SCM PREAMP & SENSORFabrication Readiness Review

P. Leroy

LPP Team

Co-I O. Le Contel, A. Roux

Technical Manager P. Leroy

Lead Engineer C. Coillot

Assistant Engineer D. Alison

QA Engineer L. Meslier (BTS Industrie) => 0.5 FTE

LPP/CNRS-Ecole Polytechnique PALAISEAU, FRANCE

SCM Team

Block Diagram

+X-X

-Y

+Y

RFxnpdr

1

23

4

5

67

8

PSEES

Battery

C&DH

StarSensors

Mag boom(stowed)

DPU

Mag boom(stowed)

S-Band Antenna

FEEPS

SCM Pre-Amp

Navigator

USO

DSS

SPACECRAFT DECKCOMPONENTS

S/C Location (1)

CEB EDI

EDI

SDP

SDP

SDP

SDP

ADP

AFG

DFG

SCM

AEB

INSTRUMENT DECKCOMPONENTS

(BOOMS DEPLOYED)

S/C Location (2)

SCM PREAMP

Low NoisePreamplifier46dB

Amplification& Filtering31.5dB

Feedback

B

CAL

VoutVin

From DSP

Scope: Design Overview• Sensor (3 one axis sensors in a triaxial structure)

– Primary coil– Secondary coil (feedback)

• Preamplifier (3 analog channels, Power Supply Regulation + Calibration Buffer)– 1st level of amplification: Low Noise + Feedback– 2nd level of amplification +filtering– Calibration in flight from DSP 33mm

30mm

18mm

MMS Preamp packaging

Action items since last review (CDR)

• Gains have been adjusted to meet the resolution requirement

• The preamp has been tuned with the EM4 sensors (4 mm ferrite cores). The sensitivity requirements are also satisfied now

• Radiation Qualification of the commercial JFET finished, LAT also. Screening end 16 OCT 2010

Screws (Stainless Steel)

Cover (Al 2024 T851)

Box (Al 7075 T7351)

• SCM Sensor harness routed through the Spacecraft Deck

• Connectors:– 15 pins DSub HD PCB mount (hard-

mounted before soldering)– 26 pins DSub HD crimp connector

• Surface treatments:– Alodine 1200– Black Anodization

• Right Angle Vent Hole Ø 2mm• FIELDS Preamp to Spacecraft

Mechanical/Thermal ICD (101600016)

Preamplifier Housing3D+ Hybrid Module

4 spacers added in the corners of the 3D+ Hybrid (Epoxy+EC2216) for vibration hardness

Ground lug connectionHole for Wire Thread Insert #8-32 x 1.5d

Fixtures

• MICD 10160 0016 C• Preamp interface: 4x Ø3.99 mm with the following pattern• Fasteners provided by the S/C team

3D+ Hybrid Workflow

Preamp Manufacturing Workflow

Parts status and 3D Module Manufacturing Flow

• Revision 3 of the Detail Specification Document from 3D+ (3DPA2800) released and signed

• All parts are in PIMS• Radiation memo written on the influence of total dose degradation and

single event transients on the RH1013 OP AMP• JFET Radiation test report released by LPP sub-contractor (qualification

successful)• 3 DPA done on all part references• Screening on the commercial parts (done prior to QM fabrication):

– done on the 2 capacitors AVX LD103C225KAB and AVX LD10YC475KAB– JFET 404 (done on LOT2 for the QM flow, we have another lot, LOT1, in house,

having passed LAT and Radiation Testing)• All other components are compliant with the ESA ESCC standard. No

additional screening planned.• 2 component kits for the QM manufacturing

– 1 QM deliverable– 1 backup kit

• 9 component kits for the FM manufacturing– 4 FM + 2 SM + 2 LAT deliverable– 1 backup kit

• Two lots of OP AMP RH1013, Lot 1: 67 parts, Lot 2: 20 parts (need 7 by 3D module).

JFET LS U404 Screening Issue

• Status after the screening of 40 parts:– 1 part rejected after mechanical inspection– 4 parts rejected after C-SAM inspection (Scanning Acoustic Microscopy)– 13/14 datasheet criteria met after Burn-In (160h/125°C) except CMR (Common Mode

Rejection)• Datasheet requirement is -95 dB or below for CMR • 3 parts OK, CMR < -95 dB (between -112 dB and -95.1dB)• 32 parts rejected, CMR > -95 dB (between -94.6 dB and -83 dB)• All parts have drifted

• CMR not measured during LAT and Radiation Testing– Gain, Noise, Power Consumption and Polarization are the relevant parameters for our

design, all were nominal and tested in SCM design configuration after LAT and Radiation Testing

– CMR could have an influence on the Power Supply Rejection Ratio (not sure)– No functional risk expected. Only risk = PSRR degradation (if any)

PREAMP Stage 1

Common Mode Rejection is not driving the design

B

Proposed Action Plan

Schedule

SCM SENSOR

Sensor Materials, Assembly Sequence and Processes

Raw Cores Characterization (LPP) => 1 Report File follows each sensor during the manufacturing flow (electrical tests, mass measurements, thermal cycling…)

Ferrite Cylinder (length=20cm) Ferrite 3C95 Ferroxcube

Machining (PRECINET)

Cores Characterization (LPP)

Winding (TECHNOPOINT)

Wire, 63μm (primary winding) Grade 1 (TECHNOPOINT)

Wire, 140μm (secondary winding) Grade H (TECHNOPOINT)

Kapton Tape (UNH)

