LMX2320TM National Semiconductor, LMX2320TM Datasheet - Page 19

• Manufacturer Part Number: LMX2320TM
• Description: IC FREQ SYNTH 2.0GHZ 20-TSSOP
• Manufacturer: National Semiconductor
• Series: PLLatinum™r
• Type: PLL Frequency Synthesizerr

Specifications of LMX2320TM

• Pll: Yes
• Input: CMOS, TTL
• Output: CMOS
• Number Of Circuits: 1
• Ratio - Input:output: 1:1
• Differential - Input:output: Yes/No
• Frequency - Max: 2GHz
• Divider/multiplier: Yes/No
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-TSSOP
• Frequency-max: 2.5GHz
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: *LMX2320TM

Application Information
Converting to standard component values gives the follow-
ing filter values, which are shown in Figure 4 .
Note: *See related equation for K in Charge Pump Current Specification
C1 = 560 pF
R2 = 6.8 k
C2 = 2700 pF
R3 = 27 k
C3 = 56 pF
Definitions. For this example V
approximated using the curves in the Typical Performance Character-
istics for Charge Pump Current vs. D
mA. You may also use K = (2.8 mA/2 rad), but in this case you must
convert K
VCO
FIGURE 9. 20 kHz Loop Filter
to (rad/V) multiplying by 2 .
P
= 3.3V. The value for K can then be
o
Voltage. The units for K are in
DS012339-33
(Continued)
19
MEASUREMENT RESULTS (Example # 2)
The reference spurious level is
filter attenuation and the low spurious noise level of the
LMX2320.
FIGURE 10. PLL Reference Spurs
<
−65 dBc, due to the loop
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DS012339-34