Cell Ph Charger Let the Smoke Out

  • Thread starter Watson A.Name - "Watt Sun
  • Start date
W

Watson A.Name - "Watt Sun

Guest
My cell phone cig lighter charger let the smoke out. The plastic
sleeve around the inductor was fried, so I pulled it out and it
measured 4.1 uH; whether that's correct or whether it has shorteed
turns, I don't know.

The Q1 high current PNP or P-Ch FET case split open, and it and the
inductor got so hot that it melted the solder and discolored the PC
board. But I don't think the traces are damaged. BTW, it's all thru
hole parts. :)

My main problem is that I can't read the part number on the Q1. It's
a TO-92 case, and looks like it would be a PNP Japanese type
transistor because the pinout is EBC (or the equivalent SDG in a FET).
I presumed this because the other two transistors are Japanese, as
marked below in the schematic. The unit is marked made in China. The
only things I can read on the face of the transistor case is an HE on
the upper right, and a C below that on the lower right.

I believe it failed bacause the lousily soldered wires were so very
close to shorting, but not touching the traces that it passed testing,
but then shorted and failed later. I got some pics, and I may post
them to ABSE. I looked at Sam's repair info here but couldn't find
anything about the SMPS or any transistors.
http://www.repairfaq.org/sam/aapsfaq.htm

The cig lighter plug case popped apart easily, so if you have one and
a minute, find out what the part number is and post it for us all. I
got to d/l and try out the Andy's schematic prog, and I entered the
schem, but I'm not sure about the value of the 100k 1%. It seems too
high, so I might be reading the bands backwards. Thanks.

View with courier Font


Cell Phone Charger by Watson A.Name Aug 30, 03
Down converts 12V auto cigarette lighter to the
cell phone battery voltage.

o------+--------+---------------------+ Q1 TO-92
+ IN | | | PNP HI CURR ??
| | Q2 2SA733 | or P-Ch FET ??
+------+ |< |< (totally fried)
| +-----| +-----------|
| | |\ | |\
| .-. | | | 4.1 uH
| 2K | | +-------+ | ___
| 1/8W| | | +------------+--------UUU-------+---o
| '-' .-. | 1N | | + OUT
.-. | | |1.8k | 5819 - +--------+---+ RED
| | | | |1/2W | Scho ^ | | |
| |3.3k | '-' --- ttky | | -. | +
'-' | | --- 470 == | 560 | | ###
| | === | pF Cer GND | ohm | | -+-
| LED | GND | | '-' | 100 uF
V --> +----------------+ | | | 16V
- --> | 560 100k 1/8W| +---+
| | ohm ___ 1% | ===
=== | +---|___|--+---|___|---+ GND
GND | | | +
| | ### 10 uF +----------+----o
\| | --- | | - OUT
Q3 2SA945 +--+-------+ | | 1.5 .-. BLK
<| | | === | ohm | |
| .-. 1k | GND | 1/2W| |
- IN === | | 1% | | '-'
o-+ GND | |1/8W | | |
| '-' +--------------------|<--+ ===
=== | Res = 1/4W unless GND
GND === otherwise noted 1N4148
GND

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de



--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
The simple and headache free solution for your cell phone charger is Trash
it, And step in your local 99 Cent store and grab a brand new cell ph Cig
lighter charger for 99 cents. You don't think that is much cheaper than
finding transistor by itself.!!!!????
Good luck and happy thrifty Shopping
Cyrus
"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bafd4998b537a3989696@news.dslextreme.com...
My cell phone cig lighter charger let the smoke out. The plastic
sleeve around the inductor was fried, so I pulled it out and it
measured 4.1 uH; whether that's correct or whether it has shorteed
turns, I don't know.

The Q1 high current PNP or P-Ch FET case split open, and it and the
inductor got so hot that it melted the solder and discolored the PC
board. But I don't think the traces are damaged. BTW, it's all thru
hole parts. :)

My main problem is that I can't read the part number on the Q1. It's
a TO-92 case, and looks like it would be a PNP Japanese type
transistor because the pinout is EBC (or the equivalent SDG in a FET).
I presumed this because the other two transistors are Japanese, as
marked below in the schematic. The unit is marked made in China. The
only things I can read on the face of the transistor case is an HE on
the upper right, and a C below that on the lower right.

I believe it failed bacause the lousily soldered wires were so very
close to shorting, but not touching the traces that it passed testing,
but then shorted and failed later. I got some pics, and I may post
them to ABSE. I looked at Sam's repair info here but couldn't find
anything about the SMPS or any transistors.
http://www.repairfaq.org/sam/aapsfaq.htm

The cig lighter plug case popped apart easily, so if you have one and
a minute, find out what the part number is and post it for us all. I
got to d/l and try out the Andy's schematic prog, and I entered the
schem, but I'm not sure about the value of the 100k 1%. It seems too
high, so I might be reading the bands backwards. Thanks.

