1. FIELDS iCDR – RFS Analog Dennis Seitz 1 Solar Probe Plus FIELDS Instrument CDR RFS Analog Dennis N. Seitz UC Berkeley SSL dseitz@ssl.berkeley.edu

2. FIELDS iCDR – RFS Analog Dennis Seitz Outline 2 Introduction EM Assembly Block Diagram Requirements Changes Testing Peer Review Status

3. FIELDS iCDR – RFS Analog Dennis Seitz FIELDS RFS Analog Location 3 RFS Analog section of DCB Separate power and ground planes Entirely enclosed, top and bottom sides SMA inputs from Preamps

4. FIELDS iCDR – RFS Analog Dennis Seitz FIELDS RFS Analog EM 4

5. FIELDS iCDR – RFS Analog Dennis Seitz RFS Function Diagram 5

6. FIELDS iCDR – RFS Analog Dennis Seitz RFS Analog Section Requirements 6 Input Impedance Meets Requirements 50 Ohms  RTI Noise <7nV/√Hz from 30kHz to 16MHz  4Vpp Bandwidth30kHz to 16MHz  Output Impedance100 Ohms  Thermal Range Survival: -30C to +70C Operational: -25C to +60C  Quiescent Power±6 @ 44mA = 528mW  Radiation 20 krad total dose inside DPU Functional Requirements: Five inputs (V1, V2, V3, V4, SCM) Two independent ADC signal conditioning chains Each ADC chain: Single ended measurement of any selected input Difference measurement of any two V1-V4 selected inputs Selectable high or low gain for V1-V4 inputs Balanced differential drive to ±1V range 12 bit ADC All EEE parts are SQPL, 100krad or better  EEE parts conditionally approved pending SET analyses

7. FIELDS iCDR – RFS Analog Dennis Seitz RFS BB to EM Changes 7 Increased bandwidth margin to >50MHz by replacing CD series multiplexers with HC series Increased gain Decreased noise Added ESD/DDD protection diodes Added SCM input circuit to match TDS and DFB

8. FIELDS iCDR – RFS Analog Dennis Seitz RFS Analog EM Testing - Performance 8 Bench testing All functionality confirmed Input noise: 6.5nV/√Hz Bandwidth: 16 MHz Power consumption confirmed ADC interface performance confirmed

9. FIELDS iCDR – RFS Analog Dennis Seitz DCB/RFS EM Testing 9 Complete EM DCB/RFS Assembly 1.Stand-alone functional and characterization 2.Integration with PA and AEB:

10. FIELDS iCDR – RFS Analog Dennis Seitz Preamp EM Testing – Integration 10 Integrated with complete FIELDS1 I&T

11. FIELDS iCDR – RFS Analog Dennis Seitz DCB/RFS in I&T Setup 11

12. FIELDS iCDR – RFS Analog Dennis Seitz RFS Status and Schedule 12 Two EM units built and tested RFS Analog-only RFS + DCB FM schematic revisions completed 5 peer review recommendations  FM parts procurement in progress  SET analysis and PSA in progress  EM characterization over temperature planned Flight design is on track

13. FIELDS iCDR – RFS Analog Dennis Seitz RFS Backup Slides 13 BACKUP SLIDES

14. FIELDS iCDR – RFS Analog Dennis Seitz RFS Noise + Galaxy Added in Quadrature 14

15. FIELDS iCDR – RFS Analog Dennis Seitz RFS Pre-CDR Peer Review 15 No. Detailed CommentActionStatus 1 Quantify the coupling across the space on the board, to the RFS from the digital circuits. The RFS section is isolated on all layers by a 1/8” wide gap in power and ground planes. Will perform end to end tests of RFS performance. If any crosstalk is identified from digital section we will troubleshoot. √ closed 2Qualify the flight balun transformerIn progress.In progress 3 How and where in the circuit, are you measuring phase relationships? Suggested test method would be with a scope within the circuit, and later when the circuit is closed up in the box. Resolve what phase measurements need to be performed, and what is the specification that needs to be met. There is no phase specification. Any end-to-end phase relationships will be characterized during thermal test and calibrated out. √ closed 4 Evaluate expected degradation in bandwidth with radiation exposure and over temperature. Rad data shows DC changes only, and those are minimal; plenty of AD8001 GBW margin Will run gain and phase response tests to >500MHz to check phase margin Will identify what qualifies as acceptable phase margin. √ closed 5 Is there enough phase margin in the anti-aliasing filter? Will perform analysis and simulation to confirm that positive feedback of filter does not result in inadequate phase margin. √ closed