HP 5973 - Main Board

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8 Electronics
Main board
Main board
The main board is mounted on the outer side of the electronics module. The main
board performs the following functions:
• Receives and decodes digital instructions from the HP-IB/MS control card.
• Sends digital information to the HP-IB/MS control card.
• Generates voltages for the ion source lenses.
• Generates control signals for alternate filament selection, filament emission
current, and electron energy. Generates control signals for quadrupole RF drive,
dc/RF ratio adjustment, dc polarity selection, and all detector voltages.
• Performs analog-to-digital conversion for the coil DIP signal, ion source and
mass filter temperature signals, and foreline pressure or turbo pump speed
signal.
• Monitors the signals from the vacuum system and fans; and monitors the
filament status, HV fault and RF fault signals from the side board. Activates the
shutdown line when the analyzer electronics must be disabled.
• Generates the control signals (on and off) used by the ac board for the high
vacuum pump and calibration valve.
• Generates ± 280 V dc (nominal) power for main board lens amplifiers and side
board dc amplifiers.
• Supplies and controls the power for the ion source and quadrupole (mass filter)
heaters.
• Contains LEDs for the front panel status display.
• Provides 24 V dc power for the cooling fans.