My Converter Dilemma (Pi-Head)

I scrapped the idea of making a LDO converter time ago, for the solution everyone prefers, a switched driver.
I found two candidates each one with its pro and cons. I need some feedback to help me decide what feature is the most desirable.

Both drivers are current regulated.

Converter 1 is Flexible:
It can accept any battery configuration from 2.4v to 9v and its efficiency is in average 70~75%

Converter 2 is Efficient:
It can accept any battery configuration from 1.8v to 5.5v and its efficiency is in average 90~95%

What would you choose?

Thanks


Pablo

I picked #1,
based on the fact that I only use Li-Ion cells.
and that would run off one well, as well as two.

The other one would only run on a single cell, and then going down all the way to 1.8V would be useless for a li-ion.

~John

I chose flexible but it's a hard question. Depends on the light.

Only picked this because I like lights that are 2xcr123a format, and the efficient wouldn't support that.

But if I was looking for a single cell light, I'd go with "efficient".

-tibim

Im with ticey.

I went with option 2. I'd love to run the light on 1x18650, which seems to be just "the business" these days. Also, the idea of burning 25% of my energy as heat before it hits the LED makes me think "Isn't this why I switched away from incans in the first place...?"


But I'll take some of that pizza, if you're offering.

Do they cost about the same?

Yep, cost is about the same, one important fact is that the pineapple is a 2x123 body, so if I go the efficient way it would rule out the natural combination: 2x123 primaries


Pablo

That does rather make your choice for you, Pablo. I voted for option 2 because I'm thinking selfishly, running an LED off four NiMH AA cells.

PEU said:

Yep, cost is about the same, one important fact is that the pineapple is a 2x123 body, so if I go the efficient way it would rule out the natural combination: 2x123 primaries

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That's not my natural combination!! A 2x123 tube, to me, usually means a 1x17670 or 1x18650 tube. :shrug:

john

Picked converter #2...

I mostly use single Li-ions, so that would suit my needs best.

I'm a single Li-ion type of guy myself as well.

1x17670 or 1x18650

I go for efficiency....the 20% difference is material and will be noticeable....IMHO.

WP

Pablo - I too prefer the single Li-ion option, so I am with jtice et al. KK

EDIT: This post does not accurately reflect my position. Sorry, it was late. What I meant to say is that I prefer option #1.

Nebula said:

Pablo - I too prefer the single Li-ion option, so I am with jtice et al. KK

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If you prefer a single Li-Ion, then you aren't with jtice! (Sorry John!) He wants it to be able to handle 2 Li-Ions, which would be require option 1.

jtice said:

I picked #1,
based on the fact that I only use Li-Ion cells.
and that would run off one well, as well as two.

The other one would only run on a single cell, and then going down all the way to 1.8V would be useless for a li-ion.

~John

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I picked the same for the same reason.

But I want a 5-topping pizza too damnit!!!

I'm a single Li-ion type of guy myself as well.

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Me too.
For LED flashlights, I prefer single Li-On's.

What we really want is option #2 with a drive range of 3V-8V and pizza.

Hallis said:

But I want a 5-topping pizza too damnit!!!

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Poll is multiple choice, you missed that :nana:

Keep the feedback coming! Thanks


Pablo

So PEU wheres my pizza? As for converters, you might try to up the range say, 3-7 volt range, just curious are you using a linear regulator? and you have to choose which one will be the most efficient?

65535 said:

So PEU wheres my pizza? As for converters, you might try to up the range say, 3-7 volt range, just curious are you using a linear regulator? and you have to choose which one will be the most efficient?

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My choices are:

TPS63000 (Efficient)
LT3477 (Flexible)

If you find something better Im all ears


Pablo

jch79 - I take your point, but still vote with John. Like John, I want to use Li-ion cells exclusively. That makes #1 the more appropriate option for my needs.

Sorry if my orignal post was confusing. I will edit.

Kirk

jch79 said:

If you prefer a single Li-Ion, then you aren't with jtice! (Sorry John!) He wants it to be able to handle 2 Li-Ions, which would be require option 1.

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