>
>On 29 Jan 02, at 14:28, rich wrote:
>
>< snip >
>
>> To do the job at hand, a zener must exhibit a high dynamic resistance
>> with only a small change in V. Otherwise it would not be able to
>> maintain a constant V as the screen current varies.
>
>No. That's a SMALL dynamic resistance. You want delta V to be small
>with a given delta I.
>
Zener diode A can change it resistance by 5 to 1. Zener diode B can
change its resistance by 100 to 1. Which one provides a wider range of
regulation with current change?
>Dynamic Resistance = (delta V)/(delta I)
>
>Good voltage regulation is "constant V as the ... current varies"...
>Rich has that right, but that's LOW dynamic resistance.
>
A 10?, 10W resistor allows 1A to flow at 10v and 0.1A to flow at 1V.
This seems to be low dynamic resistance.
cheers, George
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
end
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
|