Filiberto, Peter, Jeff, Rich Over the last few days, we have successfully installed the Low Noise ESD Driver (D1500129) and its associated field wiring. This unit has 15 individual control lines: 4 bits are associated with switches to connect or disconnect the quadrant drive signals to the HV ESD amplifier that pass through the Low Noise Driver for control 4 bits are associated with switches to select or bypass the pole-zero stages in each quadrant drive path. 4 bits are used to select the output drive mode between High Voltage mode and Low Voltage mode for each quadrant. 2 bits are used to steer the two Parametric Instability (PI) drive inputs to any of the four available quadrants. 1 bit is used to enable or disable the High Voltage ESD amplifier A wiring diagram for the entire ESD system is preliminarily available under D1400177-v4 pending the required DCN process. Details of the Low Noise Driver circuitry are available under D1500129 The serial number of the installed chassis is S1500066. The test results from manufacture are available at this serial number. A test fixture has been supplied that allows manual operation of the low noise driver. Details of the test fixture are available under D1500130 This afternoon, Jeff and I are planning to take detailed transfer functions of the driver for better filter compensation. Jeff has also been working on the needed model updates and control screens.
This is my understanding of the new infrastructure that Jeff has installed for controlling the driver. (If anything in this entry is wrong, please correct me.)
The ETMY BIO screen has been expanded to allow for binary control of the new driver, similar to how coil switching is currently done. See attached screenshot.
"State request" controls whether the driver low-pass filtering is engaged. When engaged the driver filtering is two poles at 2.2 Hz and two zeros at 50 Hz. (See D1500016, "Pole-Zero and Driver").
Changing the state request will automatically engage or disengage digital compensation filters which are installed in FM2, FM6, and FM7 of the ESD output filter modules, just like with the coil switching. FM2 (simLP) is the simulated low-pass response (zpk([50;50],[2.2;2.2],1,"n")), and FM7 (antiLP) is the complement of FM2. FM6 (antiAcq) is just a flat gain of 1.
"Hi/lo voltage" controls whether each ESD quadrant is driven by the Strathclyde driver ("hi volts") or the circuity in the new low-voltage driver ("lo volts").
"Hi volt disconnect" controls whether the Strathclyde driver receives input from the DAC.