LMX2522 Datasheet | National Semiconductor

Description LMX2522 and LMX2532 are highly integrated, high performance, low power frequency synthesizer systems optimized for Korean PCS (K-PCS) with GPS and Korean Cellular (K-Cellular) with GPS, CDMA (1x RTT, IS-95) mobile handsets. Using a proprietary digital phase locked loop technique, LMX2522 and LMX2532 generate very stable, low noise local oscillator signals for up and down conversion in wireless munications devices. LMX2522 and LMX2532 include a RF voltage controlled oscillator (VCO), a GPS VCO, a loop filter, and a fractional-N RF PLL based on a delta sigma modulator. In concert these blocks form a closed loop RF and GPS synthesizer system. LMX2522 supports the Korean PCS band with GPS and LMX2532 supports the Korean Cellular band with GPS. LMX2522 and LMX2532 include an Integer-N IF PLL also. For more flexible loop filter designs, the IF PLL includes a 4-level programmable charge pump. Together with an external VCO and loop filter, LMX2522 and LMX2532 make a plete closed loop IF synthesizer system. Serial data is transferred to the device via a three-wire MICROWIRE interface (DATA, LE, CLK). Operating supply voltage ranges from 2.7 V to 3.3 V. LMX2502 and LMX2512 feature low current consumption: 17 m A at 2.8 V. LMX2522 and LMX2532 are available in a 28-pin leadless leadframe package (LLP). Features n Small Size Small 5.0 mm x 5.0 mm x 0.75 mm 28-Pin LLP Package n RF/GPS Synthesizer System Integrated RF VCO Integrated GPS VCO Integrated Loop Filter Low Spurious, Low Phase Noise Fractional-N RF PLL Based on 11-bit Delta Sigma Modulator 10 k Hz Frequency Resolution n IF Synthesizer System Integer-N IF PLL Programmable Charge Pump Current Levels Programmable Frequencies n Supports Various Reference Oscillator Frequencies 19.20/19.68 MHz n Fast Lock Time: 500 µs n Low Current Consumption 17 m A at 2.8 V n 2.7 V to 3.3 V Operation n Digital Filtered Lock Detect Output n Hardware and Software Power Down Control Applications n Korean PCS CDMA Systems with GPS n...