3mm 1.5V bright LED

[Man-wai Chang]

Is there such a toy?

--
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[Ian Field]

"Man-wai Chang" <toylet.toylet@gmail.com> wrote in message
news:j8e0kr$ttb$1@dont-email.me...

Is there such a toy?

Yes if you use a 1.5V blocking oscillator.

 

[bw]

"Ian Field" <gangprobing.alien@ntlworld.com> wrote in message
news:zoEqq.6082$gS1.1219@newsfe17.ams2...

"Man-wai Chang" <toylet.toylet@gmail.com> wrote in message
news:j8e0kr$ttb$1@dont-email.me...

Is there such a toy?


Yes if you use a 1.5V blocking oscillator.

http://cappels.org/dproj/ledpage/leddrv.htm

 

[Man-wai Chang]

Yes if you use a 1.5V blocking oscillator.

http://cappels.org/dproj/ledpage/leddrv.htm

I want one that has the (over?) driver built into the LED...


--
@~@ You have the right to remain silence.
/ v \ Simplicity is Beauty! May the Force and farces be with you!
/( _ )\ (Fedora 15 i686) Linux 3.0.4
^ ^ 13:36:02 up 11 days 17:42 0 users load average: 0.01 0.02 0.05
不借貸! 不詐騙! 不援交! 不打交! 不打劫! 不自殺! 請考慮綜援 (CSSA):
http://www.swd.gov.hk/tc/index/site_pubsvc/page_socsecu/sub_addressesa

 

[Ian Field]

"Man-wai Chang" <toylet.toylet@gmail.com> wrote in message
news:j8grkj$28m$1@dont-email.me...

Yes if you use a 1.5V blocking oscillator.

http://cappels.org/dproj/ledpage/leddrv.htm

I want one that has the (over?) driver built into the LED...

Some time ago Elektor did a front cover freebie; a tiny PCB with a dedicated
LED drive chip and inductor for voltages down to 0.9V - that's probably as
small as it gets.

Can't remember details but if you google Elektor and click contact from
their home page, you can ask the editor.

 

[Spehro Pefhany]

On Fri, 28 Oct 2011 18:37:15 +0800, the renowned Man-wai Chang
<toylet.toylet@gmail.com> wrote:

Is there such a toy?

You could use this simple circuit to work down to <<1V --


FB = OUT for Red

FB = GND for Green/Blue/White
|
.----------.
Vin 0.8V minimum | FB |
10uH | |
___ | L6920 | LED
o----+---UUU----|LX OUT|----+->|---+
+ | | | | |
--- | | | |
--- | REF | | .-.
47uF | '----------' | | |
| | + | |
GND 100n --- --- '-'
--- 47uF --- |
| |
GND GND GND


All the parts can be tiny SMT components. Reduce the 47uF caps to 22uF
and use 0805 22uF/6.3V ceramics and an 0805 inductor to reduce size,
and the 100n can be an 0402.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Ian Field]

"Man-wai Chang" <toylet.toylet@gmail.com> wrote in message
news:j8grkj$28m$1@dont-email.me...

Yes if you use a 1.5V blocking oscillator.

http://cappels.org/dproj/ledpage/leddrv.htm

I want one that has the (over?) driver built into the LED...

http://www.elektor.com/magazines/2006/november/pr4401-led-driver.58609.lynkx

 

[Spehro Pefhany]

On Sat, 29 Oct 2011 22:39:27 +0100, the renowned "Ian Field"
<gangprobing.alien@ntlworld.com> wrote:

"Man-wai Chang" <toylet.toylet@gmail.com> wrote in message
news:j8grkj$28m$1@dont-email.me...
Yes if you use a 1.5V blocking oscillator.

http://cappels.org/dproj/ledpage/leddrv.htm

I want one that has the (over?) driver built into the LED...


http://www.elektor.com/magazines/2006/november/pr4401-led-driver.58609.lynkx

Presumably this part?

http://www.prema.com/pdf/pr4401.pdf


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com