3.2 Gbps 3.3V Low Noise TIA for Small Form Factors

The ADN2880 is a 3.3 V, high gain SiGe transimpedance amplifier (TIA). The TIA converts the small signal current of a photo detector into differential voltage output. The ADN2880 features a 315 nA typical input-referred noise, enabling an optical sensitivity of −24.2 dBm (0.85 A/W PIN). With a bandwidth of 2.5 GHz, the ADN2880 allows a data rate operation up to 3.2 Gbps. Typical power dissipation is approximately 70 mW.

To facilitate the assembly in small form factor packages, such as TO-46 headers, the ADN2880 provides an on-chip RC filter (200 Ω, 20 pF) and features a 20 kHz low frequency cutoff without using an external capacitor. An on-chip RSSI circuit, which generates a voltage proportional to the average photo-diode current, is also available for power monitoring and assembly alignment.

The ADN2880 is available in die form. With a chip area of 1.2 mm × 0.7 mm, the TIA layout is specifically optimized for TO-Can-based packages.

Applications

* 3.2 Gbps or below optical receivers

* SONET/GbE/FC optical receivers

* SFF-8472-compliant receivers

* PIN/APD-TIA receive optical subassemblies (ROSA)

* Bandwidth: 2.5 GHz

* Optical sensitivity: −24.2 dBm

* Differential transimpedance: 4400 V/A

* Power dissipation: 70 mW

* Differential output swing: 260 mV p-p

* Input overload current: 4.3 mA p-p

* On-chip RSSI function

* Low frequency cutoff: 20 kHz

* On-chip PD filter: RF = 200 Ω, CF= 20 pF

* Die size: 0.7 mm x 1.2 mm