Rev E 11/12/14 4 FEMTOCLOCK®, CRYSTAL-TO-LVCMOS/LVTTL FREQUENCY
SYNTHESIZER
840002-01 DATA SHEET
Table 4. Crystal Characteristics
NOTE: Characterized using an 18pF parallel resonant crystal.
AC Electrical Characteristics
Table 5A. AC Characteristics, V
DD
= V
DDA
= V
DDO
= 3.3V±5%, T
A
= -30°C to 85°C
NOTE: Electrical parameters are guaranteed over the specified ambient operating temperature range, which is established when the device is
mounted in a test socket with maintained transverse airflow greater than 500 lfpm. The device will meet specifications after thermal equilibrium
has been reached under these conditions.
NOTE 1: Defined as skew between outputs at the same supply voltage and with equal load conditions. Measured at V
DDO
/2.
NOTE 2: This parameter is defined in accordance with JEDEC Standard 65.
NOTE 3: Refer to Phase Noise Plot.
Table 5B. AC Characteristics, V
DD
= V
DDA
= 3.3V±5%, V
DDO
= 2.5V±5%, T
A
= -30°C to 85°C
For NOTES, see Table 5A above.
Parameter Test Conditions Minimum Typical Maximum Units
Mode of Oscillation Fundamental
Frequency 25 MHz
Equivalent Series Resistance (ESR) 50
Shunt Capacitance (C
O
) 7pF
Drive Level 1mW
Symbol Parameter Test Conditions Minimum Typical Maximum Units
f
OUT
Output Frequency
F_SEL[1:0] = 00 140 175 MHz
F_SEL[1:0] = 01 or 11 112 140 MHz
F_SEL[1:0] = 10 56 70 MHz
tsk(o) Output Skew; NOTE 1, 2 12 ps
tjit(Ø)
RMS Phase Jitter, Random;
NOTE 3
156.25MHz, (1.875MHz - 20MHz) 0.47 ps
125MHz, (1.875MHz - 20MHz) 0.57 ps
62.5MHz, (1.875MHz - 20MHz) 0.51 ps
t
R
/ t
F
Output Rise/Fall Time 20% to 80% 200 700 ps
odc Output Duty Cycle 46 54 %
Symbol Parameter Test Conditions Minimum Typical Maximum Units
f
OUT
Output Frequency
F_SEL[1:0] = 00 140 175 MHz
F_SEL[1:0] = 01 or 11 112 140 MHz
F_SEL[1:0] = 10 56 70 MHz
tsk(o) Output Skew; NOTE 1, 2 12 ps
tjit(Ø)
RMS Phase Jitter, Random;
NOTE 3
156.25MHz, (1.875MHz - 20MHz) 0.47 ps
125MHz, (1.875MHz - 20MHz) 0.55 ps
62.5MHz, (1.875MHz - 20MHz) 0.49 ps
t
R
/ t
F
Output Rise/Fall Time 20% to 80% 200 700 ps
odc Output Duty Cycle
46 54 %
f
OUT
= 125MHz 47 53 %
