Features
- Low Noise Fractional-N PLL with Integrated VCO
- No Δ-Σ Modulator Spurs
- 18-Bit Fractional Denominator
- –226 dBc/Hz Normalized In-Band Phase Noise Floor
- –274 dBc/Hz Normalized In-Band 1/f Noise
- –157 dBc/Hz Wideband Output Phase Noise Floor
- Excellent Integer Boundary Spurious Performance
- Output Divider (1 to 6, 50% Duty Cycle)
- Output Buffer Muting
- Reference Input Frequency Up to 425MHz
- Fast Frequency Switching
- FracNWizard™ Software Design Tool Support
Typical Application
Description
The LTC®6948 is a high performance, low noise, 6.39GHz phase-locked loop (PLL) with a fully integrated VCO, including a reference divider, phase-frequency detector (PFD), ultralow noise charge pump, fractional feedback divider, and VCO output divider.
The fractional divider uses an advanced, 4th order ΔΣ modulator which provides exceptionally low spurious levels. This allows wide loop bandwidths, producing extremely low integrated phase noise values.
The programmable VCO output divider, with a range of 1 through 6, extends the output frequency range.
For more detail: LTC6948 – Ultralow Noise 0.37GHz to 6.39GHz Fractional-N Synthesizer with Integrated VCO
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