Addendum to “DELIC Clock System Synchronization”

The DELIC Clock System Synchronization is described in the DELIC-LC PEB 20570/DELIC-PB PEB 20571 Data Sheet, independent of the version (2.1 .. 3.1).
As an addendum to chapter “DELIC Clock System Synchronization” of the DELICLC/DELIC-PB Data Sheet the following describes the system behaviour when using the VIP PEB 20590 or PEB 20591 in LT-T mode, for example when synchronizing to the Central Office.

When the Central Office is activated, its clock signal is retrieved by the RxPLL of the VIP and a 1.536 MHz reference signal is generated and used as input signal for the DELIC DCXO (pin XCLK). This signal is divided down to 8 kHz and used as input for the DCXO phase detector (PD). The second input to PD is another 8 kHz signal which originates from the 16.384 MHz output of the DCXO.

The DELIC PLL multiplies the 16.384 MHz DCXO signal up to 61.44 MHz. A divider generates the 15.36 MHz layer 1 clock which is used to clock the VIP.