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At 04:43 PM 9/23/04 -0700, you wrote:
>attached here is the datasheet of the relay i used (6V). i don't think its 
>possible to supply the coil with greater than 6V. or maybe i just 
>misunderstood the datasheet.

OK, a pull-in voltage of 4.5V so if you are having trouble pulling the 
relay on then your voltage is dropping below that point.  A max coil 
voltage of approx. 6.8V.

With an 18V input to your power supply and a 5V out you are dropping 13V 
across the 7805 and with a 50mA draw for the relay you are dissipating over 
2W just to pull in the relay.  I think your best option for driving this 
would be a small pwm drive.  The inductance should be high enough that even 
a low frequency would work, you could drive a small FET (with proper 
flyback suppression diode, but you should have that already) either from 
the micro or gate a 555 or similar frequency generator.  The 4.5V-6.8V 
range on the coil corresponds nicely to your 12-18V input voltage range 
with a fixed 37% PWM.  If you could know the input voltage and adjust the 
PWM accordingly you could be even better suited (hmm, should even be able 
to do that with an analog circuit).

>i can't find a 5V relay in our local store so i have to live with that 6V 
>relay. also, maybe the voltage regulator is alright. i'll try to reduce 
>the input voltage.

Two questions, What is the thermal impedance of the 7805 case and heatsink 
you are using?  And what is the current draw of the rest of your 
circuit?  Getting rid of that 2W should help at least a little.

To give an example: National quotes  5 C/W  for a TO220 case
Digikey has a 6W heatsink that is rated for ~16 C/W (they have heatsinks 
covering at least 3W to 10W listed for TO220)

That combination gives ~21 C/W which for a 2W reduction in power would 
reduce your junction temperature by 42C.  The interface between the to-220 
and the heatsink will introduce additional thermal resistance so this is a 
conservative estimate.


Robert

" 'Freedom' has no meaning of itself.  There are always restrictions,
be they legal, genetic, or physical.  If you don't believe me, try to
chew a radio signal. "

                         Kelvin Throop, III

It says that it MUST operate down to 4.80V. So, you should
be safe with a 5V supply. It says that it will work up to
130% of the rated power dissipation on the coil. Lets go
through the arithmatic:

Coil is 100 ohms. Rated voltage is 5V. Power is V * I  and
V = I * R so power can also be written V * V / R. The
numbers are then 5*5/100 = 25/100 = 0.25W.

130% of this is 0.325W. The coil resistance has not changed
so we can solve for voltage or 5.7V.

The coil current is one of the reasons your regulator is
getting warm. If the input voltage is 12 and the output is
5, the drop is 7V. 7V * 60ma = 420mW. That is almost a half
watt, just from the relay!

Jim


On Thu, 23 Sep 2004 16:43:10 -0700 (PDT)
 jay marante <jaythesis@yahoo.com> wrote:
> thanks guys...
>  
> attached here is the datasheet of the relay i used (6V).
> i don't think its possible to supply the coil with
> greater than 6V. or maybe i just misunderstood the
> datasheet.
>  
> i can't find a 5V relay in our local store so i have to
> live with that 6V relay. also, maybe the voltage
> regulator is alright. i'll try to reduce the input
> voltage.
>  
> thanks...
>  
> jay
> 
> 
> 
> 
> __________________________________________________
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At 11:24 AM 9/24/04 -0400, you wrote:
>It says that it MUST operate down to 4.80V. So, you should
>be safe with a 5V supply. It says that it will work up to
>130% of the rated power dissipation on the coil. Lets go
>through the arithmatic:
>
>Coil is 100 ohms. Rated voltage is 5V. Power is V * I  and
>V = I * R so power can also be written V * V / R. The
>numbers are then 5*5/100 = 25/100 = 0.25W.

We must be reading different data sheets ;)  The rated voltage is 6V and 
the pull-in (must operate) is 75% of that.  I get 4.5V.

Power is nominally 60ma at 6V or 360mW

>130% of this is 0.325W. The coil resistance has not changed
>so we can solve for voltage or 5.7V.

Which gives a max power of 468mW which for 100 Ohm coil gives 6.84V.


