GENERAL DESCRIPTION

The UMA1015AM is a low-power dual frequency synthesizer for radio communications which operates in the 50 to 1100 MHz frequency range. Each synthesizer consists of a fully programmable main divider, a phase and frequency detector and a charge pump. There is a fully programmable reference divider common to both synthesizers which operates up to 35 MHz.

FEATURES

• Two fully programmable RF dividers up to 1.1 GHz

• Fully programmable reference divider up to 35 MHz

• 2 : 1 or 1 : 1 ratio of selectable reference frequencies

• Fast three-line serial bus interface

• Adjustable phase comparator gain

• Programmable out-of-lock indication for both loops

• On-chip voltage doubler

• Low current consumption from 3 V supply

• Separate power-down mode for each synthesizer

• Up to 4 open-drain output ports

• Crystal input frequency signal inverted and buffered output on separate pin.

APPLICATIONS

• Cordless telephone

• Hand-held mobile radio.