View with courier Font


Cell Phone Charger by Watson A.Name Aug 30, 03
Down converts 12V auto cigarette lighter to the
cell phone battery voltage.

o------+--------+---------------------+ Q1 TO-92
+ IN | | | PNP HI CURR ??
| | Q2 2SA733 | or P-Ch FET ??
+------+ |< |< (totally fried)
| +-----| +-----------|
| | |\ | |\
| .-. | | | 4.1 uH
| 2K | | +-------+ | ___
| 1/8W| | | +------------+--------UUU-------+---o
| '-' .-. | 1N | | + OUT
.-. | | |1.8k | 5819 - +--------+---+ RED
| | | | |1/2W | Scho ^ | | |
| |3.3k | '-' --- ttky | | -. | +
'-' | | --- 470 == | 560 | | ###
| | === | pF Cer GND | ohm | | -+-
| LED | GND | | '-' | 100 uF
V --> +----------------+ | | | 16V
- --> | 560 100k 1/8W| +---+
| | ohm ___ 1% | ===
=== | +---|___|--+---|___|---+ GND
GND | | | +
| | ### 10 uF +----------+----o
\| | --- | | - OUT
Q3 2SA945 +--+-------+ | | 1.5 .-. BLK
| | | === | ohm | |
| .-. 1k | GND | 1/2W| |
- IN === | | 1% | | '-'
o-+ GND | |1/8W | | |
| '-' +--------------------|<--+ ===
=== | Res = 1/4W unless GND
GND === otherwise noted 1N4148
GND

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de



--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
Click to expand...
 
In article <chg4b.22210$S_.19390@fed1read01>, CyrusM@fox.net
mentioned...
The simple and headache free solution for your cell phone charger is Trash
it, And step in your local 99 Cent store and grab a brand new cell ph Cig
lighter charger for 99 cents. You don't think that is much cheaper than
finding transistor by itself.!!!!????
Good luck and happy thrifty Shopping
Cyrus
Click to expand...
You're probably right, except it's probably more like ten or twenty
dollars. I think more towards the latter.

I have a good stock of parts, if I could only find out what the part
is. So I could fix it for free. I may buy another one just to see
what they use. With my luck, it would be just a power resistor (to
limit the current) and zener (to limit the voltage), nothing more.

"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bafd4998b537a3989696@news.dslextreme.com...

My cell phone cig lighter charger let the smoke out. The plastic
sleeve around the inductor was fried, so I pulled it out and it
measured 4.1 uH; whether that's correct or whether it has shorteed
turns, I don't know.

The Q1 high current PNP or P-Ch FET case split open, and it and the
inductor got so hot that it melted the solder and discolored the PC
board. But I don't think the traces are damaged. BTW, it's all thru
hole parts. :)

My main problem is that I can't read the part number on the Q1. It's
a TO-92 case, and looks like it would be a PNP Japanese type
transistor because the pinout is EBC (or the equivalent SDG in a FET).
I presumed this because the other two transistors are Japanese, as
marked below in the schematic. The unit is marked made in China. The
only things I can read on the face of the transistor case is an HE on
the upper right, and a C below that on the lower right.

I believe it failed bacause the lousily soldered wires were so very
close to shorting, but not touching the traces that it passed testing,
but then shorted and failed later. I got some pics, and I may post
them to ABSE. I looked at Sam's repair info here but couldn't find
anything about the SMPS or any transistors.
http://www.repairfaq.org/sam/aapsfaq.htm

The cig lighter plug case popped apart easily, so if you have one and
a minute, find out what the part number is and post it for us all. I
got to d/l and try out the Andy's schematic prog, and I entered the
schem, but I'm not sure about the value of the 100k 1%. It seems too
high, so I might be reading the bands backwards. Thanks.

View with courier Font


Cell Phone Charger by Watson A.Name Aug 30, 03
Down converts 12V auto cigarette lighter to the
cell phone battery voltage.

o------+--------+---------------------+ Q1 TO-92
+ IN | | | PNP HI CURR ??
| | Q2 2SA733 | or P-Ch FET ??
+------+ |< |< (totally fried)
| +-----| +-----------|
| | |\ | |\
| .-. | | | 4.1 uH
| 2K | | +-------+ | ___
| 1/8W| | | +------------+--------UUU-------+---o
| '-' .-. | 1N | | + OUT
.-. | | |1.8k | 5819 - +--------+---+ RED
| | | | |1/2W | Scho ^ | | |
| |3.3k | '-' --- ttky | | -. | +
'-' | | --- 470 == | 560 | | ###
| | === | pF Cer GND | ohm | | -+-
| LED | GND | | '-' | 100 uF
V --> +----------------+ | | | 16V
- --> | 560 100k 1/8W| +---+
| | ohm ___ 1% | ===
=== | +---|___|--+---|___|---+ GND
GND | | | +
| | ### 10 uF +----------+----o
\| | --- | | - OUT
Q3 2SA945 +--+-------+ | | 1.5 .-. BLK
| | | === | ohm | |
| .-. 1k | GND | 1/2W| |
- IN === | | 1% | | '-'
o-+ GND | |1/8W | | |
| '-' +--------------------|<--+ ===
=== | Res = 1/4W unless GND
GND === otherwise noted 1N4148
GND

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

--
Click to expand...
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
Luckily I have the same charger that's used for Nokia cell phones. I
purchased 2 of them from 99 cent store one for Motorola starTAC and one for
my Nokia Cell phone. If you are insisting on fixing your charger here is the
Q1 part number PN2907A.

