links @f5soh posted show you how to do it.

It doesn't need much current so just about any 3.3v voltage regulator will work as long as it can use 5v as the source (some may need a higher input voltage).

This would work as would a thousand others.  :)
http://www.ebay.com/itm/LM1117T-LM1117-Low-Dropout-Voltage-Regulator-IC-3-3V-/260830922293

Make sure what you get is large enough for you to solder.


Re: Cc3d Mini Spectrum Sat
« Reply #4 on: March 21, 2017, 02:40:10 am »
It showed up in the mail today. I need help on how to solder up mu input source voltage and out put and where is ground.

Re: Cc3d Mini Spectrum Sat
« Reply #5 on: March 21, 2017, 08:35:15 am »
The ebay listing has a link to the data sheet.  The end of the data sheet has some drawings of the various package types.  I think you got a TO220 type?

Here is a pinout of the TO-220 type from Googling
lm1117 pinout
http://datasheetcafe.databank.netdna-cdn.com/wp-content/uploads/2015/09/LM1117-Pinout.gif

1 - Start out with a two wire cable with the correct connectors on each side.  I assume it will be red for + and black for -.
2 - This cable will have an input side that is connected to the 5v source and a 3.3v output side that is connected to the receiver.
3 - Skin some insulation off the middle of the black / ground wire of the cable without cutting the metal wire.
4 - Solder that to the Ground pin on the device.
5 - Cut the red wire in the middle.
6 - Solder the 5v source side of the red wire to the Input lead
7 - Solder the 3.3v output side of the red wire to the Output lead.  Note that the Output lead is also connected to the metal tab part.
8 - Connect power to 5v input and measure the voltage at the output connector before connecting it to the receiver.
9 - Protect it from shorting out with heat shrink tubing or electrical tape

Ideally you would put small capacitors across both gnd to input and gnd to output, but the bare regulator has worked for some projects in the past for me.

Re: Cc3d Mini Spectrum Sat
« Reply #6 on: March 21, 2017, 07:25:21 pm »
Ok got it just to make sure so I don't short anything. 5v to the input. Output should be 3.3v. Then all the negatives going in and out of the voltage step down unit go to ground for say negative terminal on my power distribution board