I7070 general description the I7070 is a +3.3v/5v laser diode driver for sfp/ sff applications up to 1.25gbps. the device accepts differential input dat a and provides bias and modulation currents for driving a laser. dc-couplin g laser to the device eases of multi rate applications and reduces the external componen t count. the I7070 is fully compliant with the sfp msa timing and the sff- 8472 transmit diagnostic requirements. an automatic power control (apc) feedback loop is i ncorporated to maintain a constant average optical power over temperature and lifetime. optional temperature compensation compensates laser diode extinction rat io change with temperature over 500ppm ~ 10,000ppm range. the wide modulation curre nt range of 5ma to 85ma and bias current of 1ma to 100ma make this product ideal for driving fp/dfb laser diodes in fiber optic modules. the I7070 also provides transmit-disable control (d isable), a single-point latched transmit-failure monitor output (fault), ph otocurrent monitoring, and bias-current monitoring to indicate faults, such as when the apc loop is unable to maintain the average optical power. the I7070 comes in a 4mm * 4mm 24-pin qfn package a nd operates over the extended temperature range of -40 c to +85 c. features ? single +3.3v or +5v power supply ? automatic average power control ( apc ) ? fully compliant with sfp and sff-8472 msas ? programmable modulation current from 5ma to 60ma (d c-coupled) ? programmable modulation current from 5ma to 85ma (a c-coupled) ? programmable temperature compensation ? programmable bias current from 1ma to 100ma ? bias and modulation current monitor ? edge transition time < 130ps ? 51ma typical power-supply current ? multirate 155mbps to 1.25gbps operation ? 24-pin 4mm * 4mm qfn package
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