Description

The SP5848 is a dual PLL frequency synthesizer controlled by a 3-wire bus optimised for application in double conversion tuners.

Each synthesiser loop within the SP5848 is independently addressable and contains an RF programmable divider, phase/frequency detector and charge pump/loop amplifier section; a common reference frequency oscillator and divider chain is provided, whose ratios for each loop are independently programmable.

Features

● Dual independent PLL frequency synthesisers in a single package, optimised for double conversion cable tuners, offering improved application

● 2.2GHz up-synthesiser optimised for low phase noise up to comparison frequencies of 4MHz

● 1.3GHz down-synthesiser optimised for low phase noise AND small step size

● Common reference oscillator and divider with independently selectable ratios for each synthesiser

● 10:1 programmable charge pump current ratio in up synthesiser

● 3-Wire bus programmable, each synthesiser indepently addressable

● Low power consumption, typ 100mW at 5V

● ESD protection, (Normal ESD handling procedures should be observed)

Applications

● TV, VCR, and cable tuning systems