LTC6947 Datasheet | Linear Technology

Features n LTC6947 Ultralow Noise 0.35GHz to 6GHz Fractional-N Synthesizer Description The LTC®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. The fractional divider uses an advanced, 4th order Δ∑ 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. The differential, low-noise output buffer has user-programmable output power ranging from - 4.3d Bm to +4.5d Bm, and may be muted through either a digital input pin or software. The ultralow noise charge pump contains selectable high and low voltage clamps useful for VCO monitoring, and also may be set to provide a V+/2 bias. All device settings are controlled through a SPI-patible serial port. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Frac NWizard is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Low Noise Fractional-N PLL n No ∆Σ Modulator Spurs n 18-Bit Fractional Denominator n350MHz to 6GHz VCO Input Range n - 226d Bc/Hz Normalized In-Band Phase Noise Floor n - 274d Bc/Hz Normalized In-Band 1/f Noise n - 157d Bc/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 1m A to 11.2m A n Reference Input Frequency Up to 425MHz n Fast Frequency Switching n Frac NWizard™ Software Design Tool Support Applications n n n n n Wireless Basestations (LTE, Wi MAX, W-CDMA, PCS) Broadband Wireless Access Microwave Data Links Military and Secure Radio Test and Measurement Typical Application 11GH...