LTC6947
Ultralow Noise 0.35GHz to
6GHz Fractional-N Synthesizer
Description Features Low Noise Fractional-N PLL
n No ∆Σ Modulator Spurs
n 18-Bit Fractional Denominator
n 350MHz to 6GHz VCO Input Range
n –226dBc/Hz Normalized In-Band Phase Noise Floor
n –274dBc/Hz Normalized In-Band 1/f Noise
n –157dBc/Hz Wideband Output Phase Noise Floor
n Excellent Integer Boundary Spurious Performance
n Output Divider (1 to 6, 50% Duty Cycle)
n Output Buffer Muting
n Charge Pump Supply from 3.15V to 5.25V
n Charge Pump Current from 1mA to 11.2mA
n Reference Input Frequency Up to 425MHz
n Fast Frequency Switching
n FracNWizardв„ў Software Design Tool Support The LTCВ®6947 is a high performance, low noise, 6GHz
phase-locked loop (PLL), including a reference divider,
phase-frequency detector (PFD), ultralow noise charge
pump, fractional feedback divider, and VCO output divider. n The fractional divider uses an advanced, 4th order Δ∑
modulator which provides exceptionally low spurious
levels. This allows wide loop bandwidths, producing …