SY88903KC

Overview

The SY88903KC is a high-speed limiting post amplifier designed for fiber-optic receivers operating at data rates up to 1.25Gbps. It features differential PECL inputs and outputs, with an open-collector TTL Loss of Signal (LOS) output. The device amplifies input signals as small as 5mVp-p and incorporates a programmable level detect function via the LOSLVL pin to identify signal loss. It operates on a single power supply within the commercial temperature range of -40°C to +85°C.

Feature Summary

• Provides high gain and wide bandwidth for amplifying low-level signals in fiber-optic applications
• Generates a chatter-free Loss of Signal indicator using a TTL open collector output
• Features a programmable level detect function to maintain stability under signal loss conditions
• Accepts differential PECL data inputs and provides corresponding PECL outputs

Applications

• 1.25Gbps Gigabit Ethernet
• 531Mbps and 1062Mbps Fibre Channel
• 622Mbps SONET
• Gigabit Interface Converter

Procurement Notes

Verify that the component matches the specific K10-1 package type and Sn-Pb lead finish indicated by the KC suffix. Confirm the manufacturer origin, as the part was originally produced by Micrel, Inc., prior to acquisition. Ensure the design accounts for the commercial temperature rating (-40°C to +85°C). Check for any updated documentation regarding the discontinuation status or recommended alternatives.

Selection Notes

Select this component when a limiting post amplifier is required for fiber-optic links up to 1.25Gbps. It is suitable for interfacing with transimpedance amplifiers where noise quantization is necessary. Consider the need for a TTL-compatible LOS output and the ability to adjust sensitivity via an external resistor divider. Verify compatibility with the system's PECL signaling requirements and power supply constraints.

Part Context

The SY88903KC belongs to the SY88903 series of limiting post amplifiers manufactured by Micrel, now part of Microchip Technology. This series is specifically engineered for high-frequency fiber-optic applications, providing signal conditioning between the optical receiver front-end and subsequent digital processing stages. The KC designation identifies the specific MSOP-10 package variant with commercial temperature ratings.

Replacement Considerations

Public confirmed substitute part numbers: SY88903KCTR, SY88903KH, SY88903KHTR.