In article ,
mick wrote:

On Thu, 25 Oct 2007 20:32:51 -0300, robert casey wrote:

snip
Okay, how about class AB? That's usually a push pull configuration
where, at or near zero crossing, both devices are conducting. But get
above, say 10% of maximum input signal level, one of the devices stops
conducting, and the other device is doing the work. Lets also say that
this is a 100W amplifier, if you run it with an input signal that makes
only 1 watt (the volume control is set low), then, sure you could call
it a 1 watt class A amp. But that'd be rather silly...

Class B is where there is no class A overlap. Sure, you could have low
quiescent current, but you could easily have crossover distortion. And
it'd sound like a cheap op-amp...

snip


AFAIK classes AB and B are *always* PP, as they both depend on that mode
for cancellation of even harmonics. You just can't do that with SE output.

That is presumably true in audio applications, but it isn't true in all
applications, for example single ended class AB and class B amplifiers
are often used in applications like Television broadcast transmitters.


Regards,

John Byrns

--
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