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Products => Computers => Programming => Topic started by: Scratch.HTF on September 30, 2021, 08:23:53 am

Title: Pointers for writing a PLL/VCO library
Post by: Scratch.HTF on September 30, 2021, 08:23:53 am

When I was writing four PLL/VCO libraries (ADF4351/ADF4355/HMC830/MAX2870), these pointers came to mind which I had to adjust accordingly:

• Bits which must be set as appropriate corresponding to an Integer (all Fraction values = 0) or Fractional (any Fraction value not 0) mode
• Charge Pump and Bleed settings which may be dependent on VCO frequency or integer (N) value
• Double buffering enable for certain bits in registers (including RF dividers) which will be latched on writing a certain register
• VCO feedback (divided/fundamental) source
• Prescaler based on VCO frequency
• Lock Detect cycle count and timeout settings
• ADC clock divider
• MUX OUT pin logic level

There may be more which need to be checked, but this was enough to get my libraries working.