
Programming Description (Continued)
R2 REGISTER
The R2 Register address bits (R2 [1:0]) are “10”.
The IF_CUR [1:0] bits program the IF charge pump current. Considering the external IF VCO and loop filter, the user can select
the amount of IF charge pump current to be 100A, 200A, 300A or 800A.
R2 REGISTER
Register
MSB
SHIFT REGISTER BIT LOCATION
LSB
23
22
21
20
19
18
17
16
15
14
13
12
11
10
987654321
0
Data Field
Address
Field
R2
(Default)
IF_
CUR[1:0]
00100111011
01
0
1
00010
10
Name
Functions
IF_CUR [1:0]
IF Charge Pump Current
00 = 100 A
01 = 200 A
10 = 300 A
11 = 800 A
LMX2522/LMX2532
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