Frequency (MHz)
RE
F Spu
r (d
B
c)
0
500
1000 1500 2000 2500 3000 3500 4000 4500
-150
-145
-140
-135
-130
-125
-120
-115
-110
-105
-100
-95
-90
-85
-80
-75
-70
D213
T
A
= -40
q
C
T
A
= 25
q
C
T
A
= 85
q
C
Frequency (MHz)
RE
F Spu
r (d
B
c)
0
500
1000 1500 2000 2500 3000 3500 4000 4500
-150
-145
-140
-135
-130
-125
-120
-115
-110
-105
-100
-95
-90
-85
-80
-75
-70
D214
V
CC
= 3.15,4.75
V
CC
= 3.30,5.00
V
CC
= 3.45,5.25
Frequency (MHz)
P
F
D
Spu
r (d
B
c)
0
500
1000 1500 2000 2500 3000 3500 4000 4500
-150
-145
-140
-135
-130
-125
-120
-115
-110
-105
-100
-95
-90
-85
-80
-75
-70
D108
1 x PFD
2 x PFD
3 x PFD
Frequency (MHz)
P
F
D
Spu
r (d
B
c)
0
500
1000 1500 2000 2500 3000 3500 4000 4500
-150
-145
-140
-135
-130
-125
-120
-115
-110
-105
-100
-95
-90
-85
-80
-75
-70
D227
PFD = 0.68MHz
PFD = 1.28MHz
PFD = 2.56MHz
Frequency (MHz)
P
F
D
Spu
r (d
B
c)
0
500
1000 1500 2000 2500 3000 3500 4000 4500
-150
-145
-140
-135
-130
-125
-120
-115
-110
-105
-100
-95
-90
-85
-80
-75
-70
D106
T
A
= -40
q
C
T
A
= 25
q
C
T
A
= 85
q
C
Frequency (MHz)
P
F
D
Spu
r (d
B
c)
0
500
1000 1500 2000 2500 3000 3500 4000 4500
-150
-145
-140
-135
-130
-125
-120
-115
-110
-105
-100
-95
-90
-85
-80
-75
-70
D107
V
CC
= 3.15,4.75
V
CC
= 3.30,5.00
V
CC
= 3.45,5.25
26
SLWS245B – MAY 2014 – REVISED FEBRUARY 2017
Product Folder Links:
Copyright © 2014–2017, Texas Instruments Incorporated
Typical Characteristics - PLL/VCO (continued)
Unless specified all plots were created using TRF3722EVM, VCC = 3.3 V, VCC_TK = 5 V, and T
A
= 25°C. Measured at
LO_OUTP with 50
Ω
bias resistor and 47 pF series capacitor. Modulator section powered down. Reference frequency is set
to 61.44 MHz. Optimized bias settings as per
.
Figure 94. PFD Spur vs Temperature
Figure 95. PFD Spur vs Supply
Figure 96. PFD Spur vs PFD Multiples
Figure 97. PFD Spur vs Frequency
Figure 98. 1 x Reference Spur vs Temperature
Figure 99. Reference Spur vs Supply