Low-Jitter 155MHz/622MHz Clock Generator
AC ELECTRICAL CHARACTERISTICS (continued)
(VCC = +3.3V ±10% or VCC = +5.0V ±10%, TA = -40°C to +85°C. Typical values are at VCC = +3.3V and TA = +25°C, unless other-
wise noted.) (Note 5)
PARAMETER
PLL SPECIFICATIONS
PLL Jitter Transfer Bandwidth
Jitter Transfer Peaking
OPAMP SPECIFICATION
Unity-Gain Bandwidth
VCO INPUT SPECIFICATIONS
VCO Input Frequency
VCO Input Slew Rate
SYMBOL
CONDITIONS
BW
(Note 10)
FJITTER ≤ BW (Note 11)
fVCO
MIN TYP MAX UNITS
30
10,000 Hz
0.1
dB
7
MHz
622/155 700
0.5
MHz
V/ns
Note 1: Specifications at -40°C are guaranteed by design and characterization.
Note 2: Measured with PECL outputs unterminated.
Note 3: OPAMP specifications met with 10kΩ load to ground or 5kΩ load to VCC (POLAR = 0 and POLAR = VCC).
Note 4: PFD/CP currents are measured from pins OPAMP+ to OPAMP-. See Table 4 for gain settings.
Note 5: AC characteristics are guaranteed by design and characterization.
Note 6: Measured with 50% VCO input duty cycle.
Note 7: Random noise voltage at op amp output with 800kΩ resistor connected between VC and OPAMP-, PFD/CP gain (KPD) =
5µA/UI, and POLAR = 0. Measured with the PLL open loop and no REFCLK or VCO input.
Note 8: Spurious noise voltage due to PFD/CP output pulses measured at op amp output with R1 = 800kΩ, KPD = 5µA/UI, and com-
pare frequency 400 times greater than the higher-order pole frequency (see the Design Procedure section).
Note 9: PSR measured with a 100mVP-P sine wave on VCC in a frequency range from 100Hz to 2MHz. External resistors R1 matched
to within 1%, external capacitors C1 matched to within 10%. Measured closed loop with PLL bandwidth set to 200Hz.
Note 10: The PLL 3dB bandwidth is adjusted from 30Hz to 10kHz by changing external components R1 and C1, by selecting the
internal programmable divider ratio and phase-detector gain. Measured with VCO gain of 150ppm/V and C1 limited to 2.2µF.
Note 11: When input jitter frequency is above PLL transfer bandwidth (BW), the jitter transfer function rolls off at -20dB/decade.
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