Combining functionality can make sense under certain circumstances.
If, for example, the cost of producing the seperate parts drops to the
point where you can save money by making one combined part and
exconomicaly toss it if it fails.
I used to be against computer motherboards that included all of the common
interfaces (FDD, HDD, Serial, etc.)
But now, the integrated motherboards are so cheap, it doesn't matter if
one part fails.
So I can see, eventually, combining motor controller logic and DC-DC, with
the power stage on a separate card. After all the logic is going to need
a DC-DC anyway.
But this only makes sense if the volume is high enough that there is a
significant cst savings to combining them and the replacement cost of the
card is cheap enough to make tossing it economical.
I.e. it has to cost less to replace than to repair.
At any rate, we are no where near the volume for this to make sense and I
don't see us getting there in the forseable future.
> Hi Folk's
> Generally combining functionality and not using a modular approach is
> historically a bad idea. Look at the 1945 Philco-Ford TV's and RCA
> where they combined the radio, TV and phonograph with a common power
> The result was each "component" had a 4X MTBF (since they shared a lot
> components that got used when you were using any part of the system).
> We went through the same hysterical (I mean historical
> for marketing porposes (it does initially sell things) combining a DC-Dc
> converter with a battery charger and then combining the charger with the
> motor speed control. Due to the poor reliability of combining things,
> were seperated out later conventionally. Combining things works for
> marketeers but not in reality, generally headed for a fall when you do.
> my EV charger patent 6,218,812 www.uspto.gov
> BTW I saw one of those yellow ribbons today on a big SUV that instead of
> saying "Support the Troops" was "Support My Gastank". Now there's someone
> who's honest.
> Have a renewable energy day,
> Mark in Roanoke, VA
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