Overview
CS6718 integrated two main functions in a single chip
providing optimal solutions for various fiber module
applications. The functional blocks include a 1.25G post-
amplifier, a continuous mode LD driver.
The post-amplifier receives AC coupled differential
signal from pre-amplifier and performs the quantization
amplifications. There are total four amplification stages
excluding the output stage. The offset cancellation is
built-in on chip. The output of the post-amplifier is
configured as PECL. The LOS power threshold level is
configurable by SD_SET voltage.
The LD driver performs the transmit function that
receives the PECL differential signal TXINP/TXINN and
convert to drive LD output driver. The LD driver is also
controlled by TX_DIS signal. The laser driver includes
differential modulation outputs and DC bias control
output. The setting of output power level is controlled
through automatic power control loop and is configurable
by RMPD. The setting of output power modulation level is
configurable by MOD_SET voltage. The output can be
connected to Laser diode either by AC or DC coupled.
CS6718 integrates essential building blocks for Fiber
module design. Using CS6718, the module can achieve
low cost and high performance fiber module and can be
applied in FTTH, BPON, and GEPON.
APPLICATIONS
SONET/SDH, FTTH, GEPON.