Kaiam selects Ensphere’s 10G shunt laser driver for 40G quad transmit sub-assembly

SANTA CLARA, USA: Ensphere Solutions, an emerging leader in advanced communications semiconductor ICs, announced the adoption of Ensphere Solutions’ ESI-1010 10G shunt laser driver by Kaiam Corporation. This driver will be used in Kaiam’s new 40G compact QSFP+ Transmit Optical Subassembly (TOSA).

Kaiam, an emerging company with a breakthrough hybrid optical integration technology, successfully demonstrated a new QSFP+ transmitter and receiver optical subassemblies (ROSA) for 40GBASE-LR4 applications at OFC/NFOEC 2011 in Los Angeles. The 4 channel by 10Gb/s TOSA and ROSA transmit and receive, respectively, a cumulative 40Gb/s in a single mode fiber with a 10km reach. The technology is able to achieve the very high densities needed for such compact transceivers.

Kaiam’s new TOSA and ROSA have raised the bar for the power dissipation, density, and manufacturing cost of 40G optical modules. This has been accomplished by using proprietary micromechanics to solve the alignment issues and build hybrid photonic integrated circuits (PICs).

“The next generation 40Gb/s pluggable modules (QSFP+) for single mode fiber require more than an order of magnitude reduction in area. ESI-1010 has been a key element, allowing us to increase the density while simultaneously reducing power dissipation and improving signal integrity,” said Dr. Thomas Schrans, Kaiam’s VP of Engineering and Product Development.

“We are extremely pleased for having the opportunity to work with Kaiam. Their extensive background in optics and deep appreciation of system-level issues has enabled us to optimize the performance of ESI-1010,” said Hessam Mohajeri, Ensphere’s Chief Executive Officer.

ESI-1010 is a single channel 10G laser diode driver (LDD) able to support a wide variety of laser RC time constants. It is capable of supplying up to 100 mA of bias and 50 mA of modulation currents. In a shunt configuration, ESI-1010 assumes the heavy burden of driving a low impedance laser diode while presenting a 50Ω load to the preceding driver, which is far easier to drive.