Help identifier component 3 pins TO-92 chip

Q

Quim

Guest
Hello

It is one chip mounted in a 3 pins transistor package. Only have marqued in the
package the reference numbers: 004.
Num. reference: 004
Package type TO-92
3 pins
It is installed in one head light for controller the current for the led. He
alone with only one resistor of 1 Ohm generates and run at 500Khz controlling
the current and voltage. Also power up the voltage.
The condenser it is aditional component and does not internene in the operation
for generate
Images:
http://minus.com/mzK5bdrvN/2f
http://minus.com/mzK5bdrvN/1f

Any information for to find oany datashed or manufacturer will be welcomed

Regards



--- Posted via news://freenews.netfront.net/ - Complaints to news@netfront.net ---
 
On Fri, 20 Apr 2012 14:26:57 +0200, "Quim" <quim@t.es> put finger to
keyboard and composed:

Images:
http://minus.com/mzK5bdrvN/2f
http://minus.com/mzK5bdrvN/1f
Click to expand...
Can you supply a direct link to the images, without the popups,
banners, ads, etc?

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
 
http://i.minus.com/id7QxHlliDNLS.jpg
http://i.minus.com/iw5pvdBKmW3vg.jpg



Regards






"Franc Zabkar" <fzabkar@iinternode.on.net> escribió en el mensaje
news:3o99p7p365362l2tu3j3d88ccjg4f56spf@4ax.com...
On Fri, 20 Apr 2012 14:26:57 +0200, "Quim" <quim@t.es> put finger to
keyboard and composed:

Images:
http://minus.com/mzK5bdrvN/2f
http://minus.com/mzK5bdrvN/1f

Can you supply a direct link to the images, without the popups,
banners, ads, etc?

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
Click to expand...


--- Posted via news://freenews.netfront.net/ - Complaints to news@netfront.net ---
 
On Mon, 23 Apr 2012 12:13:49 +0200, "Quim" <quim@t.es> put finger to
keyboard and composed:

http://i.minus.com/id7QxHlliDNLS.jpg
http://i.minus.com/iw5pvdBKmW3vg.jpg
Click to expand...
The only switchmode device in a TO-92 package that I managed to find
was this one:
http://www.supertex.com/pdf/datasheets/HV9921.pdf

However, it doesn't look anything like yours. Its sense resistor is
internal to the package. Moreover, I would have expected a coil
somewhere in the circuit.

It may help us if you could draw a circuit diagram.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
 
Many thanks Franc
I seee that works directly at mains voltage this supertex driver, it is
interesting

The circuit :
http://i.minus.com/ibycpMXWjjRWVT.jpg
Not have any coil, I think that surely the cables themselves serve as inductance
at this frequence 500khz.


Regards




"Franc Zabkar" <fzabkar@iinternode.on.net> escribió en el mensaje
news:pbbbp7llqgus9stsd5l1pa5unve0t4pmbp@4ax.com...
On Mon, 23 Apr 2012 12:13:49 +0200, "Quim" <quim@t.es> put finger to
keyboard and composed:

http://i.minus.com/id7QxHlliDNLS.jpg
http://i.minus.com/iw5pvdBKmW3vg.jpg

The only switchmode device in a TO-92 package that I managed to find
was this one:
http://www.supertex.com/pdf/datasheets/HV9921.pdf

However, it doesn't look anything like yours. Its sense resistor is
internal to the package. Moreover, I would have expected a coil
somewhere in the circuit.

It may help us if you could draw a circuit diagram.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
Click to expand...


--- Posted via news://freenews.netfront.net/ - Complaints to news@netfront.net ---
 
On Tue, 24 Apr 2012 01:21:57 +0200, "Quim" <quim@t.es> put finger to
keyboard and composed:

The circuit :
http://i.minus.com/ibycpMXWjjRWVT.jpg

Not have any coil, I think that surely the cables themselves serve as inductance
at this frequence 500khz.
Click to expand...
If your circuit is correctly drawn, then I suspect that the component
that you have identified as a 1 ohm resistor may in fact be an
inductor.

According to the IC's output waveform, if the component were indeed a
1 ohm resistor, then it would be passing 3A current pulses. If the
duty cycle were 50%, then the power dissipation in the resistor would
be 4.5W. I don't believe any designer would be silly enough to waste
this much energy in a battery powered torch. Moreover, I doubt that a
TO-92 package would be robust enough for that kind of continuous
current rating.

Otherwise, if the component were indeed an inductor, then your circuit
would look like a boost converter, with the IC incorporating a PWM
controller and an N-channel MOSFET, possibly with current sensing as
well. In this case I suspect that your torch may be just as bright
using two 1.2V NiMH or NiCd cells, or maybe even a single cell.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
 
Yes, yo're right, I have disambled other time the head lamp, unsoldered this
resistor, and Ok, it is one inductor,
the tipical as one resistor 1/4W with the body a litle green. I measured it and
indicate 0,012mH,
really are brown, brown, black, 11uH.

