You see those little dark cylinders in the image to the right? That's a ferrite core, they can come in any shape or size, if the image on the left is a choke the ferrite core is covered in an epoxy to keep the winding and core itself protected.

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Correct.
What you want to use is a coil with a larger diameter wire and a larger core. A larger ferrite core coil will pass a higher current than a smaller one before it saturates. Core saturation means that a coil rapidly loses inductance once the current going through it goes beyond a certain point. Core saturation in a switching power supply is a bad thing leading to poor efficiency and over heating. So remember to look at the current rating of the coil you are buying. Some will tell you the actual inductance to expect at the max recommended current rating.
Also, look at using a toroid core as these are self shielding.

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Oh, that's unexpected.
I've just looked from the local largest electronics part store, they have neither of them. Ceramic caps which is 1 uF and above and ferrite inductor.
I have to get them from farnell.
From farnell site, I found that ceramic disk they have less than 1 uF. I'm not sure what is ceramic multilayer. And, Tantalum Electrolytic, that is expensive.

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Look inside a worn out compact fluorescent light bulb. There are high current inductors inside. Try one.

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You mean break the bulb and find the coil inside? May the value be the same? I don't know and I'm just asking, the bulb is designed for 50 / 60 Hz and the boost converter is oscillating at 600 kHz, is it suitable? But I know that the frequency can be adjusted by C3 and R5.
It will be good if I can get the coil from the fluorescent light bulb, parts are not easily to be got over here

Thanks

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Compact fluorescent light bulbs have a 40kHz oscillator inside. The oscillator is made with many good electronic parts.
There are websites that show the schematics of many models.
Here is the schematic for a compact fluorescent light bulb:

Attached Images

compact florescent bulb.PNG (98.0 KB, 18 views)

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How accessible are these components though? I'd imagine they're at least mostly potted circuits? I've never tried to take a CFL apart before, but if the innards are actually usable I might buy a couple just to examine the internals.

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OMG, ferrite coil from farnell is not cheap! Not sure it takes how long to ship here, haven't ordered from them before.
I'm still looking for the fluorescent light bulb from my friends.

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I'm going to buy from farnell, the electronics shop has the catalog, so I can order from them.
Multilayer ceramic capacitor, I think this is what I need which is ceramic cap, but what is multilayer?
http://my.farnell.com/jsp/Passive+Co...questid=246667
http://my.farnell.com/jsp/Passive+Co...questid=246717
And the ferrite coil I've found is Ferrite Drum Core, is it suitable?
http://my.farnell.com/jsp/Passive+Co...questid=246728

I wanted to order the parts earlier, but I just got my salary this few days, and I can't order for only 1 unit for some of the products.

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DO NOT break the bulb of a CFL - they contain mercury! You can sometimes carefully wiggle the bulb enough to break the wires at the base and remove the bulb for safe disposal (preferably recycling). You can then pull the base apart to get to the electronics - and replace them with a driver for a proper LED bulb...

 

Oh just break it, but don't breath it! =) and make sure it's outdoors so what little is in there dissipates away from people/critters. You risk being close to it when it breaks by trying to break the base carefully. The real threat from CFL's and regular mercury lamps in the first place is the mass disposal of them. I work at a small company who disposes of full sized tubes legally by putting them in the dumpster and smashing them. We're a 'small quantity generator' and not regulated under the same laws as larger companies. It's illlegal for larger companies that dispose of multiple order of magnitudes more bulbs to do this though. A single large company doing this is equivilent to hundreds if not thousands of smaller companies and people. Destroying a single CFL for hobbyist is safe unless you do something stupid like crack the tube and try to snort the gas.

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I've smashed numerous fluorescent tubes and I've never seen a single drop of mercury leak out from them! I would estimate that even a large fluorescent tube probably only contains a couple of mg of mercury so I wouldn't worry about it,

Broken glass is probably the worst hazard and the phosphor probably isn't too good for you either. You don't always need to break the tube to get at the electronics, just saw round the base and they should fall out.

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A large 4' tube contains about 10-12mg for low concentration versions (down from about 50 in the 80's) and a standard Edison socket version about 5mg - which is more than a year's safe exposure. You don’t see it because in the vacuum of the tube, it exists as a gas. Now, you're not going to absorb all of that immediately with a cold bulb, and most will dissipate with ventilation in warm air temperatures. Where it will just be spread over a larger area and persist, or become the even more toxic methyl-mercury, until absorbed by somebody else. It also bioaccumulates in your body, so I would strongly suggest against a cavalier attitude about even small exposures. Some wise counties in the US have outlawed disposing of them in the garbage.
Sceadwain, if you keep smashing those tubes for another 20 years, you will indeed become mad as a hatter. Hopefully for your sake and everybody else's, LEDs will have replaced the Death Tubes long before then.
But I digress, if you do SAFELY (sawing around the base is probably the best option) open the base of the bulb, you may be able to recover usable components, but with the few I’ve opened, most of the components were burned or corroded and unusable.

 

multilayer is good - just means they've sandwiched multiple capacitance layers together to achieve that rating. you might want to consider tantalum capacitors, they are very common in smps circuits, the datasheet should recommend brands and model numbers known to work.

that still looks like an RF choke ... try searching for power inductor. at only 10uh, even a small power inductor will have a rating of several amps. Here's something good from Farnell's sister company Newark. Your datasheet will recommend what inductors to use, or at least what supplier and series to look at.

http://www.newark.com/jsp/Passives/I...sp?sku=27K6797

another, perhaps smaller in size

http://www.newark.com/jsp/Passives/I...sp?sku=63K3495

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OMG, I thought as long as they are ferrite inductor it will be working fine. I've ordered that After comparing the ferrite inductor with your recommendations, I found that the resistance of the inductor that I've order is more than 10 times compared to yours.
Those companies recommended from the datasheet don't supply to farnell, except Murata, but they have neither power inductor nor ferrite inductor for that value. So I tried searching on other company and I found this:
http://my.farnell.com/jsp/Passive+Co...questid=644948
This is the only 10 uH power inductor in farnell site.
Or this? It has low resistance.
http://my.farnell.com/jsp/search/pro...sp?sku=1077049

The product search in farnell's site is really messy, the inductor type is categorized as:
..
High current
Inductance
Inductor
Line reactor
..

Why these inductors don't even have value:
http://my.farnell.com/jsp/search/pro...sp?sku=1308790

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