HMC783(764,765,807) userguide error?

Question

I'm using HMC783 in my design recently, but I find the user guide of hmc783 is incompatible with it, while it is similar to hmc700 about register discription on Reg 0Dh GPO_SPI_RDIV Register (page A-21). The user guide mentions D1 & D0 pins, but HMC783 does not have these pins. I'd like to watch the REFDIV output signal on LD_SDO pin to check whether the chip is working or not. So can anyone give some advice about HMC783 ? Thank you very much ! 
 My email is nuaa0409@163.com .

MRichardson · Accepted Answer

Hi there, 
 You are correct in that these pins which appear on the HMC700 stand alone PLL are not available on the HMC783LP6CE Integrated VCO/PLL synthesizer. The user guide is wrong. Since it sounds like you're not using the evaluation board, I recommend reading back REG 0Fh, should be '1' if locked. Can also view output on spectrum analyzer by probing RFout (and / or REF input) with 50Ω 'sniffer' made from an SMA with a short piece of coax with exposed center conductor. You can use the attached 12GHz, 50MHz REF / PFD Integer mode register file as a starting point, simply adjust the settings based on your reference & PFD frequency. 
 Best Regards, 
 Marty

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HMC783(764,765,807) userguide error?