Yes, the current and voltage is estabilized within certain limits. I see the
limit down are in the input 1,33v for to work well, and the output are 2,7vpp in
the waveform, and the led ligths.
Input Volts dc - output to the led, waveform voltage zero to peak
3 - 3,2
2,5 - 3,1
2 - 2,9
1,5 - 2,8
1,33 - 2,7
1 - waveform not square and I can't syncronize.


Regards




"Franc Zabkar" <fzabkar@iinternode.on.net> escribió en el mensaje
news:bqdep7tineh74b3ifja9bi31851a87fdl9@4ax.com...
On Tue, 24 Apr 2012 01:21:57 +0200, "Quim" <quim@t.es> put finger to
keyboard and composed:

The circuit :
http://i.minus.com/ibycpMXWjjRWVT.jpg

Not have any coil, I think that surely the cables themselves serve as
inductance
at this frequence 500khz.

If your circuit is correctly drawn, then I suspect that the component
that you have identified as a 1 ohm resistor may in fact be an
inductor.

According to the IC's output waveform, if the component were indeed a
1 ohm resistor, then it would be passing 3A current pulses. If the
duty cycle were 50%, then the power dissipation in the resistor would
be 4.5W. I don't believe any designer would be silly enough to waste
this much energy in a battery powered torch. Moreover, I doubt that a
TO-92 package would be robust enough for that kind of continuous
current rating.

Otherwise, if the component were indeed an inductor, then your circuit
would look like a boost converter, with the IC incorporating a PWM
controller and an N-channel MOSFET, possibly with current sensing as
well. In this case I suspect that your torch may be just as bright
using two 1.2V NiMH or NiCd cells, or maybe even a single cell.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
Click to expand...


--- Posted via news://freenews.netfront.net/ - Complaints to news@netfront.net ---
 
On Wed, 25 Apr 2012 17:35:27 +0200, "Quim" <quim@t.es> put finger to
keyboard and composed:

I have disambled other time the head lamp, unsoldered this
resistor, and Ok, it is one inductor,
the tipical as one resistor 1/4W with the body a litle green. I measured it and
indicate 0,012mH,
really are brown, brown, black, 11uH.

Yes, the current and voltage is estabilized within certain limits. I see the
limit down are in the input 1,33v for to work well, and the output are 2,7vpp in
the waveform, and the led ligths.
Input Volts dc - output to the led, waveform voltage zero to peak
3 - 3,2
2,5 - 3,1
2 - 2,9
1,5 - 2,8
1,33 - 2,7
1 - waveform not square and I can't syncronize.
Click to expand...
In retrospect we could have estimated the value of the inductor from
your first measurements.

Your 1W LED would have a rating of about 300mA at 3.2V.

The voltage across the inductor would be given by ...

V = L . dI/dt

So dI = V . dt / L

Assuming a 50% duty cycle at 500kHz, then dt = 1 usec.

So dI = 3 . 1E-6 / 11E-6 = 270mA

AISI, your "004" device probably has an internal current setting of
around 350mA. I still haven't managed to identify it, though. :-(

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
 
Very well the formulas and the calculatios.





"Franc Zabkar" <fzabkar@iinternode.on.net> escribió en el mensaje
news:6rqgp7pmn1ueno34h2bf2r2b4krokd5lcg@4ax.com...
On Wed, 25 Apr 2012 17:35:27 +0200, "Quim" <quim@t.es> put finger to
keyboard and composed:

I have disambled other time the head lamp, unsoldered this
resistor, and Ok, it is one inductor,
the tipical as one resistor 1/4W with the body a litle green. I measured it
and
indicate 0,012mH,
really are brown, brown, black, 11uH.

Yes, the current and voltage is estabilized within certain limits. I see the
limit down are in the input 1,33v for to work well, and the output are 2,7vpp
in
the waveform, and the led ligths.
Input Volts dc - output to the led, waveform voltage zero to peak
3 - 3,2
2,5 - 3,1
2 - 2,9
1,5 - 2,8
1,33 - 2,7
1 - waveform not square and I can't syncronize.

In retrospect we could have estimated the value of the inductor from
your first measurements.

Your 1W LED would have a rating of about 300mA at 3.2V.

The voltage across the inductor would be given by ...

V = L . dI/dt

So dI = V . dt / L

Assuming a 50% duty cycle at 500kHz, then dt = 1 usec.

So dI = 3 . 1E-6 / 11E-6 = 270mA

AISI, your "004" device probably has an internal current setting of
around 350mA. I still haven't managed to identify it, though. :-(

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
Click to expand...


--- Posted via news://freenews.netfront.net/ - Complaints to news@netfront.net ---
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top