The LMX2310/1/2/3U are high performance frequency synthesizers. The LMX2310/1/2U use a selectable, dual modulus 32/33 and 16/17 prescaler. The LMX2313U uses a selectable, dual modulus 16/17 and 8/9 prescaler. The device, when combined with a high quality reference oscillator and a voltage controlled oscillator, generates very stable, low noise local oscillator signals for up and down conversion in wireless communication devices. Serial data is transferred into LMX2310/1/2/3U via a threewire interface (Data, Enable, Clock) that can be directly interfaced with low voltage baseband processors. Supply voltage can range from 2.7V to 5.5V. LMX2310U features very low current consumption, typically 2.3 mA at 3.0V. The LMX2310/1/2/3U are manufactured using National's 0.5 ABiC V silicon BiCMOS process and is available in 20-pin CSP packages.