2006/3/22 5-3-1

System Block Diagram

Mechanical Interface and Component Layout

Power Distribution

Major Subsystem Status

2006/3/22 5-3-2

System Block Diagram

DR

DMC

SSC

Normal Heater

SSAS-S×2

SASA

APR

: Signal

XDIP-A

XSW-A

XDIP-B

XSW-B

TWTA

TRP-A

TRP-B

XSW-C(DPDT

)

HGA

APM

RF S/STLM/CM

DRUADM

2ndPWR

ND

RJ

from/to ADM

SEPM/CPM/MPO

Power Source

MGA

from/to APM

MIA

MSA

MEA2

MEA1

HEP-i

HEP-e

ENA

MSASI

MDM

MGF-OMGF-IMAST-MGFPWI-SC MAST-SC

: RF

: SpaceWire DS link

: Primary Power

: PSU (other box)

CPM/MPOElectronics

SeparationConnector

XSW-C(DPDT

)

MDP-2 DPU PSU IPD

MGF-OMGF-I

PWI EWO SORBET AM2P MEFISTO-EMAST/WPT-E

PWI-WPT

PWI-MEFISTOTWTA

MDP-1 DPU PSU IPD

SpaceWire (A/B)

MIL-STD-1553B 　(A/B)

SEPM/CPM/MPO

Power Source

To UPG

To UPG

SSAS-E

SEPM/CPM/MPO

Power Source

Connector SeparationMechanism

Spin Ejection MechanismMechanism

CNV2

CNV1

SPM

RCS

P

thruster modulethruster module

valve module

P P

GN2TAN

K

BAT

PCU

IG-PS

PYRO forHGA LatchMechanism

Primary Powerfor S/S

S/S RTN

SW

&

Li

mit

er

BU

S-

BA

T

Sw

itch

: PSU (in the box)

Ｓｕｒｖｉｖａｌ Heater

From PCU

UPG

2006/3/22 5-3-3

Component Layout (1/2)

MIA

HEP-i

(1)

(4)

(5)

(2)

(3)

(6)

(7)

(8)

ENA

MEA2

Upper Thruster Module(2 places)

SSASMSA

MEA1 HEP-e

MAST-SC

MAST-MGF

X

Y

Z

MSASI

Lower Thruster Module(2 places)

MGA (after deployment)

WPT1

MAST-MGF

SSC

WPT2

MEFISTO2 MEFISTO1

MAST-SC

X

Y

Z

Top View Bottom View

2006/3/22 5-3-4

Component Layout (2/2)

Internal Surface of the Upper Deck,Perspective View from +Z direction.

THR-M

THR-M

Tank

Z X

Y

DRU

EPC

TWT

SSAS-E

SSAS-S

X-TRP1

XSW

XSW

XSW

XSW X-TRP2

TWTEPC

XDIP

XDIP

SPM

APR

DMC

Internal Surface of the Lower Deck,Perspective View from +Z direction.

CNV-1

CNV-2

Z X

Y

BAT

MDP1

MDP2

HEP-e

MEA

MAST-MGF

MAST-SC

HEP-i

MIA

MDM

V-M

MSAWPT-Pre

WPT-Pre

SSC

PCU

MSASIMEA

ENA

MDM-S

2006/3/22 5-3-5

Geometrical Interface for instruments

Updating now

Upper Deck

Bulkhead

Substrate Support Fixture

Lower Deck

Substrate

Substrate Support Fixture will be moved tothe exposed side.It will mitigate restriction on instruments mounting at the corner.

Ref. MMO-NT-D05013

2006/3/22 5-3-6

Power Distribution for payloads

Issues and possible resolutions

> Motors for MEFISTO, WPT, and MAST require 28V, not 50V. External PSU to provide 28V power

> Centralized vs. Distributed architecture.It would be too complex to have all of switching functions and secondary power supply functions at the MDP. External PSU for each MPPE and MDM instrument

> How to distribute +3.3V to instruments.It would be difficult to provide such a low voltage with good quality from the external PSU. To generate +3.3V by onboard regulator within instruments

2006/3/22 5-3-7

Alternative Power Distribution Architecture for payloads

PS

U

PS

U

PS

UM

EA

-1

PS

UM

EA

-2

PS

UM

IA

PS

UM

SA

PS

UH

EP

-e

PS

UH

EP

-i

PS

UEN

A

DP

U

MG

F-oe

MS

AS

I

PS

UM

DM

PW

IEW

O

MG

F-oe

PW

IS

OR

BE

TPW

IA

M2

P

PW

IM

EFIS

TO

-EM

AS

T/

WP

T-E

PS

U

PS

UD

PU

MDP-1

MD

P-2

IPD

PC

D

DM

C(A

)D

MC

(B)

DR

U(A

)D

RU

(B)

PC

D(A

)P

CD

(B)

XTR

P-A

XTR

P-B

EP

C-A

EP

C-B

10

lines

for

BU

S　

com

p.

PS

U

PS

U