Transcript LAT-MD-08398-01

LAT-MD-08398-01
28 July 2006
GLAST Large Area Telescope
Gamma-ray Large
Area Space
Telescope
LAT Level Requirement Sell-off
Package for
LVP159/LPS598 – DC Voltage Tolerance
Requirement Owner: David Nelson
Approval Date:
Approved By:
LAT Docs No:
LAT Requirement Sell-off Package
LAT-MD-08398
LAT-MD-08398-01
28 July 2006
LVP159/LPS598 – DC Voltage Tolerance





Requirement:
The LAT shall tolerate without damage or degradation DC voltages
greater than 15.0 volts and less than 40.0 volts.
Verification Method: A5
Verification Plan:
1) This requirement has a waiver submitted to NASA. This analysis
sets the minimum voltage to 18.5 volts. The CCR number is 433-0357.
2) Analysis will show that all of the components are rated for 40 volt
operation.

Test Script Run Info:

Worst Case Measured Data: N/A

Margin: N/A

Test/Analysis Summary: Analysis shows that the minimum voltage is
18.5 volts. All subsystem assemblies are rated to 40 volts.
LAT Requirement Sell-off Package
2
LAT-MD-08398-01
28 July 2006
LVP159/LPS598 – DC Voltage Tolerance

Analysis Report/Test Report Doc #(s):
–
–
CCR # 433-0357 is the analysis for 18.5 volt operation.
The 40 volt operation was successfully tested on each of the following subassemblies:
•
Tower Power Supply, LAT-DS-01482
–
•
Crate Power Supply, LAT-DS-02390
–
•
The test procedure for the Crate Power Supply is LAT-TD_01673 paragraph 5.4.1-35
GASU Power Supply, LAT-DS-02413
–
–
The test procedure for the Tower Power Supply is LAT-TD-01652 paragraph 5.5.2-6
The test procedure for the GASU/ACD Power Supply is LAT-TD_01727 paragraph 5.4.1-36
The PDU 40 volt compliance is by analysis.
•
•
The PDU Assembly schematic diagram is LAT-DS-01696.
The PDU CCA schematic is LAT-DS-02127.
•
•
•
LAT-DS-02127 sheet 6 of 66, PDU_3_3_V_PS is the schematic of the 28V to 3.3V power converter.
There is a series of capacitors, C42-C47 & C49 which is rated at 50V
An input filter, ARF461 which is rated at 80 volts.
–
•
A DC-DC converter, MAX-724, rated at maximum of 45 volts
–
•
http://pdfserv.maxim-ic.com/en/ds/MAX724-MAX726.pdf
Two power FETs are used to switch spacecraft power to loads are rated at 60V
–
–
•
http://www.irf.com/product-info/datasheets/hirel/arf461.pdf
http://www.irf.com/product-info/datasheets/data/irhna597064.pdf
http://www.irf.com/product-info/datasheets/data/irhnj597034.pdf
All wire used is MIL-W-22759 rated at 600V
LAT Requirement Sell-off Package
3
LAT-MD-08398-01
28 July 2006
LVP159/LPS598 – DC Voltage Tolerance

Compliance Statement: LAT Complies

NCRs/JIRAs: None
LAT Requirement Sell-off Package
4