>The coil current is one of the reasons your regulator is
>getting warm. If the input voltage is 12 and the output is
>5, the drop is 7V. 7V * 60ma = 420mW. That is almost a half
>watt, just from the relay!

I must have slipped a decimal point or something on this one.  You've got 
this correct (although off of 5V it will be a little less).Somehow I got 
the power loss 3x higher.  Always triple check your calculations Sigh.

Nonetheless I think the basic conclusions are the same.

Robert



" 'Freedom' has no meaning of itself.  There are always restrictions,
be they legal, genetic, or physical.  If you don't believe me, try to
chew a radio signal. "

                         Kelvin Throop, III

Oooops -

I slipped on the power part. It should have been computed
from 6V, not 5!

On Fri, 24 Sep 2004 12:08:28 -0400
 Robert Adsett <subscriptions@aeolusdevelopment.com> wrote:
> 
> 
> 
> 
> At 11:24 AM 9/24/04 -0400, you wrote:
> >It says that it MUST operate down to 4.80V. So, you
> should
> >be safe with a 5V supply. It says that it will work
> up to
> >130% of the rated power dissipation on the coil. Lets
> go
> >through the arithmatic:
> >
> >Coil is 100 ohms. Rated voltage is 5V. Power is V *
> I  and
> >V = I * R so power can also be written V * V / R. The
> >numbers are then 5*5/100 = 25/100 = 0.25W.
> 
> We must be reading different data sheets ;)  The
> rated voltage is 6V and 
> the pull-in (must operate) is 75% of that.  I get
> 4.5V.
> 
> Power is nominally 60ma at 6V or 360mW
> 
> >130% of this is 0.325W. The coil resistance has not
> changed
> >so we can solve for voltage or 5.7V.
> 
> Which gives a max power of 468mW which for 100 Ohm coil
> gives 6.84V.
> 
> 
> >The coil current is one of the reasons your regulator
> is
> >getting warm. If the input voltage is 12 and the
> output is
> >5, the drop is 7V. 7V * 60ma = 420mW. That is almost
> a half
> >watt, just from the relay!
> 
> I must have slipped a decimal point or something on this
> one.  You've got 
> this correct (although off of 5V it will be a little
> less).Somehow I got 
> the power loss 3x higher.  Always triple check your
> calculations Sigh.
> 
> Nonetheless I think the basic conclusions are the same.
> 
> Robert
> 
> 
> 
> " 'Freedom' has no meaning of itself.  There
> are always restrictions,
> be they legal, genetic, or physical.  If you don't
> believe me, try to
> chew a radio signal. "
> 
>
                        
> Kelvin Throop, III
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
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thanks for the reply guys...
 
ill trim down the input voltage to 12V. but i'll try to work it down to even a smaller input voltage.
 
i don't know the rating of my heatsink. anyway, my final board is already done. i was just curious why such problem and maybe i can work on it without changing my board. maybe the only way to solve it is to find a 5V relay or lower down the input voltage.

Robert Adsett <subscriptions@aeolusdevelopment.com> wrote:
At 11:24 AM 9/24/04 -0400, you wrote:
>It says that it MUST operate down to 4.80V. So, you should
>be safe with a 5V supply. It says that it will work up to
>130% of the rated power dissipation on the coil. Lets go
>through the arithmatic:
>
>Coil is 100 ohms. Rated voltage is 5V. Power is V * I  and
>V = I * R so power can also be written V * V / R. The
>numbers are then 5*5/100 = 25/100 = 0.25W.

We must be reading different data sheets ;)  The rated voltage is 6V and 
the pull-in (must operate) is 75% of that.  I get 4.5V.

Power is nominally 60ma at 6V or 360mW

>130% of this is 0.325W. The coil resistance has not changed
>so we can solve for voltage or 5.7V.

Which gives a max power of 468mW which for 100 Ohm coil gives 6.84V.


>The coil current is one of the reasons your regulator is
>getting warm. If the input voltage is 12 and the output is
>5, the drop is 7V. 7V * 60ma = 420mW. That is almost a half
>watt, just from the relay!

I must have slipped a decimal point or something on this one.  You've got 
this correct (although off of 5V it will be a little less).Somehow I got 
the power loss 3x higher.  Always triple check your calculations Sigh.

