On Thu, 2009-11-05 at 22:42 +0100, Jo Scherpenisse wrote:
> A speaker with impedance of 8 Ohms means a DC resistance of about 4  Ohms.
> Driving this speaker directly with the drain of a FET to 5 Volt means a 
> sigificant DCpower in the speaker. I would suggest to use a resistor in 
> series, for the max power in the speaker is 0,8 W.
> That means you must limit the DC power (PWM on 50%) to about 0.2 - 0.3 Watt.

Frankly that seems a little wasteful to me. I'd much rather put a cap in
series, that eliminates the DC component but keeps the full swing on the
speaker.

TTYL

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