LV25300M_0711 Datasheet, PDF (3/4 Pages) Sanyo Semicon Device – 1-chip Tuner IC

LV25300M
Bus control circuit Automatic adjustment
Switching control
• AM/FM reception switching
• AM/FM RF AGC sensitivity setting: 4 bits
• FM keyed AGC control: 4 bits
• AM/FM RF tuning DAC (9 bits × 2)
• AM/FM SD control ON/OFF
• AM/FM IF counter output control ON/OFF
• AM oscillator 1 divider setting
• SEEK/receive mode switching
• FM ANT tuning circuit fc control
• FM RF tuning circuit fc control
• AM/FM IF gain adjustment
• FM/AM W-AGC sensitivity adjustment
• FM/AM N-AGC sensitivity adjustment
• FM S-meter shift
• AM/FM SD sensitivity setting
• NULL adjustment
• AFC band width
Connection to CDSP300 (interface)
• AM/FM IF output (450kHz)
• AM/FM S-meter output, AC/DC 2 systems
• AM-NC gate trigger output
Diversity
• Noise amplifier, noise, and AGC circuits
• Noise density coefficient circuit
• Antenna selection output
• Generating a signal for the antenna switching frequency
and positioning antenna
• Weak electric field detection and antenna positioning
Block Diagram
FM ANT tuner circuit
FM RF AMP circuit
FM RF tuner circuit
AM ANT circuit
AM RF AMP circuit
BPF
MIX
COIL
CF 10.7MHz
CF 10.7MHz
AM TRANS
CF 10.7MHz
80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64
63 62
61
FE
1
AM block
60
AM-NC
2
ANT-D
FM
AM
ANT-D
4.9V REG
AM
1stAMP
NC STOP
TRIG
59
1st
1st
3
MIX
MIX
58
NOIZE NOIZE
AMP
AGC
4
RF
RF
57
5
Keyed
AGC
N AGC
W
AGC
W
AGC
M AGC
SD
56
S-METER
IF AGC
AM
2ndMIX
COIL
tuner
circuit
6
7
8
PLL
OSC
FM
Lo/DX
AM
Lo/DX
DAC block
AM detector
2ndIFAMP
55
54
low cut
AMP
DETECTET
Differential Differential
AMP2
AMP1
53
9
NMOS Tr
ECL
1/4, 1/6
POWER ON
RESET
52
10
1/