描述 Description

The SP5730 is a single chip frequency synthesiser designed for tuning systems up to 1.3GHz and is optimised for digital terrestrial applications.

The RF preamplifier interfaces direct with the RF programmable divider, which is of MN+A construction so giving a step size equal to the loop comparison frequency and no prescaler phase noise degradation over the RF operating range.

The comparison frequency is obtained either from an on-chip crystal controlled oscillator, or from an external source. The oscillator frequency, Fref, or phase comparator frequency, Fcomp, can be switched to the REF/COMP output providing a reference frequency for a second frequency synthesiser.

The synthesiser is controlled via an I2C bus and is fast mode compliant. It can be hard wired to respond to one of four addresses to enable two or more synthesisers to be used on a common bus.

The device contains four switching ports P0-P3.

特性 Features

● Complete 1.3GHz single chip system for Digital Terrestrial Television applications

● Selectable reference division ratio, compatible with (DTT) requirements

● Optimised for low phase noise, with comparison frequencies up to 4MHz

● No RF prescaler

● Selectable reference/comparison frequency output

● Four selectable I2C bus address

● I2C fast mode compliant and compatible with

3.3 and 5V logic levels

● Four switching ports

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

Applications

● Digital Satellite ,Cable and Terrestrial tuning systems

● Communications systems