# Presentation: 857701

## Quick Summary of Noise Test Results.
Noise test hardware & software setup.
Earth grounding/shielding scheme utilized for noise tests.
Linear supply ground/shield scheme.
Vicor supply with uRAM active filter ground/shield scheme.
Vicor supply with voltage regulator ground/shield scheme.
Test results.
Conclusion...

**Noise test hardware & software setup.**
**Earth grounding/shielding scheme utilized for noise tests.**
**Linear supply ground/shield scheme.**
**Vicor supply with uRAM active filter ground/shield scheme.**
**Vicor supply with voltage regulator ground/shield scheme.**
**Test results.**
**Conclusion...**

**Vicor Noise Test Results Ver. 8.0**

## Quick Summary ofNoise test Results

**All tests use FNAL focal plane (_fnal) with a readout rate of 6uS/Pixel.**
**Sigma count measurement could change by ~1.5 counts from day to day, however counts would remain the same for the whole day of tests.**
**Lowest noise was accomplished using linear supplies (~5-6 counts Sigma).**
**Sigma remained the same (~6 counts Sigma) when Vicor supplies +5VD, +/-5VA, +/-15VA, -28VA are connected to DHE. +48VA is not connected. +3.3VD is from linear supply.**
**Sigma went up when +3.3VD is from Vicor supply (~11 counts).   This is due to not having an internal uRAM filter in the Vicor supply. (Vicor doesn’t make a +3.3VD Vicor supply with internal uRAM).**
**An external uRAM on the Vicor +3.3VD supply can be used with an decrease in Sigma (~8 counts).**
**A possible compromise is to use a +3.3V voltage regulator at the point of load, driven from another +5VD Vicor RAMPAC (~ 6.5 counts Sigma).**

## Noise Test Hardware Setup

**All noise test were done on shielded DHE conforming to FNAL specifications using FNAL video cable and CCD emulator.**
**Power supply tests ran:**
**Linear supplies conneted to low-noise Monsoon 6-slot DHE.**
**Vicor supplies +5VD, +/-5VA, +/-15VA, & -28VA connected to Shielded Monsoon DHE. Linear supply +3.3VD is connected to low-noise Monsoon 6-slot DHE.**
**All Vicor supplies including unfiltered Vicor +3.3VD connected to low-noise Monsoon 6-slot DHE.**
**All Vicor supplies including Vicor +3.3VD and uRAM Filter connected to low-noise Monsoon 6-slot DHE.**
**All Vicor supplies including a +3.3v voltage regulator driven from Vicor +5VD and connected to low-noise Monsoon 6-slot DHE.**
**Remote sensing was removed & local sensing added.**

## Noise Test Software Setup

**Monsoon is running Fermilab focalplane with Monsoon Command Bar on cyclone:/home/monsoon/cfg/_fnal/.**
**Code has been added to panSaver by Tao to automatically calculate the # of pixels, pedestal voltage (mean) and Sigma.**
**Exposure can be run in continuous loop by using Labview code written by Inga.**
**Short runs (.5Kx2K CCD) with Labview code were used to quickly analyze modifications to test stand.**
**Long runs (2Kx4K CCD) were then used to get a more detailed analysis of the data.**
**Long run readout analysis in panSaver uses 1,165,026 Pixels.**
**Readout time is at 6uS/pixel.**
**All hardware settings are based on Monsoon Command Bar selection: Cube, Front, Normal, 6us, and with either .5kx1k or 4kx2k size ccds.**
**Channel 0 & 2 video inputs are used for readout.**
**Data is also analyzed for a long run using ./noiselast_prepost.sh to validate accuracy of calculated result in panSaver.**
**Data is analyzed visually using DS9 or FV4.2.**

## CCD test rack connects to earth ground thru power strip going to outlet & provides one point of reference for earth ground.
Grounding strap connects Vicor case to rack to bring signal & earth grounds together.
Analog & digital returns are connected to Vicor case to bring the returns to earth ground.
The power supply analog & digital earth grounds are connected together at the Monsoon crate & at the case to tie earth grounds & signal grounds together.

**Grounding strap connects Vicor case to rack to bring signal & earth grounds together.**
**Analog & digital returns are connected to Vicor case to bring the returns to earth ground.**
**The power supply analog & digital earth grounds are connected together at the Monsoon crate & at the case to tie earth grounds & signal grounds together.**

**Earth Grounding & Shielding Schemes Notes**

## Linear Supply Ground/Shield Scheme

## Vicor Supply with Active Filter Ground/Shield Scheme

## Vicor Supply With Voltage RegulatorGround/Shield Scheme

## Linear Supply Test Results FrompanSaver Window

|   |   |   | Channel 0 |  | Channel 2 |  |   |
| --- | --- | --- | --- | --- | --- | --- | --- |
| Test | Date | Test Stand Setup | Mean | RMS | Mean | RMS | Notes/Results |
| Test1 | 14-Mar-07 | Linear supplies are attached to the Shielded  Monsoon DHE. +48van is not connected. See Linear Ground/Shield Scheme. | 80,201 | 5.50 | 82,511 | 5.60 | Get a baseline measurement with shielded test stand attached to linear supply. |
| Test2 | 19-Mar-07 | VICOR supplies are attached to the Shielded  Monsoon DHE except +3.3VD is connected to LINEAR supply. +48van is not connected. FNAL Video cable & emulator is attached.  | 80,304 | 5.65 | 82,593 | 5.56 | Get a measurement with Vicor supply with filtered RAMPACs & +3.3VD linear supply. |
| Test3 | 20-Mar-07 | Same as Test2, 15-Mar-07, except +3.3VD is connected to UNFILTERED VICOR supply.
 | 80,301 | 10.80 | 82,591 | 10.95 | Get a measurement with shielded test stand attached to un-modified Vicor supply. |
| Test4 | 29-Mar-07 | Same as Test 3, 15-Mar-07, except +3.3VD is attached to VICOR supply WITH URAM filter installed. See Vicor with Active Filter Ground/Shield Scheme
 | 80,242 | 8.00 | 82,576 | 8.12 | Get a measurement with shielded test stand attached to Vicor supply including filtered +3.3VD. |
| Test5 | 29-Mar-07 | Same as Test 2, 19-Mar-07 except +3.3VD is being generated by the VICOR +5VD with a VOLTAGE REGULATOR. See Vicor With Volt. Regulator Ground/Shield Scheme | 80,261 | 6.08 | 82,578 | 6.63 | Get a measurement with Vicor supply and Volt. Regulated +3.3vd. |

## Test Results withnoiselast_prepost.sh

**Test Results with****noiselast_prepost.sh**

**Vicor Supply with Linear +3.3VD**

**Vicor Supply with unfiltered Vicor +3.3VD**

## Test Results with noiselast_prepost.sh

**Vicor Supply with****Filtered uRAM +3.3VD**

**Test Results with**** noiselast_prepost.sh**

**Vicor Supply with****+3.3VD Voltage Regulator**

## Conclusion/Next...

- Is the sigma low enough?
- If so:
- Compare grounding/shielding schemes between Monsoon prototype system & low-noise test stand.
- Implement changes at FNAL and run more tests.
- Run more tests:
- Run 2 channels @ 4uS/Pixel.
- Run 1 ccd Acq. Board/8 channels @ 4uS.
- Run 1 ccd Acq. Board/12 channels @ 4uS.
- Run fully loaded DHE, 3 12 ch. CCD & 2 CBB boards/36 channels @ 4uS.
- Load system down with lowest Vicor configuration to see if Sigma will lower with increased current load.
- Implement suggestions from others to lower noise on +3.3VD.