3 lead smd component designated as CR5?

[drsmith]

I have an lcd inverter board with two components I'm trying to
identify. Each looks like a standard transistor with 3 leads(2 on one
side and a third in the middle of the opposite side). The
designations are cr5 and cr10. Each package has a C3 marked on it in a
somewhat odd font.

While I realize that the general CR label is applied to diodes, I've
never seen a diode with 3 leads. Other diodes on the same board bear
the CR designation.

Any ideas what these are?

Thanks.

--drsmith

 

[Walter Harley]

"drsmith" <drsmithhm@hotmail.com> wrote in message
news:c7c208d1.0404031559.baa52e6@posting.google.com...

While I realize that the general CR label is applied to diodes, I've
never seen a diode with 3 leads. Other diodes on the same board bear
the CR designation.

Surface mount diodes often come in 3-lead packages, presumably because
they're easier to mount (for instance, easier to get the polarity right).
Sometimes you get two diodes in the package; sometimes one lead is not
connected internally.

http://www.tkb-4u.com/code/smdcode/smdcodeC.php says that C3 is used, among
other things, for an HP dual schottky rectifier. YMMV.

 

[drsmith]

"Walter Harley" <walterh@cafewalterNOSPAM.com> wrote in message news:<c4oiod$fk7$0@216.39.172.65>...

"drsmith" <drsmithhm@hotmail.com> wrote in message
news:c7c208d1.0404031559.baa52e6@posting.google.com...
While I realize that the general CR label is applied to diodes, I've
never seen a diode with 3 leads. Other diodes on the same board bear
the CR designation.

Surface mount diodes often come in 3-lead packages, presumably because
they're easier to mount (for instance, easier to get the polarity right).
Sometimes you get two diodes in the package; sometimes one lead is not
connected internally.

http://www.tkb-4u.com/code/smdcode/smdcodeC.php says that C3 is used, among
other things, for an HP dual schottky rectifier. YMMV.

Thanks. I did find the page you mentioned, but it seemed like you had to
know what type of component/package you had before you could get a
reference to an actual part number. You may be right that it's a dual
schottky rectifier. I'll research it further.

Otherwise, I prepared a page so you could actually see what I'm talking
about: http://www.grimoire7.com/computing/inverter.html

Thanks again.
--drsmith

 

[Walter Harley]

"drsmith" <drsmithhm@hotmail.com> wrote in message
news:c7c208d1.0404040744.23ad7569@posting.google.com...

Thanks. I did find the page you mentioned, but it seemed like you had to
know what type of component/package you had before you could get a
reference to an actual part number. You may be right that it's a dual
schottky rectifier. I'll research it further.

Yes, that's right. The marking numbers for SMD devices are not unique.
Different manufacturers use the same codes for different devices. Sad but
true. (Probably inevitable, if you consider the number of different devices
and compare it to the number of short codes.) And as far as I've been able
to determine there is no single repository that contains all the codes.

Otherwise, I prepared a page so you could actually see what I'm talking
about: http://www.grimoire7.com/computing/inverter.html

It looks like all three terminals are connected to separate traces; you
could confirm with an ohmmeter. If so, a dual diode is a good guess. The
package looks like SOT-23.

I usually end up trying to trace enough of the schematic to figure out the
function of the device.