Welch Allyn PneumoCheck 61000, Service Manual

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Service Manual 610132 Rev. E Pneumocheck Handle Printer/Charger 25
In this state:
i. VA+ and VA- are not present
ii. U12 and U13 are not powered
iii. U8 is not operating
iv. CR1 is oscillating (8Mhz)
v. The CPU clock (pin 22 of U4) is running
(2Mhz)
In normal operation this state will terminate and
return to the sleep state as soon as the p r o c e s s o r
has nothing to do, such as while it is waiting for a
keypress.
d. FULL ON In this state all of the circuitry is turned
on. The charge pump may or may not
be operating.
If everything is correct the power consumption in the
four states should be:
State 1: OFF: Less that 0.1ma, typ 0.001ma
State 2: ASLEEP: Less than 2.5ma, typ 1.6 ma
State 3: AWAKE: Less than 16ma, typ 10ma
State 4: FULL ON: Less than 35ma, typ 25ma
NOTE: That achieving these levels is both a hardware
and a software function. Malfunctioning software can
raise the power to as much as 5ma in State 2 and 70ma
in State 4.
The maintenance mode of the spirometer allows it to be
placed in each state for testing purposes.
2. Power Consumption
Section 3 - Theory of Operation