Good luck
Cyrus
"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bb61136c1682f99896a2@news.dslextreme.com...
In article <chg4b.22210$S_.19390@fed1read01>, CyrusM@fox.net
mentioned...
The simple and headache free solution for your cell phone charger is
Trash
it, And step in your local 99 Cent store and grab a brand new cell ph
Cig
lighter charger for 99 cents. You don't think that is much cheaper than
finding transistor by itself.!!!!????
Good luck and happy thrifty Shopping
Cyrus

You're probably right, except it's probably more like ten or twenty
dollars. I think more towards the latter.

I have a good stock of parts, if I could only find out what the part
is. So I could fix it for free. I may buy another one just to see
what they use. With my luck, it would be just a power resistor (to
limit the current) and zener (to limit the voltage), nothing more.

"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bafd4998b537a3989696@news.dslextreme.com...

My cell phone cig lighter charger let the smoke out. The plastic
sleeve around the inductor was fried, so I pulled it out and it
measured 4.1 uH; whether that's correct or whether it has shorteed
turns, I don't know.

The Q1 high current PNP or P-Ch FET case split open, and it and the
inductor got so hot that it melted the solder and discolored the PC
board. But I don't think the traces are damaged. BTW, it's all thru
hole parts. :)

My main problem is that I can't read the part number on the Q1. It's
a TO-92 case, and looks like it would be a PNP Japanese type
transistor because the pinout is EBC (or the equivalent SDG in a FET).
I presumed this because the other two transistors are Japanese, as
marked below in the schematic. The unit is marked made in China. The
only things I can read on the face of the transistor case is an HE on
the upper right, and a C below that on the lower right.

I believe it failed bacause the lousily soldered wires were so very
close to shorting, but not touching the traces that it passed testing,
but then shorted and failed later. I got some pics, and I may post
them to ABSE. I looked at Sam's repair info here but couldn't find
anything about the SMPS or any transistors.
http://www.repairfaq.org/sam/aapsfaq.htm

The cig lighter plug case popped apart easily, so if you have one and
a minute, find out what the part number is and post it for us all. I
got to d/l and try out the Andy's schematic prog, and I entered the
schem, but I'm not sure about the value of the 100k 1%. It seems too
high, so I might be reading the bands backwards. Thanks.

View with courier Font


Cell Phone Charger by Watson A.Name Aug 30, 03
Down converts 12V auto cigarette lighter to the
cell phone battery voltage.

o------+--------+---------------------+ Q1 TO-92
+ IN | | | PNP HI CURR ??
| | Q2 2SA733 | or P-Ch FET ??
+------+ |< |< (totally fried)
| +-----| +-----------|
| | |\ | |\
| .-. | | | 4.1 uH
| 2K | | +-------+ | ___
| 1/8W| | | +------------+--------UUU-------+---o
| '-' .-. | 1N | | + OUT
.-. | | |1.8k | 5819 - +--------+---+ RED
| | | | |1/2W | Scho ^ | | |
| |3.3k | '-' --- ttky | | -. | +
'-' | | --- 470 == | 560 | | ###
| | === | pF Cer GND | ohm | | -+-
| LED | GND | | '-' | 100 uF
V --> +----------------+ | | | 16V
- --> | 560 100k 1/8W| +---+
| | ohm ___ 1% | ===
=== | +---|___|--+---|___|---+ GND
GND | | | +
| | ### 10 uF +----------+----o
\| | --- | | - OUT
Q3 2SA945 +--+-------+ | | 1.5 .-. BLK
| | | === | ohm | |
| .-. 1k | GND | 1/2W| |
- IN === | | 1% | | '-'
o-+ GND | |1/8W | | |
| '-' +--------------------|<--+ ===
=== | Res = 1/4W unless GND
GND === otherwise noted 1N4148
GND

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

--

--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
Click to expand...
 
In article <JBp4b.22255$S_.13531@fed1read01>, CyrusM@fox.net
mentioned...
Luckily I have the same charger that's used for Nokia cell phones. I
purchased 2 of them from 99 cent store one for Motorola starTAC and one for
my Nokia Cell phone. If you are insisting on fixing your charger here is the
Q1 part number PN2907A.

Good luck
Cyrus
Click to expand...
Thank you for checking. But now the problem is how do I reconcile the
difference in pinout between the burned out transistor, which has a
standard Japanese pinout of E C B, with the pinout of a PN2907A,
which has a standard JEDEC pinout of E B C. Something's wrong here.


"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bb61136c1682f99896a2@news.dslextreme.com...
In article <chg4b.22210$S_.19390@fed1read01>, CyrusM@fox.net
mentioned...
The simple and headache free solution for your cell phone charger is
Trash
it, And step in your local 99 Cent store and grab a brand new cell ph
Cig
lighter charger for 99 cents. You don't think that is much cheaper than
finding transistor by itself.!!!!????
Good luck and happy thrifty Shopping
Cyrus

You're probably right, except it's probably more like ten or twenty
dollars. I think more towards the latter.

I have a good stock of parts, if I could only find out what the part
is. So I could fix it for free. I may buy another one just to see
what they use. With my luck, it would be just a power resistor (to
limit the current) and zener (to limit the voltage), nothing more.

"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bafd4998b537a3989696@news.dslextreme.com...

My cell phone cig lighter charger let the smoke out. The plastic
sleeve around the inductor was fried, so I pulled it out and it
measured 4.1 uH; whether that's correct or whether it has shorteed
turns, I don't know.

