piclist 2004\06\30\193322a >
Thread: Driving ATtiny11 with 9v battery
www.piclist.com/techref/power/batterys.htm?key=battery
flavicon
face BY : David VanHorn email (remove spam text)



At 08:48 AM 6/30/2004 -0400, Mr MCU wrote:

>Well not really - regulation is not needed.  The additional diode
>supplies the reverse polarity protection, and since it is not a shunt
>regulator, there is NO power loss if you put the micro into sleep mode -
>just what the micro would draw.


That's a strong, and WRONG statement.

No matter what the level of current is in a series circuit, if it contains a reverse biased zener, the power converted to heat in the Zener will be I * Vz.

1mA, 5.1V zener, 5.1mW lost as heat in the zener.


If you had said, "not much", I'd agree.
Still I think the Zener shunt is simpler, and less likely to get a newbie into trouble, than what you proposed. It also provides some reverse polarity protection without adding an additional diode.

This is one that would end up in the "bad circuit" pages of "Art of Electronics", I'm afraid.

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

<5.1.1.6.2.20040630182412.01f10858@mail.cedar.net>

In reply to: <40E2B687.3000302@sgi.net>
See also: www.piclist.com/techref/power/batterys.htm?key=battery
Reply You must be a member of the piclist mailing list (not only a www.piclist.com member) to post to the piclist. This form requires JavaScript and a browser/email client that can handle form mailto: posts.
Subject (change) Driving ATtiny11 with 9v battery

month overview.

new search...