The MAX3748/MAX3748A multirate limiting amplifier functions as a data quantizer for SONET, Fibre Channel, and Gigabit Ethernet optical receivers. The amplifier accepts a wide range of input voltages and provides constant-level current-mode logic (CML) output voltages with controlled edge speeds. A received-signal-strength indicator (RSSI) is available when the MAX3748/MAX3748A is combined with the MAX3744 SFP transimpedance amplifier (TIA).