描述 Description

The AFE8220 implements the intermediate frequency (IF) sampling and processing functions of a digital radio receiver system.It is designed to be used with TI?s digital radio baseband processors and AM/FM tuners.The AFE8220 can also be programmed by the baseband processor for use in conventional AM/FM and digital radio.This unit includes two IF inputs with associated filtering and digital processing circuitry. The receive circuit oversamples the radio tuner IF output to reduce noise and improve dynamic range.The IF analog-to-digital converter (ADC) oversamples the IF input at rates up to 75 MHz.The AFE8220 then digitally mixes, filters, and decimates the signal to provide in-phase (I) and quadrature (Q) output signals to the baseband processor.A clock oscillator circuit is provided that can be used with an appropriate third-overtone crystal and external tank circuit to generate the sampling clock for the IF ADCs. The AFE8220 also includes a real-time clock and associated low-power oscillator circuit.Two auxiliary digital-to-analog converters (DACs) are included for system control functions. Other features include eight general-purpose input/output (GPIO) lines and programmable interrupt generators. The AFE8220 is available in a TQFP-100 (14 mm × 14 mm) package and uses a 3.3-V and a 1.8-V power supply.An onboard voltage regulator is included to optionally generate the 1.8-V digital supply for the AFE8220.

特性 Features

·Qualified for Automotive Applications
·Two Intermediate Frequency (IF)Analog-to-Digital Converters (ADCs)
·Two 12-Bit Auxiliary Digital-to-AnalogConverters (DACs)
·Integrated IF Digital Processing Core
·Integrated Circuitry for Third-OvertoneMaster Clock Oscillator
·Wakeup Circuit/Real-Time Clock With SeparateCrystal Oscillator
·Flexible Data Interface Optimized for TMSFamily of Digital Baseband Processors
·Pin-Selectable SPI? and I2C? ControlInterfaces
·3.3-V/1.8-V Supply (Integrated RegulatorAvailable to Optionally Generate 1.8-V Supply)
·TQFP-100 PowerPAD? Package
·APPLICATIONS ·IF-Sampled AM/FM Radio
·Hybrid Digital (HD) Digital Audio Broadcasting(DAB) Digital Radio

PowerPAD is a trademark of Texas Instruments. SPI is a trademark of Motorola, Inc. I2C is a trademark of NXP Semiconductors. All other trademarks are the property of their respective owners.