ZHCSME1C August 2018 – June 2021 DS250DF230
PRODUCTION DATA
The CTLE in the DS250DF230 is a fully-adaptive equalizer. The CTLE adapts according to a Figure of Merit (FOM) calculation during the lock acquisition process. The FOM calculation is based upon the horizontal eye opening (HEO) and vertical eye opening (VEO). Once the CDR locks and the CTLE adapts, the CTLE boost level is frozen until a manual re-adapt command is issued or until the CDR re-enters the lock acquisition state. The CTLE can be re-adapted by resetting the CDR.
The CTLE consists of 4 stages, with each stage having 2-bit boost control. This allows for many boost combinations, including bypassing the first three stages EQs. The CTLE adaption algorithm allows the CTLE to adapt through 20 of these boost combinations. These 20 boost combinations comprise the EQ Table in the channel registers. See channel registers 0x40 through 0x53.
The boost levels can be set between approximately 0 dB and 25 dB (at 12.89 GHz.)