General Description The MIC3000 enables the implementation of sophisticated, hot-pluggable fiber optic transceivers with intelligent laser control and Digital Diagnostic Monitoring Interface per SFF-8472. It essentially integrates all non-datapath functions of an SFP transceiver into a tiny 4mm x 4mm MLF® package. It also works well as a microcontroller peripheral in transponders or 10Gbps transceivers. A highly configurable automatic power control (APC) circuit controls laser bias. Bias and modulation are temperature compensated using dual DACs, an on-chip temperature sensor, and NVRAM look-up tables. A programmable internal feedback resistor provides unprecedented dynamic range for APC. Controlled laser turn-on facilitates hot-plugging. An analog-to-digital converter converts the measured temperature, voltage, bias current, transmit power, and received power from analog-to-digital. Each parameter is compared against user-programmed warning and alarm thresholds. Analog comparators and DACs provide high-speed monitoring of received power and critical laser operating parameters. An interrupt output, power-on hour meter, and data-ready bits add user friendliness beyond SFF-8472. The interrupt output and data-ready bits reduce overhead in the host system. The power-on hour meter logs operating hours using an internal real-time clock and stores the result in NVRAM. Communication with the MIC3000 is via an industry standard 2-wire serial interface. Nonvolatile memory is provided for serial ID, configuration, and separate OEM and user scratchpad spaces. Two-level password protection guards against data corruption. Features • APC or constant-current laser bias • Supports multiple laser types and bias circuit topologies • Drives external low-cost BJT for laser bias • Integrated digital temperature sensor • Temperature compensation of modulation, bias, and fault levels via NVRAM look-up tables • Direct interface to SY88932, SY88982, SY89307 and other drivers • NVRAM to support GBIC/SFP serial ID function • User writable EEPROM scratchpad • Diagnostic monitoring interface per SFF-8472 – Monitors and reports critical parameters: temperature, bias current, TX and RX optical power, and supply voltage – S/W control and monitoring of TXFAULT, RXLOS, RATESELECT, and TXDISABLE – External calibration • Power-on hour meter • Interrupt capability • Extensive test and calibration features • 2-wire I2C compatible serial interface • SFP MSA and SFF-8472 compliant • 3.0V to 3.6V power supply range • 5V-tolerant I/O • 4mm x 4mm 24-pin MLF® package Applications • SFF/SFP optical transceivers • SONET/SDH transceivers and transponders • Fibre channel transceivers • 10Gbps transceivers • Free space optical communications • Proprietary optical links
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