Hello, I am hoping to use the LTC6953/LTC6952 combination in a ParallelSync operation with the LTC6953 providing the reference distribution in Figure 35 in the LTC6952 datasheet. And the initial configuration of registers are as follows:
LTC6953 - {0x25, 0x08, 0x42, 0xc0, 0xff, 0x03, 0x00, 0x00, 0x00, 0x00, 0x13, 0x00, 0x00, 0x80, 0x00, 0x00, 0x08, 0xc0, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0x00, 0x00, 0x08, 0xc0, 0x01, 0x00, 0x22};
LTC6952#1 - {0x15, 0x2a, 0x00, 0x00, 0x22, 0x22, 0xcc, 0x01, 0x00, 0x14, 0x13, 0x00, 0x98, 0x80, 0x28, 0x00, 0x98, 0x80, 0x28, 0x00, 0x99, 0x80, 0x38, 0x00, 0x99, 0x80, 0x33, 0x00, 0x99, 0x80, 0x29, 0x00, 0x99, 0x80, 0x28, 0x00, 0x9d, 0x80, 0x14, 0x00, 0x9d, 0xf3, 0xd0, 0x00, 0x9d, 0xf3, 0xcb, 0x00, 0x9d, 0xf3, 0xc1, 0x00, 0x9d, 0xf3, 0xc0, 0x00, 0x22};
LTC6952#2 - {0x15, 0x2a, 0x00, 0x02, 0x22, 0x22, 0xcc, 0x01, 0x00, 0x14, 0x13, 0x00, 0x99, 0x80, 0x28, 0x00, 0x99, 0x80, 0x75, 0x00, 0x99, 0x80, 0x6f, 0x00, 0x99, 0x80, 0x61, 0x00, 0x99, 0x80, 0x5e, 0x00, 0x9d, 0xf0, 0x14, 0x00, 0x9d, 0x80, 0x14, 0x00, 0x9d, 0xf4, 0x0d, 0x00, 0x9d, 0xf4, 0x07, 0x00, 0x9d, 0xf3, 0xf9, 0x00, 0x9d, 0xf3, 0xf6, 0x00, 0x22};
Following the example in datasheet, the outputs in LTC6953 which connect to LTC6952 #1,2 EZS-SRQ are set to pass through mode, and the EZS-SRQ in LTC6953 is connected to GND. I am using a 100MHz reference and no dividers in the LTC6953. However, I couldn't catch any pulse in the oscilloscope and those two LTC6952s couldn't be synchronized, that is, the output clocks in LTC6952#1 and LTC6952#2 don't have a fixed phase difference.
Is there anyone able to shed any light as to what I might be doing wrong?
Thanks for any help.
