TDA7427A Datasheet, PDF (1/21 Pages) STMicroelectronics – AM-FM RADIO FREQUENCY SYNTHESIZER AND IF COUNTER

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TDA7427A
AM-FM RADIO FREQUENCY SYNTHESIZER
AND IF COUNTER
ON-CHIP REFERENCE OSCILLATOR AND
PROGRAMMABLE IF COUNTER
VHF INPUT AND PRECOUNTER FOR FRE-
QUENCIES UP TO 290MHz (SUITABLE FOR
DAB APPLICATION)
HF INPUT FOR FREQUENCIES UP TO
64MHz (SHORT WAVE BAND)
IN-LOCK DETECTOR FOR SEARCH/STOP
STATION FUNCTION
STAND-BY MODE FOR LOW POWER CON-
SUMPTION
HIGH CURRENT SOURCE FOR 0.5ms
LOCK-IN TIME
DIGITAL PORT EXTENSION WITH SIX OUT-
PUTS FOR FLEXIBILITY IN APPLICATION
FULLY PROGRAMMABLE BY I²C BUS
DESCRIPTION
The TDA7427A is a PLL frequency synthesizer
TSSOP28
SO28
ORDERING NUMBERS: TDA7427AAD (TSSOP28)
TDA7427AAD1 (SO28)
with an additional IF counting system that per-
forms all the functions needed in a complete PLL
radio tuning system for conventional and high
speed RDS tuners. The device has dedicated out-
puts for IN-LOCK detection and Search/Stop sta-
tion.
BLOCK DIAGRAM
24
FM_IN
19
HFREF
25
AM_IN
SWITCH
AM/FM
PRECOUNTER
:32/33
SWITCH
SWM/DIR
5 BIT PROG.
COUNTER
SWITCH
SWM/DIR
9
OSCIN
10
OSCOUT
REF
OSCILLATOR
ADDR
SCL
SDA
20
12 _{I2C BUS}
13 ^INTERFACE
VDD2
VDD1
GNDDIG
IF_AM
IF_FM
27
SUPPLY
21
&
POWER-ON
22 RESET
14 BIT PROG
COUNTER
14
SWITCH
15
AM/FM
16 BIT PROG
COUNTER
11 BIT PROG
COUNTER
TIMER
CONTROL
11-21 BIT PROG COUNTER
D95AU372D
INLOCK
DETECTOR
PHASE
COMP
CHARGE
PUMP
SWITCH ¹⁷
OUT
2
3
SWITCH
1
LP1/LP2
DOUT1/INLOCK
LP_HC
LP_AM
LP_FM
-
28
LP_OUT
+
VDD1
4
VREF
26
GNDAN
TEST
LOGIC
PORT EXTENSION
16
SSTOP
18
5
6
7
8
DOUT2 DOUT3 DOUT4 DOUT5 DOUT6
July 1998
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