Re: AD9959 Evaluation Board X1 Crystal (2400ECSXR)

Hi,

Just to clear things out, X1 crystal is the 24MHz clock used as the reference clock for the CY7C68013A chip.

For AD9959, you have said you were able to work alright with it using external function generator. That is, you set CLK_MODE_SEL = 0 (W11 = REF CLK).

If you will use crystal, then you need to populate X2. This is the reference clock for AD9959.

Also:

• set W11 to XTAL (CLK_MODE_SEL = 1)
• install 0-ohm resistors R52 and R53.
• populate C66 and C67. Values depend on the load capacitance requirement of your crystal
• remove C21 and C22

Best Regards,

Sitti