AFE8221IRFPQ1 Datasheet PDF - TI

The AFE8221 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 AFE8221 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 AFE8221 then digitally mixes, filters, and decimates the signal to provide I and 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 AFE8221 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. An 8-bit auxiliary ADC and input multiplexer (MUX) can be used for system diagnostic functions. Other features include 12 general-purpose input/output (GPIO) lines, programmable interrupt generators, and an I2C master for communication between the AFE and the tuner(s).

●The AFE8221 is available in a TQFP-144 (20 mm × 20 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 AFE8221.