The Q1 high current PNP or P-Ch FET case split open, and it and the
inductor got so hot that it melted the solder and discolored the PC
board. But I don't think the traces are damaged. BTW, it's all thru
hole parts. :)

My main problem is that I can't read the part number on the Q1. It's
a TO-92 case, and looks like it would be a PNP Japanese type
transistor because the pinout is EBC (or the equivalent SDG in a FET).
I presumed this because the other two transistors are Japanese, as
marked below in the schematic. The unit is marked made in China. The
only things I can read on the face of the transistor case is an HE on
the upper right, and a C below that on the lower right.

I believe it failed bacause the lousily soldered wires were so very
close to shorting, but not touching the traces that it passed testing,
but then shorted and failed later. I got some pics, and I may post
them to ABSE. I looked at Sam's repair info here but couldn't find
anything about the SMPS or any transistors.
http://www.repairfaq.org/sam/aapsfaq.htm

The cig lighter plug case popped apart easily, so if you have one and
a minute, find out what the part number is and post it for us all. I
got to d/l and try out the Andy's schematic prog, and I entered the
schem, but I'm not sure about the value of the 100k 1%. It seems too
high, so I might be reading the bands backwards. Thanks.

View with courier Font


Cell Phone Charger by Watson A.Name Aug 30, 03
Down converts 12V auto cigarette lighter to the
cell phone battery voltage.

o------+--------+---------------------+ Q1 TO-92
+ IN | | | PNP HI CURR ??
| | Q2 2SA733 | or P-Ch FET ??
+------+ |< |< (totally fried)
| +-----| +-----------|
| | |\ | |\ (heat damaged)
| .-. | | | 4.1 uH ??
| 2K | | +-------+ | ___
| 1/8W| | | +------------+--------UUU-------+---o
| '-' .-. | 1N | | + OUT
.-. | | |1.8k | 5819 - +--------+---+ RED
| | | | |1/2W | Scho ^ | | |
| |3.3k | '-' --- ttky | | -. | +
'-' | | --- 470 == | 560 | | ###
| | === | pF Cer GND | ohm | | -+-
| LED | GND | | '-' | 100 uF
V --> +----------------+ | | | 16V
- --> | 560 ohm 100k? 1/8W| +---+
| | ___ ___ 1% | ===
=== | +---|___|--+---|___|---+ GND
GND | | | +
| | ### 10 uF +----------+----o
\| | --- | | - OUT
Q3 2SA945 +--+-------+ | | 1.5 .-. BLK
| | | === | ohm | |
| .-. 1k | GND | 1/2W| |
- IN === | | 1% | | '-'
o-+ GND | |1/8W | | |
| '-' +--------------------|<--+ ===
=== | Res = 1/4W unless GND
GND === otherwise noted 1N4148
GND

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

--

--
Click to expand...

--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
Use KSB722 or 2SB1217
I have two very similar crappy cigarette lighter plugs, and that's
what's inside. The inrush current is high on these because the pass
transistor has to be hard on untill the correct output voltage is
reached. This means the inductor core may saturate untill the output
filter cap charges; ouch!

On Sat, 30 Aug 2003 19:29:05 -0700, Watson A.Name - "Watt Sun"
<alondra101@hotmail.com> wrote:

o------+--------+---------------------+ Q1 TO-92
+ IN | | | PNP HI CURR ??
| | Q2 2SA733 | or P-Ch FET ??
+------+ |< |< (totally fried)
| +-----| +-----------|
| | |\ | |\
| .-. | | | 4.1 uH
| 2K | | +-------+ | ___
| 1/8W| | | +------------+--------UUU-------+---o
| '-' .-. | 1N | | + OUT
.-. | | |1.8k | 5819 - +--------+---+ RED
| | | | |1/2W | Scho ^ | | |
| |3.3k | '-' --- ttky | | -. | +
'-' | | --- 470 == | 560 | | ###
| | === | pF Cer GND | ohm | | -+-
| LED | GND | | '-' | 100 uF
V --> +----------------+ | | | 16V
- --> | 560 100k 1/8W| +---+
| | ohm ___ 1% | ===
=== | +---|___|--+---|___|---+ GND
GND | | | +
| | ### 10 uF +----------+----o
\| | --- | | - OUT
Q3 2SA945 +--+-------+ | | 1.5 .-. BLK
| | | === | ohm | |
| .-. 1k | GND | 1/2W| |
- IN === | | 1% | | '-'
o-+ GND | |1/8W | | |
| '-' +--------------------|<--+ ===
=== | Res = 1/4W unless GND
GND === otherwise noted 1N4148
GND
Click to expand...
 
"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bc28f066dbab5a9896aa@news.dslextreme.com...
In article <JBp4b.22255$S_.13531@fed1read01>, CyrusM@fox.net
mentioned...
Luckily I have the same charger that's used for Nokia cell phones. I
purchased 2 of them from 99 cent store one for Motorola starTAC and one
for
my Nokia Cell phone. If you are insisting on fixing your charger here is
the
Q1 part number PN2907A.

