SKY73121-11 Datasheet, PDF (7/22 Pages) Skyworks Solutions Inc. – 1805 - 1890 MHz High Performance VCO/Synthesizer With Integrated Switch

DATA SHEET • SKY73121-11 VCO/SYNTHESIZER
Table 6. Load Register Word 2 (Programs the Frequency Control 1 Register) (2 of 2)
Parameter
Function
State Description
ndiv
rsvd
mod_reset_f
fract_int_sel
rsvd
me
rsvd
N-divider/prescaler mode for control of M
and A counters [15:6]
Reserved [16]
Modulator reset/fractional mode select [17]
Fractional/integer mode select [18]
Reserved [19]
Modulus extender [23:20]
Reserved [25:24]
Bits [15:6]:
Bits [15:10] Bits [9:6]
M bits [5:0]
M bits [5:0]
A bits [3:0] = use 16/17 prescaler
A bits [2:0] = use 8/9 prescaler
Note: The six MSBs of ndiv denote the M counter value and the four
LSBs denote the A counter value. For the 8/9 prescaler mode, the A
counter value requires only three bits. Therefore, bit [9] of ndiv is a
“don’t care” bit.
Reserved
Bit [17]:
0 = Modulator is reset or disabled
1 = Modulator is in fractional mode
Bit [18]:
0 = Modulator is in integer mode
1 = Modulator is in fractional mode
Reserved. This bit should always remain set (logic high).
These four bits need to be programmed together with bits [12:2] of
Word 3. Bits [23:20] represent the four LSBs ([3:0]) of the 15-bit
modulus extender value (ME [14:0]). Refer to the Synthesizer
Programming section of this Data Sheet for further information.
Reserved
Recommended
Operational Value
(Binary)
Application
dependent
0
1
1
1
Application
dependent
00
Table 7. Load Register Word 3 (Programs the Frequency Control 2 Register)
Parameter
Function
State Description
wd_0, wd_1
me
fn
rsvd
rsvd
Address bits [1:0]. Must be set to 11b (see
Table 3)
Modulus extender [12:2]
Fractional divisor code [20:13]
Reserved [23:21]
Reserved [25:24]
These 11 bits need to be programmed together with bits [23:20] of
Word 2. Bits [12:2] represent the 11 MSBs ([14:4]) of the 15-bit
modulus extender value (ME [14:0]). Refer to the Synthesizer
Programming section of this Data Sheet for further information.
Bits [20:13] represent the 8-bit fractional divisor code (FN [7:0]).
Refer to the Synthesizer Programming section of this Data Sheet for
information.
These three bits should always remain cleared (logic low).
Reserved
Recommended
Operational Value
(Binary)
11
Application
dependent
Application
dependent
0
00
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
200888B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • December 1, 2009
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