At 11:28 AM 8/7/01 -0500, you wrote:
>Something else that needs to be said here.
>
>Those protection diodes dump to VCC.
>Your VCC rail needs to be able to deal with that.

Good point. Unstated in my described test circuit was a 180 ohm 1/4W
resistor to sink 27mA to allow current to flow into Vdd without
increasing the voltage.

Pretty much *all* regulators behave this way.
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