I am working on a philips LCD tv with a broken psu. It was completely
dead and on opening it I found the usual story of bulging caps, signs
of overheating on the pcb thanks to the cramped vent-free design, etc
etc.
ZD 2 measures s/c, it is a P6KE16A, 16 volt 'transient voltage
suppresor' according to the datasheet he
http://www.datasheetcatalog.org/data...cs/mXuquwt.pdf

I'd like to know more about these components compared to a common-or-
garden zener. Apart from perhaps the faster protection action I'm not
clear on how they differ...
-B

"b" wrote in message
...
I am working on a philips LCD tv with a broken psu. It was completely
dead and on opening it I found the usual story of bulging caps, signs
of overheating on the pcb thanks to the cramped vent-free design, etc
etc.
ZD 2 measures s/c, it is a P6KE16A, 16 volt 'transient voltage
suppresor' according to the datasheet he
http://www.datasheetcatalog.org/data...cs/mXuquwt.pdf

I'd like to know more about these components compared to a common-or-
garden zener. Apart from perhaps the faster protection action I'm not
clear on how they differ...
-B


Do a search on Wikipedia for TVS diode, that should give you some
information.

Shaun

On Sat, 9 Jan 2010 17:51:48 -0600, "Shaun" put
finger to keyboard and composed:

"b" wrote in message
...
I am working on a philips LCD tv with a broken psu. It was completely
dead and on opening it I found the usual story of bulging caps, signs
of overheating on the pcb thanks to the cramped vent-free design, etc
etc.
ZD 2 measures s/c, it is a P6KE16A, 16 volt 'transient voltage
suppresor' according to the datasheet he
http://www.datasheetcatalog.org/data...cs/mXuquwt.pdf

I'd like to know more about these components compared to a common-or-
garden zener. Apart from perhaps the faster protection action I'm not
clear on how they differ...
-B


Do a search on Wikipedia for TVS diode, that should give you some
information.

Shaun

What is a Silicon Transient Voltage Suppressor and how does it work?
http://www.vishay.com/docs/88436/appnote.pdf

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

Franc Zabkar wrote in message
...
On Sat, 9 Jan 2010 17:51:48 -0600, "Shaun" put
finger to keyboard and composed:

"b" wrote in message
...
I am working on a philips LCD tv with a broken psu. It was completely
dead and on opening it I found the usual story of bulging caps, signs
of overheating on the pcb thanks to the cramped vent-free design, etc
etc.
ZD 2 measures s/c, it is a P6KE16A, 16 volt 'transient voltage
suppresor' according to the datasheet he

http://www.datasheetcatalog.org/data...ronics/mXuquwt
..pdf

I'd like to know more about these components compared to a common-or-
garden zener. Apart from perhaps the faster protection action I'm not
clear on how they differ...
-B


Do a search on Wikipedia for TVS diode, that should give you some
information.

Shaun

What is a Silicon Transient Voltage Suppressor and how does it work?
http://www.vishay.com/docs/88436/appnote.pdf

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

But,unlike zeners , are they guaranteed to go short circuit if they end up
in what becomes a sustained overvoltage rather than just a transient
situation ? or 2 different clases of VTS ?

On Mon, 11 Jan 2010 08:25:42 -0000, "N_Cook" put
finger to keyboard and composed:

But,unlike zeners , are they guaranteed to go short circuit if they end up
in what becomes a sustained overvoltage rather than just a transient
situation ? or 2 different clases of TVS ?

I watch various hard drive forums. HDs nowadays use TVS diodes on
their +5V and +12V rails. A sustained overvoltage from, say, a 19V
laptop adapter always (?) shorts the 12V diode, unless it is protected
by a fusible zero-ohm resistor.

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

Franc Zabkar wrote in message
...
On Mon, 11 Jan 2010 08:25:42 -0000, "N_Cook" put
finger to keyboard and composed:

But,unlike zeners , are they guaranteed to go short circuit if they end
up
in what becomes a sustained overvoltage rather than just a transient
situation ? or 2 different clases of TVS ?

I watch various hard drive forums. HDs nowadays use TVS diodes on
their +5V and +12V rails. A sustained overvoltage from, say, a 19V
laptop adapter always (?) shorts the 12V diode, unless it is protected
by a fusible zero-ohm resistor.

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

A zener would normally burn up/ go open circuit in overvoltage but do VTS
normally (but not guaranteed) go short thus providing crowbar protection if
fuse/fusible R/ current limiting/ps shut down, upstream. 80 percent/90
percent/ 99 percent of the time go s/c rather than o/c , any
guesses/knowlege?

Some interesting failure mode comparisons on this ap note
http://www.littelfuse.com/data/en/Ap...tes/an9768.pdf

Another question: what do the suffixes 'A' or 'CA' refer to? I ask
because I have been unable to find the exact replacement but have a
P6KE20CA. Not ideal, since the voltage rathing is 4v higher but I
assume it's better than nothing. Or would this be a bad idea due to
the different suffix?
cheers.
-B

b wrote:
what do the suffixes 'A' or 'CA' refer to?

http://google.com/search?q=transorb+...CA-denotes-*-*

JeffM wrote in message
...
b wrote:
what do the suffixes 'A' or 'CA' refer to?


http://google.com/search?q=transorb+...2+%22+suffix-C
A-denotes-*-*


But what is the function of
*-*
in the search string ?

b wrote:
what do the suffixes 'A' or 'CA' refer to?

JeffM wrote:
http://google.com/search?q=transorb+...CA-denotes-*-*

N_Cook wrote:
But what is the function of *-* in the search string ?

Wildcards. Google (alone, AFAIK) allows those.
When the results page appears, the words that appear in the phrase
where the asterisks are[1] will be highlighted
(along with the requested text).

....and, of course, the day after I post the link,
Google stops indexing the page. 8-(

Note also that when properly rendered on a schematic,
a CA device will have a nose-to-nose symbol reprentation.
..
..
[1] A hyphen is a valid word separator (as is a period).

so far I've been unable to find the part in question. As I need to
return this unit soon, I'm loath to leave it without some form of o/p
protection, is there anything strightforward I could add to this psu
to protect the appliance 'downstream'? possibly some form of crowbar
at least.
-B