Pre-Amp Pcb - Agilent Technologies VS Series Operation Manual

CPLD section with a 6-pin overlay connector (J503) and 14-pin CPLD JTAG
connector (J500)
Audio amplifier section with a 2-pin speaker connector J501
TFT_LCD and Touch Panel interface section with a 33-pin display connector (J602),
4-pin touch panel connector (J601), and 20-pin debug connector (P602)
Power supply section with 3-pin power connector (J401) and 5-pin backlight
connector (J400)
DC-AC daughter PCB with high voltage AC connector CN2
A.2.6 Pre-Amp PCB
The Pre-Amp PCB (Agilent P/N R2107301) functions as an ADC converter for the
spectrometer tube helium and total pressure signals under full software control provided by
the CPU PCB. The Pre-Amp PCB passes all voltages and currents to the ion source section of
the spectrometer tube. The Pre-Amp PCB is soldered directly to a spectrometer tube header.
Pre-Amp PCB circuitry provides:
Digital isolated serial interface with the Motherboard PCB
24-bit sigma-delta analog-to-digital conversion of the signals proportional to:
The Pre-Amp PCB circuitry resides on a stand-alone PCB comprised of four sections:
Digital isolated section with a RJ45-10x10 connector (JR1)
ADC section with 8-pin spectrometer connector (J3)
Power supply section
Ion source's high voltage and high current distribution section with 10-pin
connector (J1) and 6-pin spectrometer connector (J2)
VS Series Component Leak Detector
Helium leak rate generated by an electrometer amplifier in a spectrometer tube
Total (spectrometer tube) pressure generated by the ions of gasses heavier than
helium, collected by an off-target collector plate and amplified by an active low
pass filter stage
24 VDC conversion to ± 15 VDC, ± 12 VDC (the electrometer supply), ± 5 VDC
analog supply for the ADC converter, +5 VDC digital supply and 24 V/5 V DC-
DC conversion for the electrometer Peltier cooler element inside of the
spectrometer tube
Ion source's electrodes voltage supply distribution and filtering
A-7