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Is the SF-AW210 diode case neutral?

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Jun 12, 2010
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I know the diode thread shows the third pin as unused...

so would it be OK to build a laser that's case-positive?
I know I still have to supply the LD +/- from the driver but will it hurt anything if the hose (therefore the LD case) is in contact with the battery + ... I do not plan on connecting either terminal to the case pin.
 





I'm fairly certain that the diode is case neutral and that it is ok to connect the case pin
to either one of the two leads to make the diode case positive or negative. Doing this
shouldn't harm the diode
 
Yes, it's fine to do so - the only issue is when it's unconnected - apparently leaving it floating is a bad thing for ESD reasons.

Pet peeve, but this information would have been very easy to find by searching around rather than asking.
 
I don't think I can connect the neutral pin to the + pin. Just because the host is common to the battery + does not mean the LD case can be connected to the common + terminal. The LD must get its + supply directly and only from the driver. Because the flexdrive - supply is straight through (to the battery) connecting the LD + to the LD case pin in a + body host would be equivalent to connecting the LD directly to the battery terminals.

I suppose my question is, more precisely, if I leave the case pin floating on a + body host will there be any problems?
 
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flexdrive V5, SFAW210 diode.
The way my host comes together, the case must be positive.
 
flexdrive V5, SFAW210 diode.
The way my host comes together, the case must be positive.

Then the connections must be:

Casing to battery + end (via switch)
Casing to driver +v input
Driver -v to battery -v
Driver -v to diode -v
Driver +v output to diode +v

No connections to the case pin (presuming the case of diode connects to the host (casing) via metal-metal contact)!


I'm pretty sure that that's the correct way to wire it but I may be wrong. The other alternative is to isolate the diode module from the casing, but I believe the way I explained above works fine.

(This all depends somewhat whether or not the casing of the diode contacts the metal of the host, via the heatsink - I'm guessing by your description that it does and can't be isolated).
 
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Would there be any problems if my battery + connected directly to the Flexdrive + and the switch sits between the battery - and the flexdrive - ?
Said otherwise, my switch will interrupt the - power supply. Is this OK?

Thanks for the help so far guys?
 
A floating case is usually only advised to be shorted during extraction and installation isn't it? After it's installed you can safely connect it any way you wish without connecting the case pin? I understood that with any BR diodes, because of this floating case, you could choose which conductor path to put through the case. Case positive/negative, whichever. As the diode connections, assuming only one pin to one connection, are isolated anyway, it doesn't matter which way you do it. Check out the Flexdrive manual - http://hacylon.case.edu/ebay/laser_diode/MicroFlexDrive_V5_manual.pdf

As there are a number of ways to run your configuration.

M
:)
 


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