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Clonix battery consumption
Message #1 Posted by Claudio Maccioni on 11 Jan 2004, 2:04 p.m.

Diego, i have just transformed two Memory modules into one DoubleMemory module, so now i wish to use the other Memory module case to mount your wonderful Clonix, but i'm worried about the power consumption.

With 21.5 mA, how long do the batteries endure? Are there eventually any others microCpu with lower mA consumption? I know both the Microchip mCpu both Atmel mCpu, but they have high power consumption at these speed.

Is possible to reduce the MHz of the Clonix's clock with HP41C at standard clock speed (obviously with changes into the program)?

Thanks you very much for your answers and for your wonderful job in Clonix project.

      
Re: Clonix battery consumption
Message #2 Posted by Diego Diaz on 12 Jan 2004, 5:18 a.m.,
in response to message #1 by Claudio Maccioni

Hi Caludio,

This 21.5mA value were measured at battery positive terminal, and some further detail will hopefully help to understand this issue, I'll try to explain the current "state of the art" in Clonix-41 power management:

The power requirements has been one my major concerns since the begining of this project. As you probably know, Clonix hardware design have suffered several minor mods since it was first released for beta-testing by mid Dec.

Beta units used a series diode(s) in the V+ line.

A first mod substituted the diode(s) for a 47 Omh resistor, actually only one Clonix unit is equiped with such resistor, and it's one of my own units.

All the Clonix's that have been sold or traded "wear" a 100 Ohms resistor, wich means a reasonable compromise between the operative lower limit (about 270 Ohms for a 1.7x HP-41, or 360 Omhs for a 1x machine) for low power requirements, and the system stability.

Whit this in mind, the latest version of the Clonix-41 manual, properly reflects those changes. Alas, it hasn't been published yet due to other mods related with the 6 pages and RAM upgrading. It will hopefully be on-line during this week.

Some technical aspects regarding HP-41 power supply, must be taken into consideration prior to look at "mA" figures.

- The DC/DC convertor IC draws more current from the batteries as the voltage of said batteries decreases. Thus, the batery terminal in not approprite for an accurate power consumption measurement, as Current is rising up while Voltage is falling down.

- The V+ line at I/O port is the real line from wich Conix (or any other module) draws its power from. Measures made at this point are quite more reliable and there is where they've been done for the latest documentation.

The figures at this point are almost independent from battery Voltage, and shows up the following values:

SLEEP: <100ľA

STAND-BY: <500ľA

ON: 13.5mA

Should you still need to reduce this figures and (as stated above) *only* for 1x machines, resistor values of 220 Ohms are acceptable, lowering the ON state power drain to the 9.5mA mark. Further reduction is possible but by no means advisable... ;-)

Hope this helps.

Diego.

            
Re: Clonix battery consumption
Message #3 Posted by Claudio Maccioni on 14 Jan 2004, 3:50 a.m.,
in response to message #2 by Diego Diaz

Thank you very much for the explanations. I attend with eagerness your next release in order to begin to mount all.

Claudio

                  
Re: Clonix battery consumption
Message #4 Posted by Diego Diaz on 14 Jan 2004, 5:55 a.m.,
in response to message #3 by Claudio Maccioni

Hi Claudio,

I'm glad to know that my info is usefull. Anyhow I don't think I quite understand your last statement:

Quote:

"I attend with eagerness your next release in order to begin to mount all"

Well, I'm not planning any "next release" as Clonix-41 is a finished project. Some software improvements may arise but the "Hardware" will ramain the same. Should a specific user ask for a Low Power version (some have already done) I'll build them up, labelled with a Silver decall instead a Golden one for identification purposes.

Hope this clarifies the Clonix project status.

Cheers from Spain.

Diego.


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