Good luck
Cyrus

Thank you for checking. But now the problem is how do I reconcile the
difference in pinout between the burned out transistor, which has a
standard Japanese pinout of E C B, with the pinout of a PN2907A,
which has a standard JEDEC pinout of E B C. Something's wrong here.
Click to expand...
I really don't understand why you want to repair this throwaway item. I like
playing around with lost causes myself, but a cellphone car charger? Even
here in 'rip-off Britain' they are only about 3 or 4 quid (that's 4-6
bucks;-))

Dave
 
Look this web site for PN2907A Data , and if you look close with magnifying
lens you will find out Q1 is not inside silk screen, it is shifted. I have
the same charger in my hand . Board no, HH-05A BCC
http://www.fairchildsemi.com/ds/PN/PN2907A.pdf

Nothing is wrong, trust me
Cyrus

"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bc28f066dbab5a9896aa@news.dslextreme.com...
In article <JBp4b.22255$S_.13531@fed1read01>, CyrusM@fox.net
mentioned...
Luckily I have the same charger that's used for Nokia cell phones. I
purchased 2 of them from 99 cent store one for Motorola starTAC and one
for
my Nokia Cell phone. If you are insisting on fixing your charger here is
the
Q1 part number PN2907A.

Good luck
Cyrus

Thank you for checking. But now the problem is how do I reconcile the
difference in pinout between the burned out transistor, which has a
standard Japanese pinout of E C B, with the pinout of a PN2907A,
which has a standard JEDEC pinout of E B C. Something's wrong here.


"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bb61136c1682f99896a2@news.dslextreme.com...
In article <chg4b.22210$S_.19390@fed1read01>, CyrusM@fox.net
mentioned...
The simple and headache free solution for your cell phone charger is
Trash
it, And step in your local 99 Cent store and grab a brand new cell
ph
Cig
lighter charger for 99 cents. You don't think that is much cheaper
than
finding transistor by itself.!!!!????
Good luck and happy thrifty Shopping
Cyrus

You're probably right, except it's probably more like ten or twenty
dollars. I think more towards the latter.

I have a good stock of parts, if I could only find out what the part
is. So I could fix it for free. I may buy another one just to see
what they use. With my luck, it would be just a power resistor (to
limit the current) and zener (to limit the voltage), nothing more.

"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bafd4998b537a3989696@news.dslextreme.com...

My cell phone cig lighter charger let the smoke out. The plastic
sleeve around the inductor was fried, so I pulled it out and it
measured 4.1 uH; whether that's correct or whether it has shorteed
turns, I don't know.

The Q1 high current PNP or P-Ch FET case split open, and it and
the
inductor got so hot that it melted the solder and discolored the
PC
board. But I don't think the traces are damaged. BTW, it's all
thru
hole parts. :)

My main problem is that I can't read the part number on the Q1.
It's
a TO-92 case, and looks like it would be a PNP Japanese type
transistor because the pinout is EBC (or the equivalent SDG in a
FET).
I presumed this because the other two transistors are Japanese, as
marked below in the schematic. The unit is marked made in China.
The
only things I can read on the face of the transistor case is an HE
on
the upper right, and a C below that on the lower right.

I believe it failed bacause the lousily soldered wires were so
very
close to shorting, but not touching the traces that it passed
testing,
but then shorted and failed later. I got some pics, and I may
post
them to ABSE. I looked at Sam's repair info here but couldn't
find
anything about the SMPS or any transistors.
http://www.repairfaq.org/sam/aapsfaq.htm

The cig lighter plug case popped apart easily, so if you have one
and
a minute, find out what the part number is and post it for us all.
I
got to d/l and try out the Andy's schematic prog, and I entered
the
schem, but I'm not sure about the value of the 100k 1%. It seems
too
high, so I might be reading the bands backwards. Thanks.

View with courier Font


Cell Phone Charger by Watson A.Name Aug 30, 03
Down converts 12V auto cigarette lighter to the
cell phone battery voltage.

o------+--------+---------------------+ Q1 TO-92
+ IN | | | PNP HI CURR ??
| | Q2 2SA733 | or P-Ch FET ??
+------+ |< |< (totally fried)
| +-----| +-----------|
| | |\ | |\ (heat damaged)
| .-. | | | 4.1 uH ??
| 2K | | +-------+ | ___
| 1/8W| | | +------------+--------UUU-------+---o
| '-' .-. | 1N | | +
OUT
.-. | | |1.8k | 5819 - +--------+---+
RED
| | | | |1/2W | Scho ^ | | |
| |3.3k | '-' --- ttky | | -. | +
'-' | | --- 470 == | 560 | | ###
| | === | pF Cer GND | ohm | | -+-
| LED | GND | | '-' | 100
uF
V --> +----------------+ | | |
16V
- --> | 560 ohm 100k? 1/8W| +---+
| | ___ ___ 1% | ===
=== | +---|___|--+---|___|---+ GND
GND | | | +
| | ### 10 uF
+----------+----o
\| | --- | | -
OUT
Q3 2SA945 +--+-------+ | | 1.5 .-.
BLK
| | | === | ohm | |
| .-. 1k | GND | 1/2W| |
- IN === | | 1% | | '-'
o-+ GND | |1/8W | | |
| '-' +--------------------|<--+ ===
=== | Res = 1/4W unless GND
GND === otherwise noted 1N4148
GND

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

--

--


--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
Click to expand...
 
