1. SDR 7 Jun 20001 Associated Electronics Package (AEP) Curtis Ingraham

2. SDR 7 Jun 20002 Associated Electronics Package (AEP) –Mechanical Layout –Thermal Control –Power System –Data Processing Unit –Mass Memory –Imager Interface –Spectrophotometer Interface –Array Photometer Interface –Digital Signal Processor

3. SDR 7 Jun 20003 AEP Mechanical Layout (1) Seven Subassemblies Subass’y = PCB plus Aluminum Frame PCB Frame = Slice of Enclosure Top and Bottom Covers Bottom Subass’y has Mounting Ears Ten Skewer Rods Secure Stack

4. SDR 7 Jun 20004 AEP Mechanical Layout (2)

5. SDR 7 Jun 20005 AEP Mechanical Layout (3) I/O Connectors in Frame at Board Edge Stacking Connectors for Inter-Board Connections –No Motherboard Needed –Simple Mechanical Arrangement –Fewer Connections –Short Signal Paths Good Radiation and EMI Shielding Good Thermal Path –Easy Assembly/Disassembly –Allows Incremental Development

6. SDR 7 Jun 20006 AEP Mechanical Layout (4)

7. SDR 7 Jun 20007 AEP Thermal Control Heat Transfer by Conduction –Component Leads to PCB –PCB to Frame –Frame to Deck Hottest Subassembly at Deck Hottest Components at board edge near Frame At Least One Thermistor per Subass’y Each Thermistor at Hottest Component

8. SDR 7 Jun 20008 AEP Power System (1) DC-to-DC Converters Power Circuit Switching Current Limiting Monitoring

9. SDR 7 Jun 20009 AEP Power System (2) Low Voltage Power Supply (1) –Input Filter –d.c.-to-d.c. Converters Modular Devices 2680R Family Dual Redundant +/-12 volt Converter Dual Redundant +5 volt Converter Independent Inputs Shunt-Wired Outputs Ground Isolation Input Range Exceeds S/C Spec –Output Filter

10. SDR 7 Jun 200010 AEP Power System (3) Low Voltage Power Supply (2) –Input Current Monitors –Relay-Switched 28-V to Array Photometer –Nominal or Redundant Power to Array Photometer –Low-Z Thermal Path to Deck –Two Temperature Monitors –Contained in Shielded Cavity –Proven In IMAGE FUV Instrument

11. SDR 7 Jun 200011 AEP Power System (4) Power Controller –Receives d.c. Power from LVPS –Individually Switched Power Services Flexible Power Control Able to Isolate Abnormal Loads –Voltage and Current Monitors Valuable Diagnostic Information Approx. 106 Analog Housekeeping Channels –Fold-back Current Limiting Protects Load Protects Power System –Two Thermal Monitors

12. SDR 7 Jun 200012 AEP Data Processing Unit (DPU) (1) DPU Functions –Receives Commands –Sends Status –Sends Telemetry –Manages Mass Memory –Manages Power System –Controls Instrument

13. SDR 7 Jun 200013 AEP Data Processing Unit (DPU) (2) DPU Organization –8085 CPU Rad Hard, Simple, Byte wide, Low Power Proven in Space Missions –16 Kilobytes PROM Baseline Flight Software Power Switched (High Power) –128 Kilobytes SRAM Flight Software Execution Settings, Stack, Tables Telemetry DMA Source

14. SDR 7 Jun 200014 AEP Data Processing Unit (DPU) (3) DPU Block Diagram

15. SDR 7 Jun 200015 AEP Data Processing Unit (DPU) (4) DPU Organization (Continued) –128 Kilobytes EEPROM Operating Parameter Tables Static Settings Alternate Flight Software Versions –Command Receiver –Status Telemetry Transmitter –Science Telemetry Transmitter –Command & Data Interface

16. SDR 7 Jun 200016 AEP Data Processing Unit (DPU) (5) DPU Organization (Continued) –I/O for Instrument Control –High Voltage Control –Bank Switching and Memory Map –Watchdog Reset Timer –Diagnostic Test Port

17. SDR 7 Jun 200017 AEP Data Processing Unit (DPU) (6) Command & Data Interface –Three-Wire Serial Interface (Data, Clock, Strobe) –Eight-Bit Address Plus 16-Bit Data –2 Mb/s; about 14 microseconds per command

18. SDR 7 Jun 200018 AEP Mass Memory (MM) (1) One Gigabit –Static RAM –128 Mbytes –Accessible by 8- or 32-Bit Words –Stores Raw and Compressed Science Data Multi-Port –DSP –DPU –Array Photometer –Spectrophotometer –Imager

19. SDR 7 Jun 200019 AEP Mass Memory (MM) (2) MM Block Diagram

20. SDR 7 Jun 200020 AEP Mass Memory (MM) (3) Low Power Error Detection and Correction –Automatic 1-bit Error Correction –2-bit Error Detection –Error Counters –Latchup Detection –Power Isolation? Controlled by DPU

21. SDR 7 Jun 200021 AEP Mass Memory (MM) (4) Buffer Allocation –Controlled by DPU –Circular or Linear –Continuous Fill –Freeze on Event –Anywhere in MM –Several Binary Sizes

22. SDR 7 Jun 200022 AEP Mass Memory (MM) (5) DSP MM Interface –Fast, Memory Mapped, Direct Access, Read/Write –High Priority DPU MM Interface –Slower, Memory Mapped, Direct Access, Read/Write –Low Priority –Bank Switched into 8085 Memory Space –Telemetry by PCVF Blocks

23. SDR 7 Jun 200023 AEP Mass Memory (MM) (6) Imager MM Interface –Fast, Sequential DMA –Write Only –Circular or Linear Buffer

24. SDR 7 Jun 200024 AEP Mass Memory (MM) (7) Spectrophotometer MM Interface –Fast, Sequential DMA –Write Only –Circular Buffer Array Photometer MM Interface –Fast, Sequential DMA –Write Only –Circular Buffer

25. SDR 7 Jun 200025 AEP Imager Interface Controlled by DPU CDI Imager Status Start Signal from DPU or Trigger Fast Transfer to Mass Memory Buffers in Mass Memory

26. SDR 7 Jun 200026 AEP Spectrophotometer Interface Six Channels Integrates Charge from PMT 12-bit A/D Converter per Channel Sampled at 10 kHz per Channel Continuously Fed to MM Circular Buffer Digital Processing of Selected Channel for Sprite Trigger Adjustable Trigger Threshold

27. SDR 7 Jun 200027 AEP Array Photometer Interface +28 Volts from Power Controller DMA Channel to Mass Memory Circular Buffer in Mass Memory Interface Characteristics TBD

28. SDR 7 Jun 200028 AEP Digital Signal Processor (DSP) Fast, Direct Access to Mass Memory Command Block Interface with DPU Details per NCKU