PWI Meeting Kanazawa 25/03/2006

Active Measurement of Mercury’s Plasma, AM2P

CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUELaboratoire de Physique et Chimie de l'Environnement

3A, avenue de la Recherche ScientifiqueF-45071 Orléans cedex 02, France

Phone: (33 2) 38 25 52 63; Fax: (33 2) 38 63 12 34; E-mail: Jean-Gabriel.Trotignon@cnrs-orleans.fr

To Work, the AM²P Experiment Needs:

Sensors- MEFISTO E-field antenna → I/F

- Current probes

Analogue / sampling devices for acquisition- EWO electronics → I/F

Data processing / telecommands- MDP/DPU2 → I/F

Synthesizer- AM²P electronic board

PWI Meeting Kanazawa 25/03/2006

PWI Meeting Kanazawa 25/03/2006

PWI Meeting Kanazawa 25/03/2006

AM²P synthesizer (1)

Four different tasks :

1 – AM²P for impedance measurement → HF range

2 – MEFISTO for calibration and antenna lengths → LF and HF ranges

3 – WPT calibration → to be discussed

4 – SCDB calibration → LF range.

PWI Meeting Kanazawa 25/03/2006

AM²P synthesizer (2)

The synthesizer is synchronized by the 360 kHz EWO clock.

Two frequency ranges are delivered with a 512 ratio between them.

The HF range is used by AM²P to measure the MEFISTO HF impedance,

and for MEFISTO, and WPT (TBC) calibrations.

HF range Frequency band Δf

Band 1 (30 frequencies) 0.703 - 21.09 kHz 703 HzBand 2 (30 frequencies) 22.50 - 63.27 kHz 1.406 kHzBand 3 (30 frequencies) 66.08 - 147.63 kHz 2.812 kHz

LF range Frequency band Δf

Band 1 (30 frequencies) 1.37 - 41.19 Hz 1.37 HzBand 2 (30 frequencies) 43.94 - 123.6 Hz 2.75 HzBand 3 (30 frequencies) 129.07 - 288.34 Hz 5.49 Hz

The LF range is used for MEFISTO, SCDB and WPT (TBC) calibrations.

PWI Meeting Kanazawa 25/03/2006

Current Probe

PWI Meeting Kanazawa 25/03/2006

Interfaces (1)

Three main interfaces :

1 – With MEFISTO Connector MDM 25 pins (TBC).

2 – With EWO Connector MDM 25 pins (TBC).

3 – With MDP/PSU2 Connector MDM 9 pins.

PWI Meeting Kanazawa 25/03/2006

Interfaces (2)

PWI Meeting Kanazawa 25/03/2006

Interfaces (3)

2) Analogue interfaces with EWO connector MDM 25 pins.

2 current probes measurements sent on 2 differential lines (TBC),

- either CP1 on channel 1 and/or CP2 on channel 2,

- either CP1 on channel 2 and/or CP2 on channel 1,

- either CP1 and CP2 on the 2 differential inputs of channel 1 or channel 2 (complex mutual mode).

2 output channels from the AM²P synthesizer sent on 2 differential lines (TBC),

- 2 channels are used simultaneously for WPT calibration :

- first channel with phase 0,

- second channel with phase 90,

- the first channel is also used for SCDB calibration,

- these 2 channels are sent to EWO which is in charge to deliver them to the right instruments.

PWI Meeting Kanazawa 25/03/2006

Interfaces (4)

3) Digital interfaces with EWO 7 digital signals are exchanged on 7 differential LVDS lines.

From EWO to AM²P :

- 360 kHz clock to synchronize transmission with acquisition,

- transmission trigger to start a new sequence,

- serial 16 bits TC word,

- TC synchro which synchronizes the TC word sending,

From AM²P to EWO :

- TC acknow to acknowledge the correct reception of the TC word,

- acquisition trigger to start the storage of the first measurement point,

- transmission status which signals the periods where AM²P is transmitting.

AM²P

S/H1

S/H2

MUX ADC

MEM1

MEM2

360kHz

720kHz

CP

ME

FIS

TO

Sw

itche

s

Acquisition sync

Transmission sync

Transmission

Acquisition

PWI I/F Meeting Kanazawa 25/03/2006

PWI Meeting Kanazawa 25/03/2006

Interfaces (5)

4) With PSU2 Connector MDM 9 pins.

Pin allocation (TBC) :

- 1 chassis

- 2 – 3 +3.3 V

- 4 – 5 +5 V

- 6 – 9 COM2 (0 V)

- 7 +12 V

- 8 -12 V

PWI Meeting Kanazawa 25/03/2006

1) PCB size A5 format (210 x 148) refer to MDP document Part 2 Hardware (Sept. 2005).

2) Mass

- naked PCB A5 format : 114 g- varnish + screws + miscellaneous : 18 g- FPGA 25 g- sinus memory + DAC + amplifiers + switches 20 g

(only one synthesizer output channel)- other electronics 30 g- 3 MDM connectors 25 g- 2 current probes : 40 g

- sinus memory + DAC + amplifiers + switches : 20 g(second output channel for WPT calibration)

Total synthesizer 2 channels : 292 g

PWI Meeting Kanazawa 25/03/2006

Resources (1)

PWI Meeting Kanazawa 25/03/2006

Resources (2)

3) Power consumption (mW) Depending on modes.

The most part of analogue components are supplied with + & - 5 V to save power.

The -5 V is produced from -12 V by a voltage regulator.

When unused, the components are switched off (current probes, second synthesizer channel).

Supply voltages +3.3 V +5 V +12 V -12 V Total

Sphere modes and Basic mutual mode 198 56.5 6 166 426.5

Single wire mode 198 96.5 6 262 562.5

Double wire mode and Complex 198 136.5 6 358 698.5

mutual mode or antenna deployment

WPT calibration 231 113 6 326 676

PWI Meeting Kanazawa 25/03/2006

Planning – Manpower - Funding

AM²P planning to be updated according to the PWI planning.

Manpower :

- J.L. Michau TM

- F. Colin TM deputy – on-board S/W

- C. Cavoit current probe

- T. Hachemi electronics

- M. Lévêque A.Q.

- CDD EGSE + electronics.

Funding secured by CNES for 2006 – 2007, and then by a contract until launch.

PWI Meeting Kanazawa 25/03/2006

Pending questions

WPT calibration to be defined ASAP.

Interfaces with MEFISTO to be fixed ASAP.

AM²P measurement cycle is proposed to be about 1.5 s every 6 s : this period has to be fixed ASAP.

Possibility to skip data from the unused channel, in order to improve the AM²P performances on the used channel.

Data flow in low rate : about 0.04 kbs (modulus, phase,…).