In article <nCC4b.22482$S_.14779@fed1read01>, CyrusM@fox.net
mentioned...
Look this web site for PN2907A Data , and if you look close with magnifying
lens you will find out Q1 is not inside silk screen, it is shifted. I have
the same charger in my hand . Board no, HH-05A BCC
http://www.fairchildsemi.com/ds/PN/PN2907A.pdf

Nothing is wrong, trust me
Cyrus
Click to expand...
I tried a couple times to d/l the Fairchild data sheet, but it just
gave me an hourglass for ten minutes, so I went to the Philips website
and downloaded their .pdf of PN2907A. As I mentioned, the pinout is E
B C, and the transistor that fried has a pinout of E C B. The board
says HH-S01DS and 20 SEP 02 on it. I don't think you have the same PC
board as mine. Thanks.

"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bc28f066dbab5a9896aa@news.dslextreme.com...
In article <JBp4b.22255$S_.13531@fed1read01>, CyrusM@fox.net
mentioned...
Luckily I have the same charger that's used for Nokia cell phones. I
purchased 2 of them from 99 cent store one for Motorola starTAC and one
for
my Nokia Cell phone. If you are insisting on fixing your charger here is
the
Q1 part number PN2907A.

Good luck
Cyrus

Thank you for checking. But now the problem is how do I reconcile the
difference in pinout between the burned out transistor, which has a
standard Japanese pinout of E C B, with the pinout of a PN2907A,
which has a standard JEDEC pinout of E B C. Something's wrong here.
Click to expand...
[snip]
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
You better get a new one. You will end up spending a lot of time on it,
and near the cost of replacing it. Then if you fix it, and it is not
correct because of something else you missed, you stand the chance of
damaging the phone. Now this will be expensive!

--

Greetings,

Jerry Greenberg GLG Technologies GLG
==============================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
Instruments http://www.zoom-one.com/glgtech.htm
==============================================
"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bafd4998b537a3989696@news.dslextreme.com...

My cell phone cig lighter charger let the smoke out. The plastic
sleeve around the inductor was fried, so I pulled it out and it
measured 4.1 uH; whether that's correct or whether it has shorteed
turns, I don't know.

The Q1 high current PNP or P-Ch FET case split open, and it and the
inductor got so hot that it melted the solder and discolored the PC
board. But I don't think the traces are damaged. BTW, it's all thru
hole parts. :)

My main problem is that I can't read the part number on the Q1. It's
a TO-92 case, and looks like it would be a PNP Japanese type
transistor because the pinout is EBC (or the equivalent SDG in a FET).
I presumed this because the other two transistors are Japanese, as
marked below in the schematic. The unit is marked made in China. The
only things I can read on the face of the transistor case is an HE on
the upper right, and a C below that on the lower right.

I believe it failed bacause the lousily soldered wires were so very
close to shorting, but not touching the traces that it passed testing,
but then shorted and failed later. I got some pics, and I may post
them to ABSE. I looked at Sam's repair info here but couldn't find
anything about the SMPS or any transistors.
http://www.repairfaq.org/sam/aapsfaq.htm

The cig lighter plug case popped apart easily, so if you have one and
a minute, find out what the part number is and post it for us all. I
got to d/l and try out the Andy's schematic prog, and I entered the
schem, but I'm not sure about the value of the 100k 1%. It seems too
high, so I might be reading the bands backwards. Thanks.

View with courier Font


Cell Phone Charger by Watson A.Name Aug 30, 03
Down converts 12V auto cigarette lighter to the
cell phone battery voltage.

o------+--------+---------------------+ Q1 TO-92
+ IN | | | PNP HI CURR ??
| | Q2 2SA733 | or P-Ch FET ??
+------+ |< |< (totally fried)
| +-----| +-----------|
| | |\ | |\
| .-. | | | 4.1 uH
| 2K | | +-------+ | ___
| 1/8W| | | +------------+--------UUU-------+---o
| '-' .-. | 1N | | + OUT
.-. | | |1.8k | 5819 - +--------+---+ RED
| | | | |1/2W | Scho ^ | | |
| |3.3k | '-' --- ttky | | -. | +
'-' | | --- 470 == | 560 | | ###
| | === | pF Cer GND | ohm | | -+-
| LED | GND | | '-' | 100 uF
V --> +----------------+ | | | 16V
- --> | 560 100k 1/8W| +---+
| | ohm ___ 1% | ===
=== | +---|___|--+---|___|---+ GND
GND | | | +
| | ### 10 uF +----------+----o
\| | --- | | - OUT
Q3 2SA945 +--+-------+ | | 1.5 .-. BLK
<| | | === | ohm | |
| .-. 1k | GND | 1/2W| |
- IN === | | 1% | | '-'
o-+ GND | |1/8W | | |
| '-' +--------------------|<--+ ===
=== | Res = 1/4W unless GND
GND === otherwise noted 1N4148
GND

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de



--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
With out " Adobe Acrobat 5.0 " or 4.0 software at your Computer ,it is
impossible to open that screen. It shows B is in the center of PN2907A. It
is strange, these are few parts that I can see on the board.
Q1= PN2907A Q2= A733 Q3= C945 C1=471 C2=10uF C3= 100uF
L1= Coil
R6= 3.3 Ohm 1/2W R4=560 OHM R5= 1K %1 1.8k 1/2w 3.3K
1N 5 XXXX Diode 2KOkm
LED 100kOhm 1% it seems 1N4148 diode total of 18 patrs . With PCB
19 Parts.

