MAX3945/46: Low-jitter, integrated 10Gbps chipset enables < 1W SFP+ modules with mask margin to spare

The combined power consumption of the MAX3946 and MAX3945 is only 355mW, leaving plenty of margin for the optical subsystem and control. Both ICs include a 3-wire digital control interface with integrated control DACs to reduce external component count. Outstanding jitter performance eases design tolerances and improves manufacturing yield in SFP+ optical transceivers. This chipset is optimized for Ethernet and Fibre Channel transmission systems at data rates up to 11.3Gbps.

The MAX3946 is a 3.3V, multirate laser diode driver that is optimized to drive a differential transmitter optical subassembly (TOSA) with a 25ohm flex circuit up to 100mA modulation current and up to 80mA bias current. The unique design of the output stage enables the use of unmatched TOSAs to reduce headroom limitations and lower module power consumption by 100mW, with only 5psP-P deterministic jitter.

The MAX3945 is a 3.3V, multirate, high-sensitivity limiting amplifier that limits the signal generated by a transimpedance amplifier into a CML-level differential output signal. The dual-path limiting amplifier's programmable filter optimizes sensitivity for different data rates and suppresses relaxation oscillations that could occur in legacy optical systems.