I'm working with the PLL VCO HMC830.
I want to use a look-up table (LUT) for manual calibration, as decribe in "Frequency Hopping with Hittite PLLVCOs Application Note" (attached) (https : // www . hittite.com/content/documents/application_notes/Fast_Frequency_Hopping_Application_Note.pdf).
It should have equivalence between the desired frequency and capacitors switches configuration (Reg 10h Register Tune VCO).
I wonder if somebody already have those data and could provide it.
Thank you very much in advance.
We have another question: Which sequence needs to be sent in manual mode? We configure the PLL registers in the following order in manual mode:
1 Reg 0A (bit 11 = 1 , Bypass VCO Tuning)
2 VCO_Reg 02h K (K>1 or K=1, depending on the frequency required)
3 Reg 05h 00 (Recommended in Datasheet)
4 Reg 03h Integer Part
5 Reg 04h Fractional Part
6 VCO_Reg 00h Tuning (LUT Table data)
Each time a frequency is set we need to program Reg 0A to remain in Manual mode.
If we program Reg 03 (Nint) and Reg 04 (Nfrac) before VCO_Reg 02h, then the sequence does not work.
Please, could you help us?, thank you very much.
Once autocal is turned off (Reg 0x0A=1) it should stay off unless you perform a soft reset ( Reg 0x00=1). Can you read Reg 0x0A during the manual tuning procedure to see if it has changed from "1" to "0"?
Manual tuning should work when Nint and Nfrac are set before the output divider (VCO_Reg 02h). You do not need step #3 (Reg 05h 00) since autocal is off.