1. Selda HeavnerFIELDS iPDR – Antenna Electronics Board Solar Probe Plus FIELDS Instrument PDR Antenna Electronics Board Selda S. Heavner U.C. Berkeley selda@ssl.berkeley.edu 1

2. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB Requirements –AEB shall provide ± 15V Floating Voltage to V1, V2, V3, V4 and V5 preamps (heritage RBSP) Input is +5V Analog Efficient >60% Synchronized to 300KHz Isolated secondary voltages 5% output regulation –AEB shall regulate Preamp ±6 V from LNPS to ±5V –AEB shall provide the power and the control signal for the latching relay controls on the preamps (On V5 heater resistors) 3 bias impedances. –AEB shall be a nexus for MF and HF signals from preamp. The signals shall not have any traces on the board. The signals shall arrive on a DB connector and via coax cables (RG316). The signals shall be then connected to TDS, RFS and DFB (also DB connectors). –AEB shall provide housekeeping signals to DCB via multiplexer (preamp temperature, AEB temperature, DAC voltages) 2

3. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB Requirements 3 AEB Specifications Cont. (heritage: THEMIS, RBSP) Receive Preamplifier Signals –Voltage Range : ± 115V w.r.t chassis –Large Signal Dynamic Range and Bandwidth: 20Vp-p, DC-300Hz, with less than 40dB added harmonic content. Floating Ground Driver (heritage: THEMIS, RBSP) –AEB provides the reference source for each floating ground used by the Preamps –Input : PAn_LFOUT (preamp signal) –Input Filter: 300Hz –Output Voltage Level: ± 60V with respect to AGND –Output : References floating ground supply (± 15VDC)

4. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB Requirements 4 BIASING VOLTAGES (V1-V4) AEB shall provide programmable biasing voltages to the V1-V4 preamps as follows: BIAS (whip): ± 40 w.r.t preamp output HEATSHIELD: ± 40 w.r.t preamp output STUB: ± 40 w.r.t preamp output BIASING VOLTAGES (V5) AEB shall provide a provide a programmable biasing voltage to the V5 preamp as follows: BIAS (sensor):± 40 w.r.t preamp output

5. Selda HeavnerFIELDS iPDR – Antenna Electronics Board SPP FIELDS AEB and Heritage Designs Channel requirements and design are the same: CLUSTER, POLAR and THEMIS. No changes on BIAS, STUB, HEATSHIELD and Floating GND driver. AEB generates the floating voltages (15VF) DAC (AD5544) can no longer be used due to process changes in Analog Devices. A new DAC that is space qualified is incorporated in the design (DAC121S101). AEB will be the transfer station for MF and HF signals from the preamp. These signals will not have traces the on the board. Connected via coax cables. Latching relay control for the PA bias resistors will be on AEB. DCB or TDS will send the command. Power switch will occur on AEB. Operating max temperature is expected to be higher. Parts selected can handle higher temperature. 5

6. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB1 BLOCK DIAGRAM 6

7. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB 2 BLOCK DIAGRAM 7

8. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB 1 Coax Cable and Connector DIAGRAM 8

9. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB 2 Coax Cable and Connector Diagram 9

10. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB 1 POWER BLOCK DIAGRAM 10

11. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB 1 POWER FLOATING SUPPLY 11

12. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB 2 POWER BLOCK DIAGRAM 12

13. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB 2 POWER FLOATING SUPPLY 13

14. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB FLOATING POWER 14 AEB Breadboard Power Results –The supply is 68% when powered by 3.3V Digital at nominal load –The supply efficiency is expected to rise since MAX256 will be connected to 5V Analog from LNPS. –MAX 256 3W H-bridge driver Has an internal oscillator so if SYNC signal is lost from DCB it will still run Short circuit protection Thermal shutdown Used on RBSP, submitted to APL Jan 2013 for approval Voltage (V)Load Current (mA)Power (W) FV1 P15V 14.0954.150.05849425 FV1 N15V 14.0914.510.06355041 FV2 P15V 14.595.260.0767434 FV2 N15V 14.585.330.0777114 VIN 3.3V124.80.411

15. Selda HeavnerFIELDS iPDR – Antenna Electronics Board LAYOUT and PARTS LAYOUT –AEB ETU Layout started in October 2013. MASS and POWER –± 12V and ± 100V is now generated by LNPS. Helped mass. –Power updates are submitted to LNPS. No issues. PARTS –MAX256 approval submitted to APL January 2013 –DAC121S101 has not been used on heritage designs. Submitted to APL and approved. 12-bit, low power –Multiplexer on AEB selected: UT16MX110. ISSUES –Connecting 12V to heater resistor on preamp (V5)- resolved at Peer Review –DAC needs to be at mid-scale when powered on. New DAC is at zero after power on reset. 15

16. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB Peer Review Recommendations 16 No.Detailed CommentActionStatus 1 Put a relay on AEB to turn on and off the heater. See if RC filtering is necessary and look into +/- supply instead of single supply to see if that will reduce possible EMI. Added RC filtering on AEB ETU schematic open 2 Add “on box bias on V5” on chart, level 4 requirement update Added relays on AEB schematic closed 3 Remove LF coax requirement from AEB and Redo coax diagram. Updated block diagram.closed 4 What happens to the output when the sync is removed from AEB? Is it a smooth transition? Test and document Test at ETU level by removing the sync signal. open 5 Test DAC turn on characteristics when connected to preamp box. What happens when the DAC comes on at 0 volts instead of mid-scale? Test at ETU level integration with preamp. open 6 Question about the output stage of the heritage design: floating ground driver circuit (Q19, Q20). Heritage design. It has been used on several missions no changes required. closed No RFAs

17. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB Status and Schedule  AEB Engineering Test Unit (ETU) design is completed. Schematic is finalized after the peer review.  AEB ETU layout started end of October 2013.  AEB ETU Bill of Materials submitted to Quality Assurance.  ETU parts procuring began. 17

18. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB Backup Slides BACKUP SLIDES 18

19. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB CHANNEL(n) BLOCK DIAGRAM 19

20. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB CHANNEL 5 BLOCK DIAGRAM 20

21. Selda HeavnerFIELDS iPDR – Antenna Electronics Board AEB LAYOUT 21