Hi Chandu,
When powering on properly, the DOTP1 LED should be on. Before powering up, do you have the jumper J_SUB connect properly? If you are using 2 power supplies for VSUB & VNN, then you need to connect pin 2 & 3 of J_SUB together. You can try to replace just the LM96551. But I am afraid, the LM96530 is damages too. Notice that TX_SDK_V1 eval board is for LM96551 pulser. If you are looking for the LM96550, you need the TX_SDK_V2 eval board.
Regards,
Charles