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- From: b645zjo@utarlg.uta.edu (Rick Homard)
- Subject: Re: another battery drainage question...
- NewsSoftware: VAX/VMS VNEWS 1.41
- References: <1992Jul20.184424.12250@hubcap.clemson.edu>
- Message-ID: <1992Jul21.212248.7806@utagraph.uta.edu>
- Organization: The University of Texas at Arlington
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- Date: Tue, 21 Jul 1992 21:22:00 GMT
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-
- In article <1992Jul20.184424.12250@hubcap.clemson.edu>, jlysagh@hubcap.clemson.edu (james joseph lysaght) writes...
- >I have a question for those of you who REALY know your HP in regards to
- >power usage. Does anybody know the trade off between turning the calc
- >on and off repeatedly as opposed to leaving it on for a while.
- >Specifically, does the calc use much power turning on? Does the
- >calulator use much power when on, but sitting idle? Which power
- >consumption rate is greater?
- >So, who wants to tackle this one?
- >
- >Jim
-
-
- This info is from Hewlett Packard in some literature comparing the HP48SX
- and the HP28S:
-
- Battery Current:
-
- Operating
-
- Worst case 80 mA (milliamps)
- Typical HP48SX 8 mA
- Typical HP48SX and 1 RAM card 9 mA
- Typical HP48SX and Serial I/O 10 mA
- Typical HP48SX and infrared printing 18 mA
-
-
- Idle
-
- Worst case 20 mA
- Typical HP48SX 3.5 mA
- Typical HP48SX and 1 RAM card 4.5 mA
- Typical HP48SX and I/O port open 6.0 mA
-
- Off
-
- Worst Case 50 uA (microamps)
- Typical HP48SX 11 uA
-
-
- Typical battery life is 6 months.
-
-
-
- RAM card
- Typical battery current
- 128K RAM 1.0 uA
- 32K RAM 0.5 uA
- (Whan installed, cards draw power from HP48SX)
- Typical battery life 23 years.
-
-
-
-
- I don't have info regarding the poweron current draw. I would assume
- this would be greater than the idle current draw initially (obvious).
-
- You can draw your own conclusions from the data above.
-
-
- Rick Homard
-
-