On Mon, 26 Jan 2009 15:19:08 +0530, "pimpom"
put finger to keyboard and composed:

Arfa Daily wrote:
"pimpom" wrote in message
...
Does anyone have specific information about the protection
device at
the power supply inputs of hard disks?

I assume that it's a zener diode or something similar in
action such
as an IC that acts like a precision zener diode. It's not
difficult
to see how such a device would provide protection against
spikes,
over-voltage and reverse voltage by shorting the power rail to
ground and thereby triggering PSU shutdown.

Devices in the BUX C*** series seem to be widely used, but I
have
not been able to find a datasheet or other detailed info. Can
anybody shed some light on the matter?



BUX * devices are usually high voltage transistors

Yes. But transistors have the BUX followed by numeric characters.
These devices have a "C" before numerals.

The BU? marking code appears to be used by ST Microelectronics in
their SMBJ series 600W Transil (TVS) range.

See page 2 of the datasheet:
http://www.st.com/stonline/products/...re/ds/5616.pdf

The BUX marking isn't listed, but it would appear that the "U"
designates a unidirectional device.

The "C" appears to be the manufacturing location, followed by a
numeric YWW date code.

- Franc Zabkar
--
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