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AUSTRALIAN
NATIONAL UNIVERSITY System Design Note 8.02 Created: 5 April 2000 Last modified: 5 April 2000 |
NIFS SCIENCE DETECTOR WIRING REQUIREMENTS
Mark Downing
Research School of Astronomy
and Astrophysics
Institute of Advanced
Studies
Australian National
University
Revision History
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Revision No. |
Author & Date |
Approval & Date |
Description |
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Revision 1 |
Mark Downing 13 September 1999 |
Jan van Harmelen 01 October 1999 |
Original document. |
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Revision 2 |
Peter J. McGregor 05 April 2000 |
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Reformatted for Word 2000. |
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Contents
4 Science Detector
Wiring Requirements
4.1.2 Minimise
Detector Damage
1 Purpose
This document describes the requirements of the science detector wiring inside the NIFS cryostat. The science detector wiring consists of the detector mounting socket and the detector mounting board, wiring from the detector mounting board through to the external hermetic connector mounted in the cryostat wall. It does not include the external wiring from hermetic connector to the detector controller.
2 Applicable Documents
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Document
ID |
Source |
Title |
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IGPO |
NIFS CoDR Statement of Work |
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RSAA |
NIFS Functional and Performance Requirements Document |
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3 Introduction
The science detector wiring provides the components to safely mount the science detector and to conduct signals from the detector to the external wall of the cryostat.
4 Science Detector Wiring Requirements
The following section details the capability requirements for the science detector wiring.
4.1 Capabilities
4.1.1 Down Time
The NIFS system down time should be less than 1%. Down time of the science detector wiring should be only a small fraction of this value. This requires the selection of high reliability components and the adherence to high reliable construction, handling and assembly techniques.
4.1.2 Minimise Detector Damage
The science detector wiring should be designed so as to minimize damage to the detector. The mounting and dismounting of the detector should be made as easy and as safe as possible so as to avoid damage or deterioration to the detector.
4.1.3 Antistatic Protection
The detector is very sensitive to static damage. Techniques to provide antistatic protection to the detector during assembly, operating and instrument storage should be designed.
4.1.4 Readout Time
The science detector wiring should enable the detector to be read out in less than 5 seconds.
4.1.5 Heat Load
Science detector wiring should have a heat load on the cooling system of TBD.
4.1.6 External Wall Connector
The connector through the external wall of the cryostat has to maintain the high vacuum inside the cryostat. The connector should be of a good quality hermetic type.
4.1.7 Number of Signals
The science detector wiring should provide enough wires to drive the science detector in any foreseeable configuration.
4.1.8 Ease of Assembly
The science detector wiring should enable the Dewar and its components to be easily assembled and disassembled.
4.1.9 HAWAII-2 Detector
The science detector wiring should interface to a HAWAII-2 detector.
4.1.10 High Vacuum
The cryostat has to maintain a vacuum of less than 10-5 Torr at operational temperatures. Science detector wiring should have sufficient low outgassing so as to maintain this high vacuum.
4.1.11 Temperature
The science detector wiring has to operate over a wide range of temperatures from room temperature (300 K) down to 60 K, the lowest temperature the detector will need to operate. The science detector wiring must also withstand temperature cycling between these two temperatures at a maximum rate of 1 K/minute. The science detector wiring shall be capable of surviving a temperature range of -20 to +50 C without damage. It shall also be capable of withstanding without damage a temperature range of -20 to +50 C during transport without damage.
4.1.12 Focuser Movement
The science detector wiring must be flexible enough to allow focuser movement of TBD mm.
4.1.13 Detector Cooling
The science detector wiring must allow the detector to be cooled and temperature stabilized to within ±0.1 K over the range of 60 K to 90 K.
4.1.14 Readout Noise
The science detector wiring should be designed to minimize read noise and should not add a significant part to the total read noise.
4.1.15 Cross Talk
The science detector wiring should be designed to minimize cross talk.
4.1.16 Grounding
The science detector wiring should be designed to reduce ground loops, provide shielding against EMI radiation and should fit in with the general instrument-grounding scheme.
4.1.17 Mechanical Environment
The science detector wiring shall be capable of withstanding all telescope orientations, and telescope slew rates of 2° per second in azimuth and 0.75° per second in elevation, or any combination of these along with rotation of the Cassegrain rotator.
4.2 External Interfaces
There are no external interfaces.
4.3 Internal Interfaces
The following internal interfaces exists.
· Detector Controller Wiring Connector - This interface to the detector controller provides the control signals to drive the science detector.
· Science Detector - This interface is the electrical and mechanical interface to the science detector.
· Cryostat interface - This interface is the mechanical interface to mount the detector wiring.
4.4 Safety Requirements
The safety of the science detector is paramount. Extreme care should be taken in the design so as to minimize damage to the detector. The mounting and dismounting of the detector should be made as easy and as safe as possible so as to avoid damage or deterioration to the detector. The detector should be protected from static damage.
4.5 Requirements Traceability
Table 1 lists each requirement and references the document from which each requirement is derived.
Table 1: Requirements Traceability
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Science Detector Wiring Paragraph |
Engineering Requirement |
Addressed Document |
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4.1.1 |
Down Time |
NIFS CoDR Statement of Work §3.1(c)/2. |
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4.1.2 |
Minimize Detector Damage |
NIFS CoDR Statement of Work §3.1(c)/2. |
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4.1.3 |
Antistatic Protection |
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4.1.4 |
Readout Time |
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4.1.5 |
Heat Load |
TBD |
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4.1.6 |
External Wall Connector |
TBD |
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4.1.7 |
Number of Signals |
TBD |
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4.1.8 |
Ease of Assembly |
TBD |
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4.1.9 |
HAWAII-2 Detector |
NIFS CoDR Statement of Work §3.2 (b)/1. |
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4.1.10 |
High Vacuum |
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4.1.11 |
Temperature |
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4.1.12 |
Focuser Movement |
TBD |
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4.1.13 |
Detector Cooling |
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4.1.14 |
Read Noise |
TBD |
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4.1.15 |
Cross Talk |
TBD |
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4.1.16 |
Grounding |
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4.1.17 |
Mechanical Environment |
5 Qualification Methods
Table 2: Qualification Methods
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Science Detector Wiring Paragraph |
Engineering Requirement |
Qualification Method |
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4.1.1 |
Down Time |
Demonstration |
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4.1.2 |
Minimize Detector Damage |
Analysis |
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4.1.3 |
Antistatic Protection |
Demonstration |
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4.1.4 |
Readout Time |
Measurement |
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4.1.5 |
Heat Load |
Analysis |
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4.1.6 |
External Wall Connector |
Demonstration |
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4.1.7 |
Number of Signals |
Analysis |
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4.1.8 |
Ease of Assembly |
Demonstration |
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4.1.9 |
HAWAII-2 Detector |
Demonstration |
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4.1.10 |
High Vacuum |
Measurement |
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4.1.11 |
Temperature |
Demonstration |
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4.1.12 |
Focuser Movement |
Demonstration |
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4.1.13 |
Detector Cooling |
Measurement |
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4.1.14 |
Read Noise |
Measurement |
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4.1.15 |
Cross Talk |
Measurement |
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4.1.16 |
Grounding |
Analysis |
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4.1.17 |
Mechanical Environment |
Demonstration |