ADF4252BCPZ-R7

锁相环 - PLL 1000-2500MHz Frac-N PLL

Product Details

The ADF4252 is a dual fractional-N/integer-N frequency synthesizer that can be used to implement local oscillators LO in the upconversion and downconversion sections of wireless receivers and transmitters. Both the RF and IF synthesizers consist of a low noise digital phase frequency detector PFD, a precision charge pump, and a programmable reference divider. The RF synthesizer has a Σ-Δ-based fractional interpolator that allows programmable fractional-N division. The IF synthesizer has programmable integer-N counters. A complete phase-locked loop PLL can be implemented if the synthesizer is used with an external loop filter and voltage controlled oscillator VCO.

Control of all the on-chip registers is via a simple 3-wire interface. The device operates with a power supply ranging from 2.7 V to 3.3 V and can be powered down when not in use.

Applications

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Base stations for mobile radio GSM, PCS, DCS, CDMA, WCDMA

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Wireless handsets GSM, PCS, DCS, CDMA, WCDMA

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Wireless LANs

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Communications test equipment

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CATV equipment

### Features and Benefits

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3.0 GHz fractional-N/1.2 GHz integer-N

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2.7 V to 3.3 V power supply

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Separate VP allows extended tuning voltage to 5 V

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Programmable dual modulus prescaler

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RF: 4/5, 8/9

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* IF: 8/9, 16/17, 32/33, 64/65

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Programmable charge pump currents

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3-wire serial interface

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Digital lock detect

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Power-down mode

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Programmable modulus on fractional-N synthesizer

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Trade off noise vs. spurious performance