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ADF5904 register 1 reserved field is changing

Category: Datasheet/Specs
Product Number: ADF5904

Hello Dear, 

I am writing driver for  ADF5904 and I noticed that there is something strange in the initialization sequence given in the datasheet.

There is a reserved field in R1 and it is changing in step 7. Is it something wrong or is there any explanation for this?

Best regards,

Parents
  • Hi the init sequence shown in table 6 is correct. Those reserved bits in register 1 contain various settings which are used to tune the bias of the LNA, mixer and LO input blocks which in turn affects the performance (gain, noise figure and P1dB mainly). During characterization we found what the optimum values were and so set those registers as reserved in the documentation. I agree the datasheet register map section and figure 20 is somewhat confusing since those bits will not always be set as per figure 20. But the init sequence does have the correct procedure so please go by that

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  • Hi the init sequence shown in table 6 is correct. Those reserved bits in register 1 contain various settings which are used to tune the bias of the LNA, mixer and LO input blocks which in turn affects the performance (gain, noise figure and P1dB mainly). During characterization we found what the optimum values were and so set those registers as reserved in the documentation. I agree the datasheet register map section and figure 20 is somewhat confusing since those bits will not always be set as per figure 20. But the init sequence does have the correct procedure so please go by that

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