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Some thoughts on “ART2GBT” ASIC. Sorin Martoiu, IFIN-HH. De-serialize. Data formatting. Hit Selection. De-serialize. Hit Sel. Data formatting. De-serialize. Hit Sel. Data formatting. How fast the hit selection can be?. 1. (Asynchronous) Smart Token:. FLAG_IN. FLAG_IN. FLAG_IN.
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Some thoughts on “ART2GBT” ASIC Sorin Martoiu, IFIN-HH
De-serialize Data formatting Hit Selection
De-serialize Hit Sel Data formatting
De-serialize Hit Sel Data formatting
How fast the hit selection can be? 1. (Asynchronous) Smart Token: FLAG_IN FLAG_IN FLAG_IN Token stops when SUM = MAX_HIT_LIST FLAG_IN 2. Cascaded Priority Encoders: FLAGS_IN
How fast the hit selection can be? * MAX_HITS = 8 ** Very preliminary. 0.18 um tech MOSIS SCMOS (tsmc) (not IBM 0.13) / OSU FreePDK
How big the ASIC can be? • Full layout (fast attempt, not fully tested, …) • De-serializers • Hit selection • Data formatting (simple mux with pass- transistors) • (very) crude estimation: • 700 x 700 um2 • No triplication (x4) • 0.18 -> 0.13 (x 0.7) • tech, std. cells, pads…
How big the ASIC can be? • Number of I/O pads: • Inputs: 32 x 2 • Outputs: 40 x 2 • Total: 144 + pwr, clk, … • Options: • Reduce GBT i/f • 10 elinks@320MHz • Staggered pads • C4 ball bonds
5-bit Chip ID: max hits = 7 (80 bits = 7x11 + 3 spare) DOUT[39:0] A5 – 5+6 bits A12 – 5+6 bits BCID/ART A2 – 5+6 bits DOUT[79:40] empty empty BCID/ART A16 – 5+6 bits “000....00000” “000....00000” VMM 0, STRIP 0 ambiguity 32-bit Hit List: max hits = 8 (80 = 8x6 + 32) 32-bit hit list 12 2 5 16 DOUT[39:0] BCID/ART B.. DOUT[79:40] ART-6bits ..CID/ART ART-6bits ART-6bits ART-6bits empty
Preliminary Conclusions • Hit selection can be done in 0.5 BC, possibly even less (FPGA and ASIC) • Design fits well in low-range FPGAs (SPARTAN6 or ARTIX7 – probably valid for Altera devices too) • ASIC implementation looks feasible in <0.18um tech • Final chip area is governed by the number of pads/packaging solution • Power?
BCID transmission Cavern USA15 Fixed Latency GBT (TX) GBT (RX) TRIGGER PROC ART2GBT/VMM 3 1 2 3 1 2 BCID counter BCID counter TTC SYSTEM
8 hits 8 hits 4+4 hits 4+4 hits 2 of 4 traces partially lost 1 of 4 trace lost 2 of 8 trace lost Drift gap timing variation turned off…