ADN2891 Datasheet | Analog Devices

FEATURES Input sensitivity: 4 m V p-p 80 ps rise/fall times CML outputs: 700 m V p-p differential Programmable LOS detector: 3.5 m V to 35 m V Rx signal strength indicator (RSSI) SFF-8472-pliant average power measurement Single-supply operation: 3.3 V Low power dissipation: 145 m W Available in space-saving 3 mm × 3 mm, 16-lead LFCSP Extended temperature range: - 40°C to +95°C SFP reference design available GENERAL DESCRIPTION The ADN2891 is a 3.2 Gbps limiting amplifier with integrated loss-of-signal (LOS) detection circuitry and a received signal strength indicator (RSSI). This part is optimized for SONET, Gigabit Ethernet (Gb E), and Fibre Channel optoelectronic conversion applications. The ADN2891 has a differential input sensitivity of 4 m V p-p and accepts up to a 2.0 V p-p differential input overload voltage. The ADN2891 supports current mode logic (CML) outputs with controlled rise and fall times. By monitoring the bias current through a photodiode, the onchip RSSI detector measures the average power received with 2% typical linearity over the entire valid input range of the photodiode. The on-chip RSSI detector facilitates SFF-8472pliant optical transceivers by eliminating the need for external RSSI detector circuitry. Additional features include a programmable loss-of-signal (LOS) detector and output squelch. The ADN2891 is available in a 3 mm × 3 mm, 16-lead LFCSP. APPLICATIONS SFP/SFF/GBIC optical transceivers OC-3/OC-12/OC-48, Gb E, Fibre Channel (FC) receivers 10GBASE-LX4 transceivers WDM transponders FUNCTIONAL BLOCK DIAGRAM AVCC AVEE DRVCC DRVCC DRVEE 50Ω 50Ω OUTP OUTN ADN2880 NIN 50Ω 50Ω 3kΩ PD_VCC VREF +V LOS RSSI/LOS DETECTOR 10kΩ RSSI_OUT ADu C7020 PD_CATHODE 05244-001 CAZ1 0.01μF CAZ2 THRADJ SQUELCH Figure 1. Rev. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third...