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Phil Allison[_2_] Phil Allison[_2_] is offline
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Default 250W amp - Mark Bass , Little Mark 250, of 2008, Italy


"Franc Zabkar"


If I use the following search parameters ...

http://www.google.com/search?q=vb+vs...filetype%3Apdf

... I get several promising leads, but all of them have the Vcc and
Ground pins interchanged.

http://www.datasheetcatalog.org/data...irf/ir2151.pdf
http://www.irf.com/product-info/data...ta/ir2153z.pdf
http://www.irf.com/product-info/data.../irs27951s.pdf
http://www.dianyuan.com/bbs/u/83/3675811258537068.pdf
http://bbs.dianyuan.com/bbs/u/70/2970761224726220.pdf



** The Italian schem may well contain a drawing error re pins 1 and cos
the IR2151 certainly looks the part.

Also, the amplifier output stage is NOT well protected from a short -
those 6.2 V zeners are not gonna save any of the IRFP mosfets, which BTW
need to be matched sets in order to share current.

PLUS, once the power amp fails short from rail to rail - the PSU has got
only one option.

It blows up.

Wot a dago piece of ****.



.... Phil