A content addressable memory for use in CEBAF`s CLAS detector level 2 triggering system

Journal Article · Sat Jun 01 04:00:00 EDT 1996 · IEEE Transactions on Nuclear Science

DOI:https://doi.org/10.1109/23.507169· OSTI ID:276479

Hodson, R F; Doughty, Jr, D C; Allgood, D C; Campbell, S A ^[1]; Wilson, W C ^[2]; Bickley, M H ^[3]

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1. Christopher Newport Univ., Newport News, VA (United States)
2. NASA Langley Research Center, Hampton, VA (United States)
3. CEBAF, Newport News, VA (United States)

A collaboration of researchers from CEBAF, CNU and NASA is designing a 256 x 32 specialized Content Addressable Memory (CAM) for the level 2 triggering system in CEBAF`s CLAS detector. These integrated circuits will find tracks and the momentum and angle of each track within 2 microseconds of an event. The custom CAM can operate as conventional memory, performing read and write operations, and can additionally perform independent byte compare operations across all words simultaneously. It is this compare feature which makes these CAMs attractive for identifying tracks passing through drift chambers by linking together segment number triplets within the CAM. Simulations have indicated that less than 16k triplets need to be stored for each sector of the detector. This implies the level 2 triggering can be performed with 64 CAM chips per sector, or 384 total. Each data channel into a sector CAM array is buffered in a FIFO and is designed to handle aggregate data rates up to 750 Mbs for three channels (one channel/superlayer). The architecture of the level 2 trigger and details of the CAM chip design are discussed along with a performance report on the prototype CAMs.

• OSTI ID: 276479
• Report Number(s): CONF-951073--
• Journal Information: IEEE Transactions on Nuclear Science, Journal Name: IEEE Transactions on Nuclear Science Journal Issue: 3Pt2 Vol. 43; ISSN 0018-9499; ISSN IETNAE
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
CEBAF ACCELERATOR
DATA ACQUISITION SYSTEMS
DESIGN
MEMORY DEVICES
PARTICLE TRACKS
PERFORMANCE
RADIATION DETECTORS
TRIGGER CIRCUITS