1. Jun 4, 2013 1 SPP FIELDS Updated block diagrams Fault Tolerant Design

2. Jun 4, 2013 Fault Tolerance Requirement “Solar Probe Plus will achieve mission success at the end of prime mission by returning no less than 64 Gb of science data composed of at least 7 out of 9 of the required measurements (4.1.2.3 -4.1.2.11) collected during 150 hours below 20 Rs, including no less than 5 hours below 10 Rs. “ Since FIELDS measurements represent 4 of the 9, any single point failure in FIELDS is a mission critical failure. 2 FIELDS threshold mission science measurements:

3. Jun 4, 2013 FIELDS fault tolerant design 3 “Sys-6”, TDS serves double duty, serves as DCB for Side 2

4. Jun 4, 2013 Capabilities retained Side 1 failure, Side 2 carries on FIELDS operations –Inboard MAG Produces magnetic field vectors, 3 axes, up to 293 Sa/s –TDS Can deliver DC electric field vectors, DC to 1MSa/s, one axis (V3,V4) Can deliver electric field spectra, up to 1MHz BW, one axis (V3,V4) Requires some re-programming of TDS function –Total loss: SCM QTN and Radio Emissions Side 2 failure, Side 1 carries on FIELDS operations –Outboard MAG Produces magnetic field vectors, 3 axes, up to 293 Sa/s –DFB Produces electric field vectors and spectra, DC to 150 kSa/s, two axes (V1,V2) and V5 Produces SCM vectors and spectra, DC to 150kSa/s, 3 axes –RFS/DCB Produces QTN spectra, 10kHz to 2.5MHz BW Produces Radio Emission spectra, 1MHz to ~19MHz BW –Total loss: TDS 4

5. 5 Block Diagram Jun 4, 2013

6. MEP Stack Up Side 1 –LNPS1 –MAGo (Outboard) –DCB/RFS –AEB1 –DFB Side 2 –LNPS2 –MAGi (Inboard) –TDS –AEB2 Each slice is bolted to S/C Panel 6

7. Jun 4, 2013 Power interface detail LNPS1 7

8. Jun 4, 2013 Power interface detail LNPS2 8

9. Jun 4, 2013 Actuator Interface 9

10. Jun 4, 2013 Level 3 Requirement - Clarification Current L3 max field intensity: 5V/m at 20kHz –Applied to V5 measurements implies signals that are 10s Volts amplitude –Not met with current design of V5 preamp –Should we clarify this requirement as N/A for Eparallel? 10 Current Level 3 Requirement for EFI…

11. Jun 4, 2013 SCM noise floor question A request from DFB to SCM team: –“recommended that the sensitivity of the complete SCM including Preamp be verified before moving forward on the DFB design.” –Meeting SCM noise floor L3 requirement would more power –L3 requirement is 10X the published SCM noise floor Noise floor analysis of SCM preamp, based on –LT1352 preamp LF output stage, noise referred to its input: 14nV/sqrt(Hz) Indicated gain implies ~450nV/sqrt(Hz) at the output –SCM-LF noise floor (at 3kHz): 1E-5 nT/sqrt(Hz) converts to 26nV/sqrt(Hz) Assuming conversion factor of 2.6mV/nT 11