Texas Instruments LMX2337MX

Description
The LMX2335, LMX2336, and LMX2337 are monolithic, integrated dual frequency synthesizers with two high-frequency prescalers. They are designed for applications requiring two RF phase-lock loops and are fabricated using National's ABIC IV silicon BICMOS process.
The LMX2335/36/37 contain two dual modulus prescalers, with a selectable 64/65 or 128/129 prescaler for each RF synthesizer. They also include a second reference divider chain for improved system noise. Employing a digital phase-locked loop technique, combined with a high-quality reference oscillator and loop filters, the LMX2335/36/37 provide tuning voltages for voltage-controlled oscillators to generate stable, low-noise RF local oscillator signals.
Serial data is transferred into the LMX2335/36/37 via a three-wire interface (Data, Enable, Clock). Supply voltage can range from 2.7V to 5.5V. The LMX2335/36/37 feature low current consumption: LMX2335/37 -10 mA at 3V, LMX2336 -13 mA at 3V. They are available in both JEDEC SO and TSSOP 16-pin surface mount plastic packages (LMX2335/37) and a TSSOP 20-pin surface mount plastic package (LMX2336).

Features
2.7V to 5.5V operation
Low current consumption
Selectable powerdown mode: loc 1 μA (typ)
Dual modulus prescaler: 64/65 or 128/129
Selectable charge pump TRI-STATE mode
Selectable charge pump current levels
Selectable FastLock™ mode

Applications
Cellular telephone systems (AMPS, ETACS, RCR-27)
Cordless telephone systems (DECT, ISM, PHS. CT-1 )
Personal Communication Systems (DCS-1800, PCN-1900)
Dual Mode PCS phones
CATV
Other wireless communication systems