Nonetheless I think the basic conclusions are the same.

Robert



" 'Freedom' has no meaning of itself.  There are always restrictions,
be they legal, genetic, or physical.  If you don't believe me, try to
chew a radio signal. "

                         Kelvin Throop, III


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At 12:23 PM 9/24/2004, jay marante wrote:

>thanks for the reply guys...
> 
>ill trim down the input voltage to 12V. but i'll try to work it down to even a smaller input voltage.
> 
>i don't know the rating of my heatsink. anyway, my final board is already done. i was just curious why such problem and maybe i can work on it without changing my board. maybe the only way to solve it is to find a 5V relay or lower down the input voltage.

The regulator heat issue is simply the result of using a linear regulator in a high current application, with high input-output differential. Heat = (Vin-Vout)*Current

On Saturday 25 September 2004 01:32, Dave VanHorn wrote:
> At 12:23 PM 9/24/2004, jay marante wrote:

> >i don't know the rating of my heatsink. anyway, my final board is
> >already done. i was just curious why such problem and maybe i can
> >work on it without changing my board. maybe the only way to solve
> >it is to find a 5V relay or lower down the input voltage.

> The regulator heat issue is simply the result of using a linear
> regulator in a high current application, with high input-output
> differential. Heat = (Vin-Vout)*Current

Indeed. I was building a benchtop power supply from a kit and noted
that the LM317 (TO3 package) used to provide the variable output
voltage was tapped off the transformer secondary at 30 V. This was
OK for low current work (less than an amp) at low voltage (<6V) and
at medium current above 18V. The regulator would get very hot and
simply shut down.

I read the data sheet on the regulator and figured out the solution.

I added in a switch to the transformer tap to use a 15V tap from the
same transformer.  I was then able to draw full current (always over
2A) over the entire voltage range; by flicking the "current boost"
switch. The transformer is rated at 2A... so heavily regulating at
greater current.

A centre-tapped input to the rectifier bridge would have been better
requiring larger diodes, but somewhat too complicated to implement
at the time; more than 20 years ago when I started tinkering, due to
graduate unemployment. 

As a solution to the issue of having alread made PCB's and then
finding that a linear regulator generates too much heat; one could
replace the linear component with a simple switching regulator on a
daughter-board that connects to 3 pads on the PCB designated for the
linear reg.. The input cap and heat sink can probably be down-sized
to make room for the daughter-board if space is tight.

-- 
/"\ Bernd Felsche - Innovative Reckoning, Perth, Western Australia
\ /  ASCII ribbon campaign | I'm a .signature virus!
 X   against HTML mail     | Copy me into your ~/.signature
/ \  and postings          | to help me spread!

any particular part number for the switching regulator, 5V at about 1A from TI that can replace the 7805? thanks...


Bernd Felsche <bernie@innovative.iinet.net.au> wrote:On Saturday 25 September 2004 01:32, Dave VanHorn wrote:
> At 12:23 PM 9/24/2004, jay marante wrote:

> >i don't know the rating of my heatsink. anyway, my final board is
> >already done. i was just curious why such problem and maybe i can
> >work on it without changing my board. maybe the only way to solve
> >it is to find a 5V relay or lower down the input voltage.

> The regulator heat issue is simply the result of using a linear
> regulator in a high current application, with high input-output
> differential. Heat = (Vin-Vout)*Current

Indeed. I was building a benchtop power supply from a kit and noted
that the LM317 (TO3 package) used to provide the variable output
voltage was tapped off the transformer secondary at 30 V. This was
OK for low current work (less than an amp) at low voltage (<6V) and
at medium current above 18V. The regulator would get very hot and
simply shut down.

I read the data sheet on the regulator and figured out the solution.

I added in a switch to the transformer tap to use a 15V tap from the
same transformer.  I was then able to draw full current (always over
2A) over the entire voltage range; by flicking the "current boost"
switch. The transformer is rated at 2A... so heavily regulating at
greater current.

A centre-tapped input to the rectifier bridge would have been better
requiring larger diodes, but somewhat too complicated to implement
at the time; more than 20 years ago when I started tinkering, due to
graduate unemployment. 

