increasing the voltage of a single cell.

[tommyboy64]

Has anyone seen a diagram or read an article on how i can increase the voltage from a single battery cell to about 5 volts.
I saw somewhere this was done. I can find it now.

Tom :cool:

[Graham Stabler]

What you need is a dc to dc converter chip and a few other bits. For low current apps I can recommend the LT1615 form linear technology www.linear.com. (http://www.linear.com.) It works down to less than a volt and can produce upto 34v on the output but this is selectable. Its a lowish frequency device so pcb layout isn't too critical and its really small. All you need to complete the circuit is a diode an inductor a couple of resisters and a capacitor or two. The web sie has data sheets. I don't work for linear but I do use this chip in my infra red receivers to fly 2 cell models. Other manufacturers do similar stuff. I can make you one if your not electronically inclined. Whats it for?

Graham

[corey c]

Hi, I to was looking for info on this dc\dc converter,thanks for the info. I can probably do this my self but I was just wondering how much you would charge for a ready built one?

[Graham Stabler]

probably about ten english pounds according to my spreadheet of components prices. Possibly a little less. Just remember it is a low current device.

[corey c]

do you think it work with n-20 motors or pager motors? I think they draw about 1/2amp. Do you mind if I ask what flight system you have[rx,motor,esc,actuators,sevos etc.] and how you have it set up?

[tommyboy64]

I am really glad someone finally replied. I am using it for a small plane similar to the Flying aces. I would like to use one small 3 volt tadrian cell or possibly 2 110 nicke hydrides and boost it to 6 volts. I will be using a n-20 with 4.2/1 gears. I believe this draws less than one amp. I am not real good at electrical things but i can figure things out and learn. How much would it cost to throw one of these devices together?

Thanks
Tom

[Graham Stabler]

My system consists of a Ztron ir receiver for magnetic actuators and a DC-DC convertor on a single pcb. It also has the esc on the same board. I use this with two 50mAh cells driving a KPOO direct drive. The DC-DC is only used to produce the 5v for the electronics, the KP00 runs from the two cells. This is installed in a sixteen inch wingspan depron high wing model based on plans I downloaded from the web. AUW 25g. At the moment I use a single home made bird style actuator for proportunal rudder control. I sell the receivers for 25GBP and the coils and magnets for making the actuators for 5GBP.

If you want to drive a motor you will need a higher capacity DC-DC converter. I'm going to try national semiconductors www.national.com (http://www.national.com) LM2621, this works down to 1 volt and 0.9volts once started. I has a small eight pin package and looks quite nice.

[Graham Stabler]

the 2621 is upto an amp. If you are using more than one cell then there are lots to choose from. As for these ones I don't know, if they say they can deliver an amp and the input range is ok for you then it will probably be ok. Getting hold of one might be difficult, I don't know. You must also remember that the current capabilities of these units seems to be a function of the step up size. A one amp rated unit will often say in the data sheet that it can provide 300mA with 5v out and 3v in. Thats my understanding anyway. I suppose they can't work miracles. Just try it!! Especially if you can wangle a free sample.

[tommyboy64]

Most of these chips only have an output of up to 500mah. Do you think this one that is rated up to 1ah will do the trick? http://www.toyomura.com.hk/icp17.htm

chip # s-8341

Tom
:cool:

[tommyboy64]

I found the article. 2xrien is the plane that utilized the step up unit. The Frenchies who designed it gave go detail on the components used.
Tom

[Graham Stabler]

I am an aeronut, www.aeronutz.free-online.co.uk (http://www.aeronutz.free-online.co.uk)
we have been doing a lot of stuff with DC-DC and one of the members Chris has been having success recently with a DC-DC converter to drive a KP00 or pager motor from one cell. He has made a foam plane with throttle and rudder down to a weight of 15g and it could be lighter. I'm not sure what chip he uses but I might be able to find out. The beauty of using a pager motor with DC-DC is that they go better at the high voltage but still only need a low current. The moins rien also uses a DC-DC but all the pictures are blured and no specific details, why not email them! Frenchies, we'll be saying yanks and ****** soon :D

[Graham Stabler]

just for the record I wasn't swearing. I don't know why the word has been starred out as it was another word for an englishman referencing the amount of limes eaten by english sailors. Puzzling

[tommyboy64]

Thanks for the link to your sight. It really has some good ideas. You Europeans are really on top of this small stuff. I still havent got to the electronic store to find a suitable chip. I never new that there are so many chip makers in the world.
I am going to pick up a pager motor also for experimentation. I didn't know that ***** was bad word. :confused: I hope to have my plane flying tomarrow. I am suprised there isn't more in this site on battery voltage conversion for a reduced # of cells. This seems kind of elementry for a light plane.
Tom
from sunny hot california

:cool:

[corey c]

with one of these converters on one 50mah, how long does it power the electronics for before re-charging? And would this power my mx-6800 rx and two mx-30 servos?

[tommyboy64]

Gee Wiz i dont know how long. Probably about 1 minute with only one 50 amp cell. There are other single cells with much higher capacity. I plan on using either 2 of the hydride 170 mah 1/3aaa or one of the small 3 volt tadrians boosted up to 6 volts.
I have been searching and the only chip i can find that fits the bill is the national chip. If you find another please let us know.


Tom

[pogcarr]

Seems that a ***** programmed the content filter! ;)

[jlcrl]

Hello,I am a 'frenchie'. Thanks for the '********', but nothing is hidden and a detailed article in 8 pages with very good pictures isavailable from the french RCM magazine.(RCM Nr 230 and 231: writeto 'ELT, anciens numéros RCM, rue du chateau, Tilly, 77310 St Fargeau'send 24F for each number= 48F). However, members of the 'french team'
always reply if you have questions. J.Y. Martin don't use the KP00 (current draws = almost 1A) but pager motors (so he use circuit you spoke about but there is an astuteness for the 'moins que rien voltage converter)
He tested tens and tens pager motors and finally he selected one for each category of weight.For the 20-35g,they draw 200mA and you can fly more than 12 minutes with 3 Nicad 50 maH.One pager (2g weight, 15g thrust under 4V with 22:1 gearbox and a 24/10 carbon propeller) is enough for a 28g plane, and 2 over 30g. I saw a 28g motor-glider (motor = 1 pager) climbing 4 times up to the top(15-20m)
of the exhibition centre of Paris (2 cells with voltage converter).
Motor (mounted with gearbox) are now avalaible from J.Y. Martin (jymartin@eurofeedback.com) and
the other parts (micro 0.4g ESC, 1.9g receiver, pic12c508 for actuator control and voltage converters) from J.M. Piednoir (jpiednoi@club-internet.fr)