Lacing Tape (TECHNOPOINT)

Copper Foil 30μm (electrostatic shielding)

Shielded Triplet Splicing and Soldering (TECHNOPOINT)

Shielded Triplet F A3901-2-3-28HG-B2 (3901-002-66-B2) Draka Fileca

Heat Shrinkable Sheath RNF100 RAYCHEM (TECHNOPOINT)

Sensor Materials, Assembly Sequence and Processes

Insertion in a PEEK Tube, Electrostatic Shielding Soldering (TECHNOPOINT)

PEEK Tube 450GL30 PMDK

Glue C2216

Windings Characterization (TECHNOPOINT+LPP)

X Ray Inspection (ANTICYP)

Potting (LPP)

Resin Mapsil 213-B MAP Silicones

Windings Characterization (TECHNOPOINT+LPP)

Mounting of the sensors in the structure

Triaxial structure PEEK 450CA30 STAE

PEEK Tube ClosedCoil insertion in PEEK tube

•SCM will be located at 4 m from the S/C and 1 m from AFG•Pigtail connector mounting on a bulkhead on the boom•Temperature measurement provided by a thermistor

Doc. James Sturm GSFCDoc. BTS Industrie, 046829 D ed00

SCM Adapter => Mag Boom ICD

•Positioning before fastening + sliding at the interface => 4 countersunk screws, in titanium TA6V (change since CDR: no more PEEK fasteners considered)•FIELDS SCM to Spacecraft Mechanical/Thermal ICD (10160 0025 B), 3D update needed, slight modifications due to the use of PEEK 450CA30

SCM Triaxial structure fastening

Changes since CDR

• Thermal Cycling on EM3 Sensor and X-Ray inspection reveal a weakness in the design

• Bepi Colombo sensors tested safely up to 200°C (and down to -180°C in June 2010)

• Ferrite core diameter smaller on MMS (3mm) than on Bepi Colombo (4mm) => Evolution for the QM, validated on EM4

– Increase in diameter of the ferrite core to strengthen the sensors (less risk during manufacturing)

– Negligible added mass, same overall dimensions• Material of the structure changed due to a problem of maturity

revealed during procurement of bars and blocks– PEEK 90HMF20 => PEEK 450CA30– Structure drawings updated

• Slight crack, very thin after the first thermal cycling of EM3

• Clearer after vibration at acceptance levels

Coils Manufacturing Workflow

Triaxial Sensor Manufacturing Workflow

Harness Parts

Composite Braided Shield 103-026-008S Glenair

Shielded Triplet F A3901-2-3-28HG-B2

3901-002-66-B2

Draka-Fileca

Twisted Shielded Pair F A3901-2-2-28HG-B2

3901-002-65-B2

Draka-Fileca

Connector Back-Shell

+ Adjustment Platen on the pigtail

DW 264-09-1-6-0021 Sommer

SubD HD Connector 15P 3401 002 02B DEMA 15P NMB FO C&K

SubD HD Connector 15S 3401 002 02B DEMA 15S NMB FO C&K

SubD HD Male Contacts 3401 005 07B C&K

SubD HD Female Contacts 3401 005 08B C&K

SCM Connector Bracket

Harness Manufacturing Workflow

Schedule

QA Activites, Qualification, Calibration

QA Activities Status

• Done– Configuration under control (Excel Configuration File)– SCM dedicated project documentation (all forms)– Manufacturers & suppliers defined– Manufacturing flowchart with all KIP/MIP (Mandatory/Key Inspection Points)

• To be done– AIT documented (logbook filling…)

• QM/FM fully under configuration:– 100% of our Items are identified by a drawing or a product ref.– Etching will be done at strategic locations on the main parts– Specific quantity is forecast for each model– Item Batch will be recorded in the configuration if any.– Materials & surface treatments controlled – Certificates of conformance will be provided– NCR, ECR, RFW/D will be followed in terms of each item

• FM will be built as QM (including QM NCR preventive & corrective actions)

SCM Configuration File

AIT Logbook

Env Testing & Qual Workflow

Resources

ResourcesSpecial Operations LPP LPP Alternate Subcontractor

    SCM Electrical Subsystems          Preamplifier          3D Hybrid Fabrication     3D+

   PWB Fabrication, PWB Populating (3D Hybrid, Connectors), Integration in Housing     STEEL Electronique

    Sensor          Windings     Technopoint    Electrostatic Shielding Soldering and Integration in PEEK Tubes DAL, PLE CCO Technopoint    Pigtail Connexion DAL, LME YSI IAS    Harness     IAS    Preamplifier + Sensor          GSE DAL YSI      Overall Calibration PLE CCO      SCM Mechanical Subsystems          Preamplifier Housing          Preamplifier Housing Manufacturing     BTS Industrie    Sensor          Ferrite Cores Machining     Optik-C    PEEK Tubes Machining     MPC    Triaxial Structure Machining     STAE    PEEK Fasteners Machining     BTS Industrie    Potting, Triaxis Assembly PLE CCO         LPP SCM Regular TEAM    PLE = Paul Leroy (Research Engineer, permanent position)    DAL = Dominique Alison (Assistant Engineer, permanent position)    LME = Lionel Meslier (QA Engineer, BTS Industrie, 0,5 FTE)    LPP Alternate Sources    CCO = Christophe Coillot (Research Engineer, permanent position)

   YSI = Yannick Simon (Study Engineer, temporary position Sep 2010-Dec 2011)

SCM PREAMP & SENSORFabrication Readiness Review

P. Leroy