SI5345 Datasheet, PDF (9/62 Pages) Silicon Laboratories – 10-CHANNEL, ANY-FREQUENCY, ANY-OUTPUT JITTER ATTENUATOR/CLOCK MULTIPLIER

Si5345/44/42
Table 5. Differential Clock Output Specifications
(V_DD = 1.8 V ±5%, V_DDA = 3.3V ±5%, V_DDO = 1.8 V ±5%, 2.5 V ±5%, or 3.3 V ±5%, T_A = –40 to 85 °C)
Parameter
Symbol
Test Condition
Min Typ Max Unit
Output Frequency
Duty Cycle
Output-Output Skew
f_OUT
DC
T_SK
f_OUT < 400 MHz
400 MHz < f_OUT < 712.5 MHz
Outputs on same Multisynth
(Normal Mode)
0.0001 —
48
—
45
—
—
20
712.5
52
55
50
MHz
%
%
ps
Outputs on same Multisynth
(Low-Power Mode)
—
20 100
ps
OUT-OUT Skew
T_{SK_OUT} Measured from the positive to negative —
0
100
ps
output pins
Output Voltage Swing¹ Normal Mode
V_OUT
V_DDO = 3.3 V or
2.5 V or 1.8 V
V_DDO = 3.3 V or 2.5 V
LVDS
LVPECL
350 470 550 mVpp_se
660 810 1000 mVpp_se
Low-Power Mode
V_OUT
V_DDO = 3.3 V or
2.5 V or 1.8 V
LVDS
300 420 530 mVpp_se
V_DDO = 3.3 V or 2.5 V
LVPECL
620 820 1060 mVpp_se
Note:
1. For normal and low-power modes, the amplitude and common-mode settings are programmable through register
settings and can be stored in NVM. Each output driver can be programmed independently. The typical normal mode (or
low-power mode) LVDS maximum is 100 mV (or 80 mV) higher than the TIA/EIA-644 maximum. Also note that the
output voltage swing specifications are given in peak-to-peak single-ended swing.
2. Not all combinations of voltage swing and common mode voltages settings are possible. See the Si5345/44/42 Family
Reference Manual for details.
3. Driver output impedance depends on selected output mode (Normal, Low-Power).
4. Measured for 156.25 MHz carrier frequency. Sinewave noise added to VDDO
(1.8 V = 50 mVpp, 2.5 V/3.3 V = 100 mVpp) and noise spur amplitude measured.
5. Measured across two adjacent outputs, both in LVDS mode, with the victim running at 155.52 MHz and the aggressor
at 156.25 MHz. Refer to “AN862: Optimizing Si534x Jitter Performance in Next Generation Internet Infrastructure
Systems” for guidance on crosstalk optimization. Note that all active outputs must be terminated when measuring
crosstalk.
Rev. 1.0
9