Battery Related Information - Keysight N9912A Service Manual

Theory of Operation
Grounding and Power
— Reflectometer—switched to low power through state when RF OUT port
receivers are inactive.
— High-Band Pre-amp—switched off when not required.
On the A5 system board, each of the ADC's may be individually switched to a
low power mode when not active.
Load switching is generally transparent to the user. One obvious exception is
the that the source turns off during "retrace" in the CAT and NA modes.

Battery Related Information

Battery Description and Operation
The main battery is an SBS (Smart Battery System) compliant pack of lithium
ion cells.
Refer to "Battery Disposal" on page 1-8 for important information about
replacing and disposing of this battery.
The nominal voltage of the battery is 10.8 volts and normally varies from 9 to
12 volts.
The battery has built-in sensors, a processor, and control circuitry. This is
referred to as the Smart Battery circuitry.
The Smart Battery circuitry communicates battery condition and history
information digitally via a digital Smart Batt Bus. The Smart Battery circuitry is
read-only.
Both the battery charging circuit and the System Monitor read battery
information over the Smart Batt Bus.
The battery temperature reported by the analyzer is based on a sensor inside
the battery. Temperature information is available over the Smart Batt Bus. The
thermistor connection (T) on the battery is not used.
The Smart Battery circuit may shut down the battery when the temperature is
out of the acceptable range or when the battery charge is too low.
See the "Working with the Lithium-Ion Battery" section of the FieldFox User's
Guide for additional information on:
— built in charge level gauge
— the battery information screen
— battery care
Battery Information Screen
Refer to the FieldFox User's Guide for information on how to access this screen.
Most of the items displayed on the screen come directly from the battery via
the Smart Batt Bus. Only the first three items are influenced by the analyzer.
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