TDA7421 Datasheet, PDF (1/38 Pages) STMicroelectronics – AM/FM TUNER FOR CAR RADIO AND Hi-Fi APPLICATIONS

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TDA7421
AM/FM TUNER FOR CAR RADIO
AND Hi-Fi APPLICATIONS
FRONT-END FOR AM/FM RECEIVERS
UP-CONVERSION ARCHITECTURE FOR AM
HIGH SPEED PLL WITH INLOCK DETECTOR
FOR OPTIMIZED RDS APPLICATIONS
SINGLE FREQUENCY REFERENCE FOR AM/FM
AM/FM STATION DETECTOR
µP-CONTROLLED COMPENSATION OF EX-
TERNAL COMPONENTS SPREAD
ADJUSTABLE AUDIO MUTE
FULLY PROGRAMMABLE BY I²C BUS
ADVANCED BICMOS TECHNOLOGY
GENERAL DESCRIPTION
The TDA7421 is a high performance tuner circuit
that integrates AM/FM sections, IF counter and
PLL synthesizer on a single chip.
Use of BICMOS technology allows the implemen-
tation of tuning functions with a minimum of exter-
nal components.
Value spread of external components can be fully
PINS CONNECTION
TQFP64
ORDERING NUMBER: TDA7421
compensated by means of on-chip electrical ad-
justment controlled by external µP.
The Automatic Gain Control (AGC) operates on
different sensitivities and bandwidths in order to
improve sensitivity and dynamic range. I²C bus
allows to control selected functions of the tuner
(AGC and amplifiers gain, PLL and counters op-
eration modes).
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
D96AU546A
June 1998
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