Maxim 1.0625 to 11.3 Gbps transmit/receive chipset

Maxim has introduced a 1.0625 to 11.3 Gbps transmit/receive solution composed of the MAX3946 laser driver with impedance-mismatch tolerance and the MAX3945 dual-path limiting amplifier.

This 10GBASE-SR/LR SFP+ transmit/receive chipset enables <1 W SFP+ optical modules while reducing overall module cost. The combined power consumption is 355 mW. Both ICs include a 3-wire digital control interface with integrated control DACs to reduce external component count. The chipset is optimised for ethernet and fibre-channel transmission systems at data rates up to 11.3 Gbps.

The 3946 is a 3.3 V, multirate laser diode driver, optimised to drive a differential transmitter optical subassembly with a 25 Ω flex circuit up to 100 mA modulation current and up to 80 mA bias current.

The design of the output stage enables the use of unmatched TOSAs to reduce headroom limitations and lower module power consumption by 100 mW, with only 5 psP-P deterministic jitter.

The 3945 is a 3.3 V, multirate, high-sensitivity 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 optimises sensitivity for different data rates and suppresses relaxation oscillations that could occur in legacy optical systems.