LMX2531LQ1500E_08 Datasheet, PDF (20/24 Pages) National Semiconductor (TI) – High Performance Frequency Synthesizer System with Integrated VCO

2.7 REGISTER R6
2.7.1 C3_C4_ADJ[2:0] -- VALUE FOR C3 AND C4 IN THE INTERNAL LOOP FILTER
C3_C4_ADJ
0
1
2
3
4
5
6
7
C3 (pF)
50
50
50
100
150
100
50
50
C4 (pF)
50
100
150
50
50
100
150
150
2.7.2 R3_ADJ_FL[1:0] -- Value for Internal Loop Filter Resistor R3 During Fastlock
R3_ADJ_FL Value
0
1
2
3
R3 Resistor During Fastlock (kΩ)
10
20
30
40
2.7.3 R3_ADJ[1:0] -- Value for Internal Loop Filter Resistor R3
R3_ADJ
0
1
2
3
R3 Value (kΩ)
10
20
30
40
2.7.4 R4_ADJ_FL[1:0] -- Value for Internal Loop Filter Resistor R4 During Fastlock
R4_ADJ_FL
0
1
2
3
R4 Value during Fast Lock (kΩ)
10
20
30
40
2.7.5 R4_ADJ[1:0] -- Value for Internal Loop Filter Resistor R4
R4_ADJ
0
1
2
3
R4 Value (kΩ)
10
20
30
40
2.7.6 EN_LPFLTR-- Enable for Partially Integrated Internal Loop Filter
The Enable Loop Filter bit is used to enable/disable the 3rd and 4th pole on-chip loop filters.
EN_LPFLTR
0
1
3rd and 4th Poles of Loop Filter
disabled
(R3 = R4 = 0 ohms and C3 + C4 = 200pF)
enabled
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