As a solution to the issue of having alread made PCB's and then
finding that a linear regulator generates too much heat; one could
replace the linear component with a simple switching regulator on a
daughter-board that connects to 3 pads on the PCB designated for the
linear reg.. The input cap and heat sink can probably be down-sized
to make room for the daughter-board if space is tight.

-- 
/"\ Bernd Felsche - Innovative Reckoning, Perth, Western Australia
\ /  ASCII ribbon campaign | I'm a .signature virus!
X   against HTML mail     | Copy me into your ~/.signature
/ \  and postings          | to help me spread!




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At 09:31 PM 9/24/2004, jay marante wrote:

>any particular part number for the switching regulator, 5V at about 1A from TI that can replace the 7805? thanks...

Digikey carries some integrated switchers that will work as a drop-in for the 7805.
They are pricey, at about $14-$19 IIRC. Very efficient, very cool, very pricey.

Other than that, any of the NS simple switcher buck regs should be fine.

On Saturday 25 September 2004 10:31, jay marante wrote:

[top-post fixed and excessive quoting deleted!]

> Bernd Felsche wrote:
>> Dave VanHorn wrote:
>> > At 12:23 PM 9/24/2004, jay marante wrote:
>> > >i don't know the rating of my heatsink. anyway, my final board is
>> > >already done. i was just curious why such problem and maybe i can
>> > >work on it without changing my board. maybe the only way to solve
>> > >it is to find a 5V relay or lower down the input voltage.

>> > The regulator heat issue is simply the result of using a linear
>> > regulator in a high current application, with high input-output
>> > differential. Heat = (Vin-Vout)*Current

>> As a solution to the issue of having alread made PCB's and then
>> finding that a linear regulator generates too much heat; one could
>> replace the linear component with a simple switching regulator on a
>> daughter-board that connects to 3 pads on the PCB designated for the
>> linear reg.. The input cap and heat sink can probably be down-sized
>> to make room for the daughter-board if space is tight.

> any particular part number for the switching regulator, 5V at
> about 1A from TI that can replace the 7805?

No single component will replace it, AFAIK. Hence _daughter_board_.
Most semiconductor manufacturers make switchmode controllers. The
high current output requirements are usually met by using an
external power transistor, switched by the controller chip.

It shouldn't take you long to find reference material including
sample applications on the web site of your preferred silicon
pusher.

-- 
/"\ Bernd Felsche - Innovative Reckoning, Perth, Western Australia
\ /  ASCII ribbon campaign | I'm a .signature virus!
 X   against HTML mail     | Copy me into your ~/.signature
/ \  and postings          | to help me spread!

At 07:31 PM 9/24/04 -0700, you wrote:
>any particular part number for the switching regulator, 5V at about 1A 
>from TI that can replace the 7805? thanks...

1 Amp with a 7-13V drop, not much wonder you are getting warm. That would 
be a 28 to 52 C rise from the heatsink to ambient for a good (4 C/W) TO-220 
heatsink. Add in junction to case rise of 35 to 65C and you would be 
running a heatsink of 50 to 70C (definitely hot to the touch) and a 
junction temp of 85 to 135C.  Nationals data sheet indicates a maximum 
junction temperature of 125C so you would clearly be in danger of shutdown 
at the higher voltage inputs.

As far as a switching replacement you might take a look at these

http://focus.ti.com/lit/ds/symlink/pt78st105.pdf

I've not used them so I can't say how good they are.  You would need to 
check their thermal performance but a quick glance looks good.  I'm not 
100% sure they fit in a to-220 outline but if I am remembering correctly 
the rep that pointed them out to me once upon a time said they either did 
or were close.

Robert

" 'Freedom' has no meaning of itself.  There are always restrictions,
be they legal, genetic, or physical.  If you don't believe me, try to
chew a radio signal. "

                         Kelvin Throop, III

will Digikey sell in low volume orders, like 3ea or 5 ea?
Would this be true of some but not all items?

-----Original Message-----
From: Dave VanHorn [mailto:dvanhorn@dvanhorn.org]
Sent: Friday, September 24, 2004 8:36 PM
To: AVR-Chat@yahoogroups.com; AVR-Chat@yahoogroups.com
Subject: Re: [AVR-Chat] 7805 power supply



At 09:31 PM 9/24/2004, jay marante wrote:

>any particular part number for the switching regulator, 5V at about 1A from
TI that can replace the 7805? thanks...

