TDA7421N Datasheet, PDF (1/38 Pages) STMicroelectronics – AM/FM TUNER FOR CAR RADIO AND HI-FI APPLICATIONS

TDA7421N
AM/FM TUNER FOR CAR RADIO AND HI-FI APPLICATIONS
PRELIMINARY DATA
s HIGH PERFORMANCE FRONT-END IC FOR
AM/FM RECEIVERS
s FULLY INTEGRATED HIGH-SPEED PLL FOR
OPTIMIZED RDS APPLICATIONS
s FM MPX/AM AUDIO OUTPUT, 450kHz AM IF
OUTPUT FOR STEREO AM APPLICATIONS
s AM DOUBLE CONVERSION ARCHITECTURE
s AM/FM STATION DETECTOR AND DIGITAL
IF-COUNTER
s SINGLE FREQUENCY REFERENCE FOR
BOTH AM AND FM
s FULL ELECTRICAL ADJUSTMENT
s I²C-BUS PROGRAMMABLE
DESCRIPTION
The TDA7421N is a high-performance tuner circuit
which integrates AM and FM sections, PLL frequency
sinthesizer and IF counter on a single chip.
Use of BICMOS technology allows the implementa-
tion of tuning functions with a minimum of external
components.Value spread of external components
can be fully compensated by means of on-chip elec-
TQFP64
ORDERING NUMBER: TDA7421N
trical adjustment controlled by external µP.
The FM quality detection circuit, in conjunction with
the digital IF counter, enables the stop-station func-
tion in “seek” mode and MPX mute during reception.
The combination of programmable level detector and
IF counter allows reliable AM stop-station perfor-
mance.
The Automatic Gain Control (AGC) operates on dif-
ferent signal bandwidths in order to optimize sensitiv-
ity and dynamic range.
I²C-bus controls functions such as AGC, amplifier
gains, PLL and counter settings.
PIN CONNECTIONS
AM MIX1 IN -
AM MIX1 IN +
FM MIX IN -
FM MIX IN +
FM RF AGC IN
FM AGC OUT
RF GND
VCO B
VCO E
OSC GND
XTAL D
XTAL G
OSC VCC
FM ANT ADJ
FM RF ADJ
PLL VCC
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FM IF AMP2 OUT
IF1 VCC
FM LIM IN +
FM LIM IN -
IF1 GND
FM BW TC
FM MUTE DRIVE
FM SMETER AM SMETER
FM DET ADJ
FM SD AM SD
AUDIO OUT
FM QUAD+
FM QUAD-
IF2 VCC
AM IF2 IN
AM REF
AM BPF
D98AU909
August 2000
This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
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