Finisar AN-2030 specifications N i s a r

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AN-2030: Digital Diagnostic Monitoring Interface for Optical Transceivers

F i n i s a r

1External Calibration

2Measurements are raw A/D values and must be converted to real units using calibration

3constants stored in EEPROM locations 56 – 95 at 2 wire serial bus address A2h (see

4 Table 3.15). Calibration is valid over specified device operating temperature and

5voltage. Alarm and warning threshold values should be interpreted in the same manner

6as real time 16 bit data.

71) Internally measured transceiver temperature. Module temperature, T, is given by the

8following equation: T(C) = Tslope * TAD (16 bit signed twos complement value) + Toffset.

9The result is in units of 1/256C, yielding a total range of –128C to +128C. See Table

103.15 for locations of TSLOPE and TOFFSET. Temperature measurement is valid from –

1140°C to +125°C with an accuracy of ± 3°C. The temperature sensor is located in the

12center of the module and is typically 5 to 10 degrees hotter than the module case. See

13Tables 3.12 and 3.13 above for examples of temperature format.

142) Internally measured transceiver supply voltage. Module internal supply voltage, V, is

15given in microvolts by the following equation: V(µV) = VSLOPE * VAD (16 bit unsigned

16integer) + VOFFSET . The result is in units of 100µV, yielding a total range of 0 – 6.55V.

17See Table 3.15 for locations of VSLOPE and VOFFSET . Accuracy is ±100mV.

183) Measured transmitter laser bias current. Module laser bias current, I, is given by the

19following equation: I(µA) = ISLOPE * IAD (16 bit unsigned integer) + IOFFSET . This result is

20in units of 2 µA, yielding a total range of 0 to 131 mA. See Table 3.15 for locations of

21ISLOPE and IOFFSET. Accuracy is ± 10%. Early versions of the digital diagnostic standard

22(SFF-8472) used a scale factor of 1µA/AD Count for interpreting laser bias current

23readings. SFF-8472 later changed the scale factor to the current value of 2µA/AD

24Count. All Finisar modules using a scale factor of 2µA/AD Count have an ASCII “A”

25written in byte 56 of the ‘vendor rev’ field (see table 3.1). Legacy Finisar modules using

26a scale factor of 1µA/AD Count contain either zero or ASCII space (20h) or one of two

27place holders: “X1—“, “1A—“, in location 56.

284) Measured coupled TX output power. Module transmitter coupled output power,

29TX_PWR, is given in µW by the following equation: TX_PWR (µW) = TX_PWRSLOPE *

30TX_PWRAD (16 bit unsigned integer) + TX_PWROFFSET. This result is in units of 0.1µW

31yielding a total range of 0 – 6.5mW. See Table 3.15 for locations of TX_PWRSLOPE and

32 TX_PWROFFSET. Data is factory calibrated to absolute units using the most

33representative fiber output type. Accuracy is ±3dB. Data is not valid when the

34transmitter is disabled.

35

9/26/02 Revision D

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Contents 35 2. Applicable Documents Scope and OverviewEnhanced Digital Diagnostic Interface Definition Overview Control Functions 8 bytes Password Entry 8 bytesSpecific Data Field Descriptions Cal Constants BytesData Serial ID Data Fields Address A0Name Bytes Description of Field Address Extended Identifier ConnectorIdentifier Identifier valuesDescription of connector Connector valuesTransceiver codes TransceiverCode Description of encoding mechanism 4a Sonet Reach SpecifiersEncoding Speed Reach Specifier bit DescriptionLength 50μ BR, nominalLength 9μ-km Length 9μVendor OUI Length CopperVendor name Dwdm Channel SpacingLaser Wavelength Vendor RevDwdm Wavelength Fraction 13 BR, min OptionsOption values BR, maxDate Code Diagnostic Monitoring TypeData Description of field Address N i s a r Enhanced Options SFF-8472 Compliance 10 I/O Timing for Soft Control & Status Functions11 SFF-8472 Compliance Diagnostics 13 Digital temperature format Temperature 12 Bit weights C for temperature reporting registersN i s a r 14 Alarm and Warning Thresholds 2-Wire Address A2h Alarm and Warning ThresholdsN i s a r 16b Format for offsets 16a Unsigned fixed-point binary format for slopes16d Example of Floating Point Representation 16c IEEE-754 Single-Precision Floating Point Number FormatBit Name Description LOS Alarm and Warning Flags18 Alarm and Warning Flag Bits 2-Wire Address A2h Address # Bytes Name Description 19 Password Addresses 2-Wire Address A2h20 User Eeprom 2-Wire Address A2h Byte Bit Name DescriptionDdtc Electrical Interface Definition Overview Wire Interface OperationN i s a r Current Address Read Detailed 2 -Wire Serial Port Operation N i s a r Wire Protocol Data Transfer Protocol Vcc = 3.15V to DC Electrical CharacteristicsFor More Information
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