🚀 go-pugleaf

In article <gate.9uo2iB1w164w@toz.buffalo.ny.us> cyberman@toz.buffalo.ny.us (Cyberman) writes:
}DS>I just got a car audio amplifier from Coustic.  In the manual, it says it
}DS>uses hex-FET's and NOT to turn the amplifier on if there is no load on the
}DS>outputs.
}
}DS>I don't know anything about hex-FET's, but it seems unusual that an infinite
}DS>output impedance would cause damage to a transistor.  However, I'm always
}DS>learning just how much I don't know, so if someone could enlighten me in the
}DS>ways of hex-FET's or why this might cause damage, I'd be grateful.
}
}A hex fet is a high power MOSFET.  They work by having a metal
}oxide capacitor on the gate of it's internal fet.  Hex fets have
}a large surface and have thousand of fets in parallel.  anyhow.
}The reason they say this is it may build up a charge on the
}internal capacitors that exceed it's dielectric strength and
}internal voltage limits.  thus it would SELF destruct.

Really now, can you imagine a company of even minimal responsibility
putting an amplifer on the market that can be instantly destroyed if the
speaker leads open?  What would happen if the speaker was fused and the
fuse blew?  Would you expect the amplifier to go south at the same
time?  

If I designed a circuit of that level of stupidity, I'd want to do it
under an alias--and get out of the country immediately after submitting
my schematic. 

-- 

Norm Strong  (strong@tc.fluke.com)
2528 31st S.   Seattle WA 98144   USA