HOLA
High-speed Optical Link for Atlas

2.5 Gbps S-LINK LSC and LDC S-LINK Interface

(Circuit number EP680-1169-250)
Link Source Card bottom view (top view).

DESCRIPTION

The HOLA S-LINK interface is a standard S-LINK implementation which uses the TI TLK2501 2.5 Gbps transceiver both for the forward and for the return channel (one per card). For the optical transmission Small Form Factor Pluggable (SFP) Multimode transceivers with LC Connector are used. As opposed to the ODIN S-LINK, the HOLA can transfer data at the full S-LINK bandwidth of 160 MB/s with only one duplex fiber. Furthermore the HOLA is less expensive than the ODIN.

The design is not intended to be used in an environment with radiation.

General features

Duplex S-LINK
32-bit data width
UCLK up to 40 MHz
125 MHz link clock
160 MBytes/s maximum data rate
125 MBytes/s transmission rate for control information (UCTRL# low)
31.25 MHz sampling rate for the return lines
Block basis error reporting on data words
Word-by-word error reporting on control words
3.3V supply voltage
Autonomous link synchronization and maintenance of physical link
Improved S-LINK Reset protocol
Test function for the return lines
Flow control is provided both in data mode and self test modes
only one duplex fiber needed for full S-LINK bandwidth of 160 MB/s
User replaceable Small From-factor Pluggable fiber-optic transceiver

STATUS

10 October 2001	Hardware specification ready
1 March 2002	Schematics ready and reviewed by Peter Jansweijer/NIKHEF and Tivadar Kiss/CERNTECH. PCB design will start 7 March
11 April 2002	PCB design finished. 16 boards ordered (5 prototype links and 6 empty PCBs for NIKHEF MDT)
24 April 2002	Empty PCBs will arrive 20 May (delays in ordering because of holidays and miscommunication)
15 May 2002	18 empty PCBs arrived
28 May 2002	6 boards mounted. Found problem with pad stack TLK2501 (IC smaller than pads). No problem for debugging, but needs re-layout for series production.
30 June 2002	One full link debugged and completely working. Aurelio Ruiz, designer of the card, left CERN. Aurelio has won a digital camera with the EBV design contest.
1 July 2002	Jesper Haee will do a full verification and review of the design
11 October 2002	PCB design improved. Review of design finished.
15 January 2003	CERNTECH is producing a first batch of 30 HOLA cards, the modules are expected in February.