Cirrus Logic CS2000-OTP - Manual (Page 22)

CS2000-OTP
22 DS758F2
6. PARAMETER DESCRIPTIONS
As mentioned in Section 5.1 on page 11 , there are two different kinds of parameter configuration sets, Modal and
Global. These configuration sets, shown in Figure 17 , can be programmed in the field using the CDK2000 or pre-
programmed at the factory. Please see “Programming Information” on page 27 for more details.
Figure 17. Parameter Configuration Sets
6.1 Modal Configuration Sets
There are four instances of each of these configuration parameters. Selection between the four stored sets
is made using the M[1:0] pins.
6.1.1 R-Mod Selection (RModSel[1:0])
Selects the R-Mod value, which is used as a factor in determining the PLL’s Fractional N.
Note: This parameter does not take affect unless M2 pin is high and the M2Config[2:0] global param-
eter is set to ‘011’.
RModSel[1:0] R-Mod Selection
00 Right-shift R-value by 1 (÷ 2).
01 Right-shift R-value by 2 (÷ 4).
10 Right-shift R-value by 3 (÷ 8).
11 Right-shift R-value by 4 (÷ 16).
Application: “Ratio Modifier (R-Mod)” on page 15
M[1:0] pins
Modal Configuration Set #0
RModSel[1:0] LockClk[1:0] FracNSrc AuxOutSrc[1:0]
Modal Configuration Set #1
Ratio 1 RModSel[1:0] LockClk[1:0] FracNSrc AuxOutSrc[1:0]
Modal Configuration Set #2
Ratio 2 RModSel[1:0] LockClk[1:0] FracNSrc AuxOutSrc[1:0]
Modal Configuration Set #3
Ratio 3 RModSel[1:0] LockClk[1:0] FracNSrc AuxOutSrc[1:0]
00
01
10
11
Global Configuration Set
RefClkDiv[1:0] ClkOutUnl AuxLockCfg LFRatioCfg M2Config[2:0]
Ratio 0
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ClkIn_BW[2:0]