TIA technology enhances optical receiver performance

Westlake Village, Calif. — Inphi Corp. claims these integrated linear transimpedance amplifiers (TIAs) can operate at data rates up to 11.3 Gbits/s, and amplify input currents over the entire dynamic range required by the upcoming IEEE 10GBASE-LRM standard — with less than 5 percent total harmonic distortion (THD).

Low THD preserves the input data characteristics and allows an electronic dispersion compensation (EDC) circuit in the receiver to easily recover data from a distorted signal, said Kevin Nary, Inphi's vice president of engineering.

The 1348TA and 1349TA TIAs, with automatic gain control, are essential for optical receivers used in 1310-nm multimode fiber links employing EDC engines that recover signals distorted by multi-path propagation. The primary application is for 10 Gbits/s Ethernet as defined by the 10GBASE-LRM (long reach over multimode fiber) specification. The 1348TA is intended for TO-can receivers, while the 1349TA targets butterfly receivers.

The 1348TA and 1349TA are the only linear TIAs available that leverage through-wafer via (TWV) technology, according to Inphi. This feature simplifies the internal package assembly by eliminating ground bond wires and reducing the number of bypass caps. More importantly, TWVs enhance optical receiver
performance by maintaining a flat gain versus frequency profile, increasing the output return loss and decreasing cross talk and jitter, Nary said.

The 1348TA/1349TA have a small-signal bandwidth greater than 8 GHz as well as an output return loss of greater than 8 dB, up to 12 GHz. The TIA/AGC operates from a single 3.3-volt power supply with power consumption of 200 milliwatts.

Click here for a photo of Inphi's 1348TA assembled in a TO-46 header for a 10-Gbit Ethernet Application

Samples are available now with volume production planned for Q2 2006. Both TIAs are available in die form. The parts are expected to cost $19.00 per unit in small quantity. Click here to request the 1348TA/1349TA data sheets.

Inphi Corp. , 1-805-446-5100,

0 comments on “TIA technology enhances optical receiver performance

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.