SY88903AL 3.3V, Burst Mode 1.25Gbps PECL High- Sensitivity Limiting Post Amplifier with TTL Loss-of-Signal General Description Features The SY88903AL, burst mode, high-sensitivity limiting Single 3.3V power supply post amplifier is designed for use in fiber-optic receivers, Fast LOS release/assert (<500ns) time for PON specially optimized for passive optical networks (PONs). applications The device connects to typical transimpedance 622Mbps to 1.25Gbps operation amplifiers (TIAs). The linear signal output from TIAs can Low-noise PECL data outputs contain significant amounts of noise and may vary in amplitude over time. The SY88903AL quantizes these High gain LOS signals and outputs PECL level waveforms. Chatter-free Open-Collector TTL signal detect (LOS) The SY88903AL operates from a single +3.3V power output with internal 4.75k pull-up resistor o o supply, over temperatures ranging from 40 C to +85 C. TTL /EN input Signals with data rates from 622Mbps up to 1.25Gbps, Programmable LOS level set (LOS ) LVL and as small as 5mV , can be amplified to drive pp Available in a tiny 10-pin MSOP package devices with PECL inputs. The SY88903AL generates a Loss-of-Signal (LOS) Applications open-collector TTL output. A programmable Loss-of- GPON/GEPON/EPON Signal level set pin (LOS ) sets the sensitivity of the LVL input amplitude detection. LOS asserts high if the input Gigabit Ethernet, 1062Mbps Fibre Channel amplitude falls below the threshold set by LOS and LVL OC-12/24 SONET/SDH de-asserts low otherwise. The enable bar input (/EN) Low-gain TIA interface de-asserts the true output signal without removing the High-gain line driver and line receiver input signal. The LOS output can be fed back to the /EN input to maintain output stability under a loss-of-signal Markets condition. Typically, 3.4dB LOS hysteresis is provided to prevent chattering. FTTH/FTTP All support documentation can be found on Micrels web Datacom/telecom site at: www.micrel.com. Optical transceiver 1 M9999-021707-D February 2007 hbwhelp micrel.com or (408) 955-1690 Micrel, Inc. SY88903AL Typical Application Circuit 2 M9999-021707-D February 2007 hbwhelp micrel.com or (408) 955-1690