LMX2572: Sequence for Changing Frequencies

Masakazu Adachi

Part Number: LMX2572

Hello team,

Please advise on the recommended sequence for changing frequencies.

When changing from f0 to f1, only the register with the change is rewritten to save time, and R0 with FCAL_EN = 1 is written.

However, after the write, it enters the unlocked state.

When changing from f0 to f1, if all registers are set, it locks normally.

Let me know what you think.

Regards,

Adachi

+1 Noel Fung over 4 years ago

Hi Adachi-san,

After f0 is locked, and then you want to switch the frequency to f1, only those related registers (e.g. PLL_N, PLL_NUM) and R0 are needed to program.

Could you share your register configuration and the exact sequence when you switch it to a new frequency?

0 Masakazu Adachi over 4 years ago in reply to Noel Fung

Hi Noel-san,

Thank to the support.

The customer had set R0 b1 to Resets all registers.

They were able to confirm that it works by removing this setting.

Regards,

Adachi

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