Digikey carries some integrated switchers that will work as a drop-in for
the 7805.
They are pricey, at about $14-$19 IIRC. Very efficient, very cool, very
pricey.

Other than that, any of the NS simple switcher buck regs should be fine.





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--- In AVR-Chat@yahoogroups.com, "stevech" <stevech@s...> wrote:

> will Digikey sell in low volume
> orders, like 3ea or 5 ea? Would
> this be true of some but not all
> items?

Digi-Key sell just about everything in their catalog in ones. (The 
exceptions are things like washers where you have to buy 100, which 
is a couple of dollars.) There is a $5.00 processing fee for orders 
under $25.00. The same general idea applies to Mouser.  All this 
information and more is at their respective Web sites, where you can 
search for the parts you need and place your order.

Graham.

At 12:37 AM 9/25/04 -0400, you wrote:
<snip>

>As far as a switching replacement you might take a look at these
>
>http://focus.ti.com/lit/ds/symlink/pt78st105.pdf
>
>I've not used them so I can't say how good they are.  You would need to
>check their thermal performance but a quick glance looks good.  I'm not
>100% sure they fit in a to-220 outline but if I am remembering correctly
>the rep that pointed them out to me once upon a time said they either did
>or were close.

A followup to an old post on the assumption there are a few people here who 
may be interested.  I ran across this switching replacement for a 7805 
while looking for shunts and associated panel meters.

http://store.datel.com/cgi-bin/datel.storefront/417488ce057cc09c271d0c9f89420719/UserTemplate/1?BodyContent=newdpm#dpm1

I particularly like the wording "Prices start at $4.95 for huge quantities".

Robert

" 'Freedom' has no meaning of itself.  There are always restrictions,
be they legal, genetic, or physical.  If you don't believe me, try to
chew a radio signal. "

                         Kelvin Throop, III

We have a chain of stores locally that sells loads of things, all at 1UK 
pound. Most interesting lately were some mobile telephone chargers 
intended for use in a car.They contained a complete switching regulator 
- already set to 5V and capable of delivering a few hundred milliAmps 
from anything up to about 20V in.

I just took out the small circuit board and shoved the whole thing on my 
robot. Now I dont have to be careful to avoid touching an extremely hot 
regulator and the current drawn from the battery pack is a quarter of 
the processor board current - I could hardly ask for more.

Pete Harrison
http://micromouse.cannock.ac.uk/

i found the UCC383-5 from TI. it is pin compatible with the 7805. input voltage from 5.5 to 9 V with 3 amps max output.

Zack Widup <w9sz@prairienet.org> wrote:I got a dozen or so LT1074/LT1076's very cheap at a hamfest. They are 5-pin TO-220 devices.  These are great for a switching supply that puts out 5 volts for 10 to 40 volts in. With a split inductor circuit you can get 10 amps out at 5 volts with the 1074.  I usually only need a couple amps at most for a circuit, so the straight inductor circuit Linear has in their data sheet works well enough for me.
 
Zack

----- Original Message ----- 
From: Robert Adsett 
To: AVR-Chat@yahoogroups.com 
Sent: Monday, October 18, 2004 10:38 PM
Subject: Re: [AVR-Chat] 7805 power supply


At 12:37 AM 9/25/04 -0400, you wrote:
<snip>

>As far as a switching replacement you might take a look at these
>
>http://focus.ti.com/lit/ds/symlink/pt78st105.pdf
>
>I've not used them so I can't say how good they are.  You would need to
>check their thermal performance but a quick glance looks good.  I'm not
>100% sure they fit in a to-220 outline but if I am remembering correctly
>the rep that pointed them out to me once upon a time said they either did
>or were close.

A followup to an old post on the assumption there are a few people here who 
may be interested.  I ran across this switching replacement for a 7805 
while looking for shunts and associated panel meters.

http://store.datel.com/cgi-bin/datel.storefront/417488ce057cc09c271d0c9f89420719/UserTemplate/1?BodyContent=newdpm#dpm1

I particularly like the wording "Prices start at $4.95 for huge quantities".

