Radiation Testing of MDT Front-End Components

Mezz card rad summary • Brief summary with links to backup documents &bull 25 July 2007

"Simulated Radiation Levels and Current Test Status for ATLAS MDT Front-End Electronics" note from April 2003, with detailed, board-by-board analysis of radiation levels.

We must tested all components of the front-end electronics to meet the ATLAS Policy. The radiation levels are specified in the MDT PDR Report of 22 Feb 2001. This page will document the testing of the voltage regulators and LVDS drivers/receivers on the mezzanine PCB. Other active components which are being tested elsewhere include the MDT-ASD chip (Christoph Posch at CERN) and the AMT-2 chip (Yasuo Arai at KEK).

Temperature Sensors

• TMP36/37 temperature sensors were tested to 300kRad in a proton beam. The results are summarized in this report.

Voltage Regulators

Single-Event Effects

We have tested 10 devices of each of 3 types at the Harvard Cyclotron, which produces 165 MeV protons in a roughly 1 inch diameter beam. We have built two test boards: one which holds 6 voltage regulators plus load resistors and capacitors, and a DAQ board with ADCs, window comparators, and counters to monitor the regulator outputs.

The devices we have tested are:

• Texas Instruments TPS7333QD
• Burr-Brown/T.I. REG103GAPW
• National LP3964EMP-3.3

The basic test strategy was to operate the regulator under load conditions similar to those in normal operation, and to monitor the regulator output for voltage changes and transients. The regulator input current was also monitored. The power was cycled off and on periodically during testing as necessary to clear any latch-up conditions.

Results: No single-event effects were seen. Most devices failed eventually due to apparently cumulative effects of either total ionizing dose or accompanying neutrons.

SEE Test Results
Device	No Devices Tested	SEE Seen	Total protons/cm^2
TPS7333	10	0	1.1E13
LP3964	10	0	1.1E13
REG103	10	0	3.2E12

Preliminary TID Test Results
Device	Number of Devices Tested	Failure Dose (Gy/kRad)
TPS7333	10	450/45
LP3964	10	600/60
REG103	10	210/21


Here is a plot: all3.pdf of the output voltage vs total ionizing dose.
Here are the Atlas Test Reports: Cyclotron21Jul01.zip"

Total Ionizing Dose (TID)

We have built a test board to hold 10 each of the 3 types tailored to the geometry of the Co(60) source at Brookhaven, and plan to do a TID test in January 2002.

Non-Ionizing Energy Loss (Neutron)

We irradiated samples of each of the 3 types at the Prospero facility in October, 2001. As of now (Dec 2001) we are awaiting the return of the irradiated devices to test them.

LVDS Driver/Receiver

ATLAS Links

Muon RPC Radiation Assurance

Other Sources of Radiation Test Data

ESA Radiation Effects page

NASA Goddard Radiation Test Data
Radiation Effects page

NASA JPL Radiation Effects Database

ERRIC (Electronics Radiation Response Information Center) Main page