The MEX is dedicated to the study of radiation effects of space environment on electronic components. The effects targeted are Total Ionizing Dose, Single Event Effects and Displacement Damage. Various test vehicles (DUTs) have been chosen upon a list of very sensitive devices identified when performing ground testing (Memories, linear and optoelectronics devices, power MOSFETs, etc.).
The MEX is made of an analogue part and a logic one managed through a FPGA and its buffer memory. The analogue part is made of measurement circuits connected to the FPGA via ADCs and DACs. It controls the dosimetry and TID sections and part of the SEE section. The logic part is made of two blocks dedicated to SEU detection.
The figure below shows the MEX engineering model and its packaging. The MEX is located at the bottom of the ICARE-NG instrument. Its packaging is used to fix the complete ICARE-NG instrument on the wall of the satellites (internal side). In this way, the MEX test board is the most exposed to radiation coming from the outside of the satellite.
The EXPERIENCE Module can be changed easily from one mission to another. The EXPERIENCE Module can be switched off independently from the ICARE-NG SPECTROMETER unit.
On-board dosimeters are used to measure precisely the ionizing dose constraint encountered by CARMEN experiments. Two kinds of dosimeters are used on MEX: two RADFET dosimeters from TRAD and one OSL (Optically Stimulated Luminescence) dosimeter developed by the IES laboratory at the University of Montpellier II. All are placed in the same area in order to provide comparable data set.
RADFET Dosimeter from TRAD
OSL Dosimeter from IES Montpellier II University
DUTs on board different CARMEN missions with the associated radiation effect are listed in the table below:
|DUT References||Function||Number of DUT/MEX||Effect||CARMEN Missions|
|HITACHI HM628512C||SRAM 512k x 8 bits||2||SEU||1, 2|
|BSI BS616LV1611TI||SRAM 1M x 16 bits||1||SEU||3, 4|
|SAMSUNG KM6840000A||SRAM 512k x 8 bits||2||SEU||1, 2|
|CYPRESS CY62167EV30||SRAM 1M x 16 bits||1||SEU||3, 4|
|3D+ MMSR32001608S-C||SRAM 2M x 16 bits||1||SEU||1, 2|
|3D+ 3DSR32M32VS8504||SRAM 32M x 32 bits||1||SEU||3, 4|
|SAMSUNG K7A81800M 6||SSRAM 512k x 16 bits||1||SEU||1, 2, 3, 4|
|IDT IDT71V3558S133PSI||SSRAM 256k x 16 bits||1||SEU||1, 2, 3, 4|
|INFINEON HYB39S512800AT||SDRAM 64M x 8 bits||2||SEU||1, 2, 3, 4|
|MICRON MT48LC64M8A2||SDRAM 64M x 8 bits||2||SEU||1, 2, 3, 4|
|3D+ MMSD08512408S-Y SDRAM||SDRAM 512M x 8 bits||2||SEU||1, 2|
|3D+ 3DSD4G08VS8184||SDRAM 512M x 8 bits||2||SEU||3, 4|
|SAMSUNG K4S560432C SDRAM||SDRAM 64M x 4 bits||2||SEU||1, 2, 3, 4|
|SAMSUNG KM44V16004B||DDRAM 16M x 4 bits||2||SEU||1, 2|
|CYPRESS CY7C1069 SRAM||SRAM 2M x 8 bits||1||SEL||1, 2, 3, 4|
|BSI BS616LV1611TI||SRAM 1M x 16 bits||1||SEL||3, 4|
|INTERNATIONAL RECTIFIER IRF360 400V||N-channel power MOSFET||4||SEB||1, 2, 3, 4|
|NATIONAL SEMICONDUCTORS LM324||Operational amplifier||1||SET||1, 2, 3, 4|
|NATIONAL SEMICONDUCTORS LM139||Voltage comparator||1||SET||1, 2|
|ANALOGUE DEVICES OP470||Operational amplifier||1||SET/SEDR||1, 2, 3, 4|
|MAXIM MAX663E||Dual Mode Regulator||1||TID||1, 2, 3, 4|
|MAXIM MAX664E||Dual Mode Regulator||1||TID||1, 2, 3, 4|
|OSRAM BPW34F||Photodiode||1||DDD||1, 2, 3, 4|
|IES OSL||Dosimeter||1||TID/DDD||1, 2, 3, 4|
|TRAD Space Dosimeter||Dosimeter||2||TID||1, 2, 3, 4|