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 MN1A construction so giving a step size equal to the loop comparison frequency and no prescaler phase noise degradation over the full 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 for a second frequency synthesiser. The synthesiser is controlled via an 12C 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 1·3 GHz 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 4 MHz

? No RF Prescaler

? Selectable Reference/Comparison Frequency Output

? Four Selectable I2C Addresses

? I2C Fast Mode Compliant with 3·3V and 5V Logic Levels

? Four Switching Ports

? Functional Replacement for SP5659 (except ADC)

? Pin Compatible with SP5655

? Power Consumption 120mW with VCC= 5·5V, all Ports off

? ESD Protection 2kV min., MIL-STD-883B Method 3015

Cat.1 (Normal ESD handling procedures should be observed)

Applications

? Digital Satellite, Cable and Terrestrial Tuning Systems

? Communications Systems