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about HMC834 SPI write and eval-board clk

Question asked by jay1 on Jan 26, 2016
Latest reply on Feb 10, 2016 by dyoung1

hi

I'm recently working with the Hittite HMC834(PLL with integrated VCO).

i'm a new starter about this field, and i have some questions about SPI writing 


1.i found out that the length of the register(to write) is not a multiple of the 8. thus i made some signal with the GPIO pins. this is available?(about 100 KHz clk)

 

2.when i check the evaluation software, and i've found that the eval-software offers the register value as below

 

------------------------

REVISION 3.2.4.0

REG 0 A7975

REG 1 2

REG 2 1

REG 3 50

REG 5 6090

REG 6 2003CA

REG 7 14D

REG 8 C1BEFF

REG 9 147FFF

REG A 2046

REG B 7C061

REG C 0

REG D 0

REG E 0

REG F 1

REG 10 39

REG 11 80013

REG 12 3

REG 13 1259

REG 14 0

REG 15 0

REG 16 0

REG 17 0

REG 18 0

REG 19 0

REG 1A 0

REG 1B 0

REG 1C 0

REG 1D 0

REG 1E 0

REG 1F 0

REG 4 0

XTAL 50

DIVIDER_MANUAL_MODE 0

VCO_TO_SYNTH_DIV 1

VCO_TO_OUT_DIV 1

--------------------------------------

upper one is just example,

if i send the register values, from reg00 to reg 1F, it will properly work?

 

3. when i check the Datasheet of the HMC834, registers do not have the address about the each register(only values).

for example, i found out that reg00 and reg04 is 24bit, if i send the 24 bit data, i cannot sure that which register will recieve the 24bit data.

is there any sequence to write?

 

4. it has the 50MHz clk on the eval board. when i put the 10MHz reference clk on the ref port(SMA), the PLL is working with the 50MHz?

the clk applied to the HMC834 IC is only controllable with the SW1 switch with the eval board?

 

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