Can spektrum AR6100 run on one cell?

[mayday1]

I've heard that AR6300 nano can be converted to run on a single cell
by changing a regulator chip, but searching the forum for what
exactly needs changing yields nothing.

I don't have any AR6300, but have a couple of AR6100, can they
be converted to run on single cell? Although AR6300 is lighter,
the funky micro JST servo connectors are hard to work with and
come by, so I am willing to give up a couple of grams for the
convenience of normal servo connectors.

Thanks for any info on converting spektrum to single cell use.

[Tomapowa]

Not too sure on a receiver mod but here's a few DIY solutions that should work with one LiPo cell:
(boost regulator design dependent upon proposed max current draw...)

http://www.ladyada.net/make/mintyboost/process.html

http://datasheets.maxim-ic.com/en/ds/MAX848-MAX849.pdf

http://www.linear.com/pc/productDetail.jsp?navId=H0,C1,C1003,C1042,C1031,C1 060,P80945

http://www.national.com/pf/LM/LM2698.html

[David T]

I'd expect Spektrum to be using settings in their design which requires 3.0v (the internal oscillator threshold for 3MHz and above). Their regulator has a 0.1v dropout so I'd expect no risk with lipo voltages down to 3.1v. It's likely to work fine lower than this too but will start becoming flakey.

The main challenge with 1lipo is that lipo voltages fluctuate very willingly under load. You can observe some of this behaviour with a voltmeter but a scope reveals greater voltage oscillations. These are extremely quick but can go below the 3.1v I mention long enough to disturb the Spektrum chips. You can compensate with an addon capacitor. All depends on your application/risk/stability required.
dt.

[Tomapowa]

Just ran across this cool 1-cell (LiPo) 5V-booster.... cheap too (<$5).
Limitation to be concerned about though is current... 1.5A max.

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7884&Product_Name=Voltage_Booster_for_BEC

[olmod]

I've heard that AR6300 nano can be converted to run on a single cell
by changing a regulator chip, but searching the forum for what
exactly needs changing yields nothing.

I don't have any AR6300, but have a couple of AR6100, can they
be converted to run on single cell? Although AR6300 is lighter,
the funky micro JST servo connectors are hard to work with and
come by, so I am willing to give up a couple of grams for the
convenience of normal servo connectors.

Thanks for any info on converting spektrum to single cell use.
The chip used is a MCP 1252 and was used in a AR6100 as a 1sp conversion , cant remember wich thread :o

[Tomapowa]

The chip used is a MCP 1252 and was used in a AR6100 as a 1sp conversion , cant remember wich thread :o

Doesn't that only supply around 120mA?
(http://www.rcgroups.com/forums/showpost.php?p=8151098&postcount=3)
This would not be an issue if that supply was only being use to power up the receiver circuitry but powering/controlling servos could be an issue...

[mcross]

Here's a link to the post: http://www.rcgroups.com/forums/showpost.php?p=11328008&postcount=110

I'm not positive about this but...
Servo power still comes from the +/- rails, so you'll have to use 1 cell servos. The MCP 1253 powers the stuff that the removed reg. was powering, the stuff that can't handle the 5 volts from the BEC.

Edit: the linked post uses an MCP 1253

[mayday1]

Just ran across this cool 1-cell (LiPo) 5V-booster.... cheap too (<$5).
Limitation to be concerned about though is current... 1.5A max.

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7884&Product_Name=Voltage_Booster_for_BEC

Bought two of these. 4.4gr each, 3.9gr without the heatshrink. I
fed them 2.6V to 4.3V, one of them maintained 5.00V (no load),
the other maintained 4.98-5.00V (no load). I didn't hook up a scope
to see what the ripple looks like.

I found that theSteve modified spektrum's internal 3pin linear voltage
regulator with a 3.3V buck-boost 5-pin regulator that provides up to
120mA. For really lightweight, that is the way to go. I'd just power
the receiver with it, and let the servos run on one cell raw to not
over tax the buck-boost regulator.

[olmod]

Here's a link to the post: http://www.rcgroups.com/forums/showpost.php?p=11328008&postcount=110

I'm not positive about this but...
Servo power still comes from the +/- rails, so you'll have to use 1 cell servos. The MCP 1253 powers the stuff that the removed reg. was powering, the stuff that can't handle the 5 volts from the BEC.

Edit: the linked post uses an MCP 1253
Thanks for the backstop :) there are a few servo's that are happy on low voltages.