Cyrus
"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bce2669ecb7a099896b6@news.dslextreme.com...
In article <nCC4b.22482$S_.14779@fed1read01>, CyrusM@fox.net
mentioned...
Look this web site for PN2907A Data , and if you look close with
magnifying
lens you will find out Q1 is not inside silk screen, it is shifted. I
have
the same charger in my hand . Board no, HH-05A BCC
http://www.fairchildsemi.com/ds/PN/PN2907A.pdf

Nothing is wrong, trust me
Cyrus

I tried a couple times to d/l the Fairchild data sheet, but it just
gave me an hourglass for ten minutes, so I went to the Philips website
and downloaded their .pdf of PN2907A. As I mentioned, the pinout is E
B C, and the transistor that fried has a pinout of E C B. The board
says HH-S01DS and 20 SEP 02 on it. I don't think you have the same PC
board as mine. Thanks.

"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bc28f066dbab5a9896aa@news.dslextreme.com...
In article <JBp4b.22255$S_.13531@fed1read01>, CyrusM@fox.net
mentioned...
Luckily I have the same charger that's used for Nokia cell phones.
I
purchased 2 of them from 99 cent store one for Motorola starTAC and
one
for
my Nokia Cell phone. If you are insisting on fixing your charger
here is
the
Q1 part number PN2907A.

Good luck
Cyrus

Thank you for checking. But now the problem is how do I reconcile the
difference in pinout between the burned out transistor, which has a
standard Japanese pinout of E C B, with the pinout of a PN2907A,
which has a standard JEDEC pinout of E B C. Something's wrong here.

[snip]
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
Click to expand...
 
In article <8gn5lv0nfkph3a30up1p2rtcn3kuso5gh9@4ax.com>,
snovotill@hotmail.com mentioned...
Use KSB722 or 2SB1217
I have two very similar crappy cigarette lighter plugs, and that's
what's inside. The inrush current is high on these because the pass
transistor has to be hard on untill the correct output voltage is
reached. This means the inductor core may saturate untill the output
filter cap charges; ouch!
Click to expand...
I found the data sheet for the 2SB1217 on the NEC website, and it
looks like it's a TO-126 case. I tried a transistor in that case that
I had in the junk box and it might fit if I file down the stoppers on
the leads. It looks like a good choice, spec wise. The KSB722 didn't
come up with anything in Google so I went to both Fairchild and
www.KEC.co.kr websites, but came up with nothing. So I tried
www.NTEinc.com and it came back with no match. Thanks.


On Sat, 30 Aug 2003 19:29:05 -0700, Watson A.Name - "Watt Sun"
alondra101@hotmail.com> wrote:

o------+--------+---------------------+ Q1 TO-92
+ IN | | | PNP HI CURR ??
| | Q2 2SA733 | or P-Ch FET ??
+------+ |< |< (totally fried)
| +-----| +-----------|
| | |\ | |\
| .-. | | | 4.1 uH
| 2K | | +-------+ | ___
| 1/8W| | | +------------+--------UUU-------+---o
| '-' .-. | 1N | | + OUT
.-. | | |1.8k | 5819 - +--------+---+ RED
| | | | |1/2W | Scho ^ | | |
| |3.3k | '-' --- ttky | | -. | +
'-' | | --- 470 == | 560 | | ###
| | === | pF Cer GND | ohm | | -+-
| LED | GND | | '-' | 100 uF
V --> +----------------+ | | | 16V
- --> | 560 100k 1/8W| +---+
| | ohm ___ 1% | ===
=== | +---|___|--+---|___|---+ GND
GND | | | +
| | ### 10 uF +----------+----o
\| | --- | | - OUT
Q3 2SA945 +--+-------+ | | 1.5 .-. BLK
| | | === | ohm | |
| .-. 1k | GND | 1/2W| |
- IN === | | 1% | | '-'
o-+ GND | |1/8W | | |
| '-' +--------------------|<--+ ===
=== | Res = 1/4W unless GND
GND === otherwise noted 1N4148
GND
Click to expand...
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
In article <2gI4b.22831$S_.21369@fed1read01>, CyrusM@fox.net
mentioned...
With out " Adobe Acrobat 5.0 " or 4.0 software at your Computer ,it is
impossible to open that screen. It shows B is in the center of PN2907A. It
Click to expand...
Yeah, I had no problem d/l'ing the .PDF of the Philips PN2907A (I have
acrobat reader 5.0). I had problems with reading the 1%ers, because
they have the bands evenly spaced so it's difficult to tell which end
goes on the left. I also got 100k, 1%, but that seems too high.
Thanks for the additional info. I'm gonna look for another
replacement at the Rat Shack store, but my guess is that it'll cost
over ten dollars. Maybe I should check Wal-mart or Target..

is strange, these are few parts that I can see on the board.
Q1= PN2907A Q2= A733 Q3= C945 C1=471 C2=10uF C3= 100uF
L1= Coil
R6= 3.3 Ohm 1/2W R4=560 OHM R5= 1K %1 1.8k 1/2w 3.3K
1N 5 XXXX Diode 2KOkm
LED 100kOhm 1% it seems 1N4148 diode total of 18 patrs . With PCB
19 Parts.