Robert

" 'Freedom' has no meaning of itself.  There are always restrictions,
be they legal, genetic, or physical.  If you don't believe me, try to
chew a radio signal. "

                         Kelvin Throop, III



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Hi Everyone,

I'm looking for a good lithium battery for my project. I'm using ATMega8535L and this battery need to last me for a long time. I need at least above 7AH or capacity. I found Sonnenschein website that offer such a battery but I cant get it here locally. Can anyone there recommend me?

How about the voltage drop for the lithium battery? Cos I need to maintain 3V for my uP to run.

Thanks.

Regards,

N2

Do you Yahoo!?
Yahoo! Mail - You care about security. So do we.

S&G Photo (http://www.sg-photo.com/) used to carry a BA-5513 that was 
7.5Ah.

Mike


--- In AVR-Chat@yahoogroups.com, Andrew Lim <normaxcite@y...> wrote:
> I'm looking for a good lithium battery for my project. I'm using 
ATMega8535L and this battery need to last me for a long time. I need 
at least above 7AH or capacity.

--- In AVR-Chat@yahoogroups.com, Andrew Lim <normaxcite@y...> wrote:
> 
> Hi Everyone,
> 
>  
> 
> I'm looking for a good lithium battery for my project. I'm using 
ATMega8535L and this battery need to last me for a long time. I need 
at least above 7AH or capacity. I found Sonnenschein website that 
offer such a battery but I cant get it here locally. Can anyone there 
recommend me? 
> 

Digi-Key lists D as 6500 mah

If you use a 4 D size batteries you can get over 4 volts 

Will that do ?

BTW, you didn't mention cycle times and deep discharging.   all 
batteries have a curve of available power that falls after repeated 
charging.




Dave

A single cell LiIon battery is about 4.1V fully charged and
has used a very large percentage of its capacity by the
time it drops to 3V. 

Your circuit needs to be able to monitor the voltage and
shut down or provide other warnings when the battery
voltage goes too low.

Most cells or packs have an internal protective circuit. It
shuts off from the outside world under several conditions.
One is excessive load current. Another is when the battery
becomes discharged too far (voltage is too low). LiIon
batteries require rather careful charging. There are a
variety of ICs that will do this, but you need to do it
correctly to get reasonable performance.

A vert common cell size is 2.2AHr. You could use 3 in
parallel and get very close to your requirement of 7AHr.

The company I work for is paying about $45US (or more) for
a pack consisting of two series connected 2.2AHr LiIon
cells in small quantities (around 100 packs at a time).

Jim

On Tue, 19 Oct 2004 20:58:14 -0700 (PDT)
 Andrew Lim <normaxcite@yahoo.com> wrote:
> 
> Hi Everyone,
> 
>  
> 
> I'm looking for a good lithium battery for my project.
> I'm using ATMega8535L and this battery need to last me
> for a long time. I need at least above 7AH or capacity. I
> found Sonnenschein website that offer such a battery but
> I cant get it here locally. Can anyone there recommend
> me? 
> 
>  
> 
> How about the voltage drop for the lithium battery? Cos I
> need to maintain 3V for my uP to run.
> 
>  
> 
> Thanks.
> 
>  
> 
>  
> 
> Regards,
> 
> N2
> 
> 		
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Many LiIon batteries are spec'd to drop to 50% capacity
after 300 charge cycles.

Jim

On Wed, 20 Oct 2004 17:11:55 -0000
 "Dave Mucha" <dave_mucha@yahoo.com> wrote:
> 
> 
> 
> 
> 
> 
> --- In AVR-Chat@yahoogroups.com, Andrew Lim
> <normaxcite@y...> wrote:
> > 
> > Hi Everyone,
> > 
> >  
> > 
> > I'm looking for a good lithium battery for my
> project. I'm using 
> ATMega8535L and this battery need to last me for a long
> time. I need 
> at least above 7AH or capacity. I found Sonnenschein
> website that 
> offer such a battery but I cant get it here locally. Can
> anyone there 
> recommend me? 
> > 
> 
> Digi-Key lists D as 6500 mah
> 
> If you use a 4 D size batteries you can get over 4 volts 
> 
> Will that do ?
> 
> BTW, you didn't mention cycle times and deep
> discharging.   all 
> batteries have a curve of available power that falls
> after repeated 
> charging.
> 
> 
> 
> 
> Dave
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
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> Digi-Key lists D as 6500 mah
> 
> If you use a 4 D size batteries you can get over 4 volts 


