Datasheet

LMX2541SQ2060E, LMX2541SQ2380E
LMX2541SQ2690E, LMX2541SQ3030E
LMX2541SQ3320E, LMX2541SQ3740E
www.ti.com SNOSB31I –JULY 2009–REVISED FEBRUARY 2013
C3_LF C3 (pF)
14 35
15 36
C4_LF[3:0] -- Value for C4 in the Internal Loop Filter
This word controls the state of the internal loop filter resistor C4_LF when the device is Full Chip Mode.
C4_LF C4 (pF)
0 0
1 5
2 20
3 25
4 40
5 45
6 60
7 65
8 100
9 105
10 120
11 125
12 140
13 145
14 160
15 165
Register R3
This register controls miscellaneous features of the device.
MODE[1:0] -- Operational Mode
The LMX2541 can be run in several operational modes as listed in the table below:
MODE Name Divider PLL VCO
0 Full Enabled Enabled Enabled
1 External VCO Enabled Enabled Disabled
2 Divider Only Enabled Disabled Disabled
3 Test (Reserved) Enabled Enabled Enabled
Powerdown -- Powerdown Bit
Enabling this bit powers down the entire device, although register and VCO calibration information is retained.
XO - Crystal Oscillator Mode Select
When this bit is enabled, a crystal with appropriate load capacitors can be attached between the OSCin and
OSCin* pins in order to form a crystal oscillator.
CPG[4:0] -- Charge Pump Current
This word programs the charge pump current gain. The current is programmable between 100 uA and 3.2 mA in
100 uA steps.
CPG Charge Pump State Typical Charge Pump Current (µA)
0 1X 100
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Product Folder Links: LMX2541SQ2060E LMX2541SQ2380E LMX2541SQ2690E LMX2541SQ3030E
LMX2541SQ3320E LMX2541SQ3740E