Cyrus
"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bce2669ecb7a099896b6@news.dslextreme.com...
In article <nCC4b.22482$S_.14779@fed1read01>, CyrusM@fox.net
mentioned...
Look this web site for PN2907A Data , and if you look close with
magnifying
lens you will find out Q1 is not inside silk screen, it is shifted. I
have
the same charger in my hand . Board no, HH-05A BCC
http://www.fairchildsemi.com/ds/PN/PN2907A.pdf

Nothing is wrong, trust me
Cyrus

I tried a couple times to d/l the Fairchild data sheet, but it just
gave me an hourglass for ten minutes, so I went to the Philips website
and downloaded their .pdf of PN2907A. As I mentioned, the pinout is E
B C, and the transistor that fried has a pinout of E C B. The board
says HH-S01DS and 20 SEP 02 on it. I don't think you have the same PC
board as mine. Thanks.

"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bc28f066dbab5a9896aa@news.dslextreme.com...
In article <JBp4b.22255$S_.13531@fed1read01>, CyrusM@fox.net
mentioned...
Luckily I have the same charger that's used for Nokia cell phones.
I
purchased 2 of them from 99 cent store one for Motorola starTAC and
one
for
my Nokia Cell phone. If you are insisting on fixing your charger
here is
the
Q1 part number PN2907A.

Good luck
Cyrus

Thank you for checking. But now the problem is how do I reconcile the
difference in pinout between the burned out transistor, which has a
standard Japanese pinout of E C B, with the pinout of a PN2907A,
which has a standard JEDEC pinout of E B C. Something's wrong here.

[snip]
--
Click to expand...
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
In article <bivhk1$43i$1@news.eusc.inter.net>, jerryg@total.net
mentioned...
You better get a new one. You will end up spending a lot of time on it,
and near the cost of replacing it. Then if you fix it, and it is not
correct because of something else you missed, you stand the chance of
damaging the phone. Now this will be expensive!
Click to expand...
Yeah, I thought about that, too. When it fried, it blew out the 2 Amp
fuse in the nose of the cig lighter plug. I'm wondering if it didn't
damage the charging circuit in the phone. The phone is working okay,
but I haven't charged it since it went bad. I'll have to check.


--

Greetings,

Jerry Greenberg GLG Technologies GLG
==============================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
Instruments http://www.zoom-one.com/glgtech.htm
==============================================
"Watson A.Name - Watt Sun" <alondra101@hotmail.com> wrote in message
news:MPG.19bafd4998b537a3989696@news.dslextreme.com...

My cell phone cig lighter charger let the smoke out. The plastic
sleeve around the inductor was fried, so I pulled it out and it
measured 4.1 uH; whether that's correct or whether it has shorteed
turns, I don't know.

The Q1 high current PNP or P-Ch FET case split open, and it and the
inductor got so hot that it melted the solder and discolored the PC
board. But I don't think the traces are damaged. BTW, it's all thru
hole parts. :)

My main problem is that I can't read the part number on the Q1. It's
a TO-92 case, and looks like it would be a PNP Japanese type
transistor because the pinout is EBC (or the equivalent SDG in a FET).
I presumed this because the other two transistors are Japanese, as
marked below in the schematic. The unit is marked made in China. The
only things I can read on the face of the transistor case is an HE on
the upper right, and a C below that on the lower right.

I believe it failed bacause the lousily soldered wires were so very
close to shorting, but not touching the traces that it passed testing,
but then shorted and failed later. I got some pics, and I may post
them to ABSE. I looked at Sam's repair info here but couldn't find
anything about the SMPS or any transistors.
http://www.repairfaq.org/sam/aapsfaq.htm

The cig lighter plug case popped apart easily, so if you have one and
a minute, find out what the part number is and post it for us all. I
got to d/l and try out the Andy's schematic prog, and I entered the
schem, but I'm not sure about the value of the 100k 1%. It seems too
high, so I might be reading the bands backwards. Thanks.

View with courier Font


Cell Phone Charger by Watson A.Name Aug 30, 03
Down converts 12V auto cigarette lighter to the
cell phone battery voltage.

o------+--------+---------------------+ Q1 TO-92
+ IN | | | PNP HI CURR ??
| | Q2 2SA733 | or P-Ch FET ??
+------+ |< |< (totally fried)
| +-----| +-----------|
| | |\ | |\
| .-. | | | 4.1 uH
| 2K | | +-------+ | ___
| 1/8W| | | +------------+--------UUU-------+---o
| '-' .-. | 1N | | + OUT
.-. | | |1.8k | 5819 - +--------+---+ RED
| | | | |1/2W | Scho ^ | | |
| |3.3k | '-' --- ttky | | -. | +
'-' | | --- 470 == | 560 | | ###
| | === | pF Cer GND | ohm | | -+-
| LED | GND | | '-' | 100 uF
V --> +----------------+ | | | 16V
- --> | 560 100k 1/8W| +---+
| | ohm ___ 1% | ===
=== | +---|___|--+---|___|---+ GND
GND | | | +
| | ### 10 uF +----------+----o
\| | --- | | - OUT
Q3 2SA945 +--+-------+ | | 1.5 .-. BLK
| | | === | ohm | |
| .-. 1k | GND | 1/2W| |
- IN === | | 1% | | '-'
o-+ GND | |1/8W | | |
| '-' +--------------------|<--+ ===
=== | Res = 1/4W unless GND
GND === otherwise noted 1N4148
GND

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de
Click to expand...
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
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