THEMIS Instrument CDR 1 UCB, April 19-20, 2004 Boom Electronics Board (BEB) Engineering Peer Review Apr. 20, 2004 Hilary Richard

THEMIS Instrument CDR 2 UCB, April 19-20, 2004 BEB Requirements Functional Requirements Spin Plane Booms, for each provide: –Floating Ground Driver –“Bias”, “Guard”, “Usher” programmable potentials –“Braid” programmable, switchable potential –AC test signal source Axial Booms, for each provide: –Floating Ground Driver –“Bias”, “Guard”, “Usher” programmable potentials –AC test signal source

THEMIS Instrument CDR 3 UCB, April 19-20, 2004 BEB Requirements, con’t.

THEMIS Instrument CDR 4 UCB, April 19-20, 2004 BEB Analog Electronics

THEMIS Instrument CDR 5 UCB, April 19-20, 2004 BEB Block Diagram

THEMIS Instrument CDR 6 UCB, April 19-20, 2004 Braid Bias

THEMIS Instrument CDR 7 UCB, April 19-20, 2004 Preliminary PCB Layout

THEMIS Instrument CDR 8 UCB, April 19-20, 2004 BEB ETU

THEMIS Instrument CDR 9 UCB, April 19-20, 2004 BEB ETU

THEMIS Instrument CDR 10 UCB, April 19-20, 2004 BEB Parts Analysis Parts Stress Analysis Design meets derating guidelines of GSFC PPL-21 Worst Case Temperature Analysis Parts meet Temperature Guidelines –Operating Temperature range: –30C to 85C –Survival Temperature range: –50C to 125C Only one “high” power device (Actel 54SX72) –Operating power dissipation: 63 mW

THEMIS Instrument CDR 11 UCB, April 19-20, 2004 BEB ETU Mass and Power Power Estimated worst case power at PDR: 1667mW –Includes Preamp power of 324mW Measured ETU operating power: 790mW –Including Preamp, total = 1114mW Mass Estimated mass at PDR: 504g Measured ETU mass: 426g

THEMIS Instrument CDR 12 UCB, April 19-20, 2004 BEB ETU Test Results DC Response of Floating Ground Driver, FL_GND2

THEMIS Instrument CDR 13 UCB, April 19-20, 2004 BEB ETU Test Results (con’t) AC Response of Floating Ground Driver, FL_GND2

THEMIS Instrument CDR 14 UCB, April 19-20, 2004 BEB ETU Test Results (con’t) DC Response of Bias Driver, BIAS1

THEMIS Instrument CDR 15 UCB, April 19-20, 2004 BEB ETU Test Results (con’t) AC Response of Bias Driver, BIAS1

THEMIS Instrument CDR 16 UCB, April 19-20, 2004 BEB / EFI Subsystem Test Integrated Testing Includes: –BEB, Boom wire, Preamp –Sensor Boxes with Plasma Simulator (R║C) –GSE Automated Data Acquisition Test Results –DC Tests –Isolation, Sensor biasing, Usher/Guard Biasing, Braid biasing –DC Gain/Offset –AC Tests –AC input impedance, Transfer function, Crosstalk, Noise level –Linearity, Slew rate

THEMIS Instrument CDR 17 UCB, April 19-20, 2004 EFI Test/Characterization

THEMIS Instrument CDR 18 UCB, April 19-20, 2004 BEB GSE Data Acquisition Capabilities: Supports Automated test of Flight Hardware “VME-style” backplane –Accepts BEB and DFB –DCB-simulator implements CDI command 16-Channel 16-bit ADC (±100V range) –6 Vsphere, 2 Braid, 2 Usher, 2 Guard, 2 Flt. Gnd Programmable Signal Source w/ –±60Vdc offset range –30mV to 15Vpp AC (DC-16kHz) –1mV to 500mVpp AC (100k – 500kHz) LVPS and PCB simulation –Power services programmable on/off –+5VD, +2.5VD, ±10VA, ±100VA –Current monitors

THEMIS Instrument CDR 19 UCB, April 19-20, 2004 BEB GSE Data Acquisition

THEMIS Instrument CDR 20 UCB, April 19-20, 2004 BEB Design Status Completed ETU Design and Fabrication Characterization w.r.t. DC gain and AC response –In progress Available for testing with Preamp prototypes EFI Sensor Test Program GSE Data Acquisition system completed Integrated tests with preamps and boom units Issues Actel 54SX72 failures, total of 4 out of 7 –2 failed programming –2 failed “in circuit”, cause unknown TBD

THEMIS Instrument CDR 21 UCB, April 19-20, 2004 BEB Add’l Info Additional slides included: Floating ground driver schematic Bias driver schematic TBD

THEMIS Instrument CDR 22 UCB, April 19-20, 2004 Floating Ground Driver Heritage Design CLUSTER, POLAR, FAST Minor changes in part selection

THEMIS Instrument CDR 23 UCB, April 19-20, 2004 Bias Driver Heritage Design CLUSTER, POLAR, FAST Minor changes in parts selection and DAC