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Current Consumption and Program Performance HP15CLE
Message #1 Posted by Thomas Chrapkiewicz on 21 Sept 2011, 1:03 p.m.

Test Units:

15CHHC2010 CNA02130778, Code:2009-08-03

15CLE CNA1310KH3/02290, Code:2011-04-15

External 3V power supply, CR2032 Cells. Fluke 8060 Multimeter

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I have verified that both the HP15CLE and the HP15C2010HHC draw about 20mA when any key is pressed. I tested this with both an external power supply and an externally applied CR2032 cell. They both draw about 20mA when a program (the LBL A + GTO A loop) is running.

Also, when the ON key is pressed to turn the calc off and held, it continues to draw 20mA until released.

Program execution time Performance:

The 15CLE is about 20% faster than the 15C2010HHC unit (also running the LBL A + GTO A loop). I wonder if this is due to code differences or manufacturing/component tolerances.

TomC

      
Re: Current Consumption and Program Performance HP15CLE
Message #2 Posted by Mike Morrow on 21 Sept 2011, 3:52 p.m.,
in response to message #1 by Thomas Chrapkiewicz

It would be interesting to see the results of the Savage Benchmark for your examples. See message 68 in this thread for a listing for the 15C-LE and instructions.

My 15C-LE does the standard 2500 iteration test in about 48 seconds. The original 15C takes 5840 seconds.

            
Re: Current Consumption and Program Performance HP15CLE
Message #3 Posted by Thomas Chrapkiewicz on 21 Sept 2011, 4:56 p.m.,
in response to message #2 by Mike Morrow

I'll look into that.

Further tests have shown a great variance in timing tests. I have not yet determined which machine (or machine) is varying, but the difference now is closer to 1%.

TomC

            
Re: Current Consumption and Program Performance HP15CLE
Message #4 Posted by Thomas Chrapkiewicz on 21 Sept 2011, 5:20 p.m.,
in response to message #2 by Mike Morrow

Both my 15CLE and 15CHHC2010 complete the Savage Benchmark in 50 seconds with 2499.969898.

TomC

      
Re: Current Consumption and Program Performance HP15CLE
Message #5 Posted by DaveJ on 21 Sept 2011, 9:41 p.m.,
in response to message #1 by Thomas Chrapkiewicz

If I designed a battery powered product that worked like that, I would have got the arse!

And I'll say it again, the HP design team were well aware of the issue 2 years ago, so no excuse.

Thankfully it could be fixed with a firmware upgrade.

Dave.

Edited: 21 Sept 2011, 9:41 p.m.


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