41CL User Manual
© 2019, Systemyde International Corporation
6
With these features, however, come some drawbacks:
•
Power consumption is higher, at least while the calculator is off or in light sleep
(between keystrokes). Where the original HP-
41
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d
a
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,
t
he
41CL
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s
a
bout
110
μA.
Thi
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a
d
t
o
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duc
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.
•
The original HP-41 could retain memory contents for several minutes while the
batteries were changed. Because of the higher current consumption, the 41CL only
retains the memory contents for a few seconds while the batteries are out. For this
reason, you should probably have an extra battery holder ready to go when changing
batteries.
•
The advanced technology used in the 41CL is a double-edged sword. The Flash
memory, as well as the programmable logic devices used to implement the NEWT
microprocessor, only guarantee data retention for 20 years.
The table below shows the typical current drain for the 41CL under various conditions.
The serial port is powered up whenever it is connected to something with a valid signal
level.
No Time Clone installed
Time Clone installed
Calculator State
Serial port
off
Serial port
on
Serial port
off
Serial port
on
Off
110
μA
3.6 mA
340
μA
3.8 mA
Light Sleep
(between key presses)
3.6 mA
7.1 mA
3.8 mA
7.3 mA
Running (1x) (Note 1)
7.1 mA
10.6 mA
7.3 mA
10.8 mA
Running (50x) (Note 2)
12.1 mA
15.6 mA
12.3 mA
15.8 mA
Flash Erase (Note 3)
46.0 mA
49.5 mA
46.2 mA
49.7 mA
Note 1: Measured during a CAT 2 operation.
Note 2: Measured during a normal (not CPONLY mode) FLCHK? operation. See the
41CL Update Functions
for details.
Note 3: This peak current lasts for less than 500 mS.
