Optical Readout Interface (ORI) latency +24 ns +24 ns +300 ns Conf. Mem. 125MHz 120MHz 8 bit DDR I2C SERDES 2.5GBits/s Laser Driver CPLD HCM (TRAP) LVDS-TTL 16 DDR SDR Resynchronization, status, counters VCSEL Laser Diode 850 nm

ORI – production test (laser diode) Several parameters controlled: Supply currents at various operation mode conditions Voltages on the board in enabled/disabled state Source, bias and modulation currents through the laser diode Temperature of the laser driver chip optical output power photodiode current measured by the laser driver chip

No permanently damaged components. Equivalent time in years in blue, No permanently damaged components. Equivalent time in years in blue, * - the device fails. Recovery after power cycle or switching off for up to 12 hours (VR and Laser Driver). The configuration of the CPLD and EEPROM was not damaged. Laser Driver Linear Technology LTC5100 100* VCSEL Diode ULM Photonics ULM850-02-LC-TOSA 20 EEPROM 24LC01 30* LVDS Transceiver National Semiconductor DS90LV048A 30 CPLD Lattice LC4256V 15-50* Serializer Texas Instruments TLK2501 250* Voltage Regulators National Semicondutor LP3962-3.3 and -2.5 60-110* F.Rettig

CLK C D Q Q A Y0 Y1 Y2 Y3 E D Q GCNTp decoder 4:1 mux with gray encoding GCNTc STROBE IN DATA GREG B A=B comp Falling edge data OUT DATA VALID