SKY73126-31 Datasheet, PDF (3/14 Pages) Skyworks Solutions Inc. – 161.92 MHz High Performance VCO/Synthesizer

DATA SHEET • SKY73126-31 VCO/SYNTHESIZER
The contents of each word in the load register are used to
program the four hold registers described in Tables 4 through 7.
Loading new data into a hold register not associated with the
synthesizer frequency programming does not reset or change the
synthesizer. The synthesizer should not lose lock before, during,
or after a new serial word load that does not change the
programmed frequency.
Vendor ID Read-Back
The SKY73126-31 includes a read-back function that provides the
vendor ID. This information is stored in register word 0 and is
provided by the lock detect output signal (LD, pin 12).
Vendor ID read-back is initiated by setting the MSB of a 32-bit
data word and writing the word to device word address 0 (all
other bits of the data word are “don’t care”). After the LE signal
transitions from low to high, the rising edge of CLK gates the
Word 0 register data (vendor ID) to the lock detect pin, MSB first.
The vendor ID for the SKY73126-31 is 0x100 (equal to
100000000b or 256 decimal).
Figure 5 shows the Serial Peripheral Interface (SPI) timing
diagram for vendor ID read-back. Figure 6 defines the word used
to initiate the vendor ID read-back function.
CLK
DATA
LE
t3 t4
t1 t2
D31
D30
t6
D4
D3
D2
D1
D0
t5
S1192
Figure 3. SKY73126-31 Serial Data Input Timing Diagram (MSB First)
Table 2. CLK, DATA, LE Timing Parameters
Parameter
DATA to CLK setup time (t1)
DATA to CLK hold time (t2)
CLK high duration (t3)
CLK low duration (t4)
CLK to LE hold time (t5)
LE to CLK setup time (t6)
Read-back clock to output time (tdOUT)
>10 ns
>10 ns
>25 ns
>25 ns
>10 ns
>10 ns
<25 ns
Value
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
201112C • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • February 24, 2010
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