LMX2531LQ2080E/NOPB National Semiconductor, LMX2531LQ2080E/NOPB Datasheet - Page 23

• Manufacturer Part Number: LMX2531LQ2080E/NOPB
• Description: IC PLL FREQ SYNTH W/VCO 36-LLP
• Manufacturer: National Semiconductor
• Series: PowerWise®r
• Type: Clock/Frequency Synthesizer (RF)r

Specifications of LMX2531LQ2080E/NOPB

• Pll: Yes
• Input: Clock
• Output: CMOS
• Number Of Circuits: 1
• Ratio - Input:output: 2:2
• Differential - Input:output: No/No
• Frequency - Max: 2.274GHz
• Divider/multiplier: Yes/No
• Voltage - Supply: 2.8 V ~ 3.2 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 36-LLP
• Frequency-max: 2.2GHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LMX2531LQ2080ETR

2.2 REGISTER R1
2.2.1 NUM[21:12]
These are the MSB bits in for the fractional numerator that already have been described.
2.2.2 N[10:8] -- 3 MSB Bits for the N Counter
These are the 2 MSB bits for the N counter, which were discussed in the R0 register section.
2.2.3 ICP[3:0] -- Charge Pump Current
This bit programs the charge pump current in from 90 µA to 1440 µA in 90 µA steps. In general, higher charge pump currents yield
better phase noise for the PLL, but also can cause higher spurs.
ICP
10
11
12
13
14
15
0
1
2
3
4
5
6
7
8
9
Charge Pump State
10X
11X
12X
13X
14X
15X
16X
1X
2X
3X
4X
5X
6X
7X
8X
9X
23
Typical Charge Pump Current at 3 Volts
1080
1170
1260
1350
1440
(µA)
180
270
360
450
540
630
720
810
900
990
90
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