3.3 V 2.7 Gb/s Limiting Amplifier

The ADN2890 is a high gain, limiting amplifier optimized for use in SONET, Gigabit Ethernet (GbE), and Fibre Channel optical receivers that accept input levels of up to 2.0 V p-p differential and have 3 mV p-p differential input sensitivity. The ADN2890 provides the receiver functions of quantization and loss of signal (LOS) detection. The ADN2890 can easily operate at up to 3.2 Gb/s to support LX4 transceivers.

The limiting amplifier also measures average received power based on a direct measurement of the photodiode current with better than 1 dB of accuracy over the entire input range of the receiver. This eliminates the need for external average Rx power detection circuitry in SFF-8472 compliant optical transceivers.

The ADN2890 limiting amplifier operates from a single 3.3 V supply, has low power dissipation, and is available in a space-saving 3 mm × 3 mm 16-lead lead frame chip scale package (LFCSP).

Applications

* SFP/SFF/GBIC optical transceivers

* OC-3/12/48, GbE, Fibre Channel receivers

* 10GBASE-LX4 transceivers

* WDM transponders

* SFP reference design available

* Input sensitivity: 3 mV p-p

* 80 ps rise/fall times

* CML outputs: 700 mV p-p differential

* Programmable LOS detector: 2 mV to 13 mV

* Rx signal strength indicator (RSSI):

* SFF-8472 compliant average power measurement

* Single-supply operation: 3.3 V

* Low power dissipation: 130 mW

* Available in space-saving 3 mm × 3 mm 16-lead LFCSP