Wrong packaged diode

Hello all,

A board we produce has a battery that power a static RAM through a
diode. This is a SMD package, maybe a SMA, but can't say for sure
right now.

We have had a few problems with the battery circuit, that I know have
been solved changing the diode.

I have seen only one of those myself, and it looks like the diode is
packaged the other way round i.e. the package strip pointing to the
anode instead of pointing to the cathode.

Is this at all possible ? Am I doing something wrong ? Any similar
experiences around ?
As the board is produced in China, I would tend to think it is a
counterfeit diode.

Thank you in advance.

Josep

On Sun, 7 Feb 2010 03:17:45 -0800 (PST), djj08230 <djj08...@gmail.com
wrote:





Hello all,

A board we produce has a battery that power a static RAM through a
diode. This is a SMD package, maybe a SMA, but can't say for sure
right now.

We have had a few problems with the battery circuit, that I know have
been solved changing the diode.

I have seen only one of those myself, and it looks like the diode is
packaged the other way round i.e. the package strip pointing to the
anode instead of pointing to the cathode.

Is this at all possible ? Am I doing something wrong ? Any similar
experiences around ?
As the board is produced in China, I would tend to think it is a
counterfeit diode.

Thank you in advance.

Josep

More info needed. Many diodw packages can be obtained with alternate
pin-out or polarity, at a premium.

Some diodes have functional characteristics in the forward and reverse
direction, which might require their use in what looks like an
inverted mode.

RL- Hide quoted text -

- Show quoted text -

On Feb 7, 9:48 pm, legg <l...@nospam.magma.ca> wrote:
On Sun, 7 Feb 2010 03:17:45 -0800 (PST), djj08230 <djj08...@gmail.com
wrote:





Hello all,

A board we produce has a battery that power a static RAM through a
diode. This is a SMD package, maybe a SMA, but can't say for sure
right now.

We have had a few problems with the battery circuit, that I know have
been solved changing the diode.

I have seen only one of those myself, and it looks like the diode is
packaged the other way round i.e. the package strip pointing to the
anode instead of pointing to the cathode.

Is this at all possible ? Am I doing something wrong ? Any similar
experiences around ?
As the board is produced in China, I would tend to think it is a
counterfeit diode.

Thank you in advance.

Josep

More info needed. Many diodw packages can be obtained with alternate
pin-out or polarity, at a premium.

Some diodes have functional characteristics in the forward and reverse
direction, which might require their use in what looks like an
inverted mode.

RL- Hide quoted text -

- Show quoted text -

Thank you.
I've got the info now.(monday morning here)

The diode is MURS105T3G from On Semiconductors in an SMB package.
http://www.onsemi.com/pub_link/Collateral/MURS120T3-D.PDF

Probably not the best bit, but to me, this is an odd behaviour.
Testing the diode with a multimeter looks like the package is
reversed. Do they hand-assembly these tiny diodes ? (!!!)


Josep