Please note that rechargable D batteries might be C batteries in 
larger containers and selling for a large premium above rechargable C 
batteries.  This kind of nonsense was typical with NiCads.  It may be 
different with LiIon: It may not.  Check the amp Hour ratings of both 
sizes. If they're nearly the same, then this Mickey-Mouse game 
continues on.  Real D's should have at least 50% more AmpHr's than C 
size batteries.

--- In AVR-Chat@yahoogroups.com, "alan_probandt" <alan_probandt@y...> 
wrote:
> 
> > Digi-Key lists D as 6500 mah
> > 
> > If you use a 4 D size batteries you can get over 4 volts 
> 
> 
> Please note that rechargable D batteries might be C batteries in 
> larger containers and selling for a large premium above rechargable 
C 
> batteries.  This kind of nonsense was typical with NiCads.  It may 
be 
> different with LiIon: It may not.  Check the amp Hour ratings of 
both 
> sizes. If they're nearly the same, then this Mickey-Mouse game 
> continues on.  Real D's should have at least 50% more AmpHr's than 
C 
> size batteries.

Here's the listing			
	

SIZE     Volts   MAH	part #		
AAA 	1.2	550	P011-ND
AAA 	1.2	650	P051-ND
AAA 	1.2	700	P213-ND
AAA 	1.2	700	P008-ND
L-AAA 	1.2	650	P012-ND
L-AAA 	1.2	750	P216-ND
4/5  AA	1.2	115	P013-ND
AA 	1.2	1500	P015-ND
AA 	1.2	1550	P060-ND
AA 	1.2	2000	P220-ND
4/5 A	1.2	2000	P010-ND
A 	1.2	2100	P017-ND
4/3 A	1.2	3700	P018-ND
4/3 A	1.2	4200	P214-ND
4/5  SC	1.2	200	P020-ND
SC 	1.2	3000	P021-ND
D 	1.2	6500	P019-ND

The D size is pretty high as compared to the rest.

Dave

Hi All,
 
Thanks for the great input. I'm sorry that I left out one important information. I'm looking for non-rechargeable Lithium battery which Sonnenschein has it.
 
Sorry about that. 
 
N2

Dave Mucha <dave_mucha@yahoo.com> wrote:

--- In AVR-Chat@yahoogroups.com, "alan_probandt" <alan_probandt@y...> 
wrote:
> 
> > Digi-Key lists D as 6500 mah
> > 
> > If you use a 4 D size batteries you can get over 4 volts 
> 
> 
> Please note that rechargable D batteries might be C batteries in 
> larger containers and selling for a large premium above rechargable 
C 
> batteries.  This kind of nonsense was typical with NiCads.  It may 
be 
> different with LiIon: It may not.  Check the amp Hour ratings of 
both 
> sizes. If they're nearly the same, then this Mickey-Mouse game 
> continues on.  Real D's should have at least 50% more AmpHr's than 
C 
> size batteries.

Here's the listing                  
      

SIZE     Volts   MAH      part #            
AAA       1.2      550      P011-ND
AAA       1.2      650      P051-ND
AAA       1.2      700      P213-ND
AAA       1.2      700      P008-ND
L-AAA       1.2      650      P012-ND
L-AAA       1.2      750      P216-ND
4/5  AA      1.2      115      P013-ND
AA       1.2      1500      P015-ND
AA       1.2      1550      P060-ND
AA       1.2      2000      P220-ND
4/5 A      1.2      2000      P010-ND
A       1.2      2100      P017-ND
4/3 A      1.2      3700      P018-ND
4/3 A      1.2      4200      P214-ND
4/5  SC      1.2      200      P020-ND
SC       1.2      3000      P021-ND
D       1.2      6500      P019-ND

The D size is pretty high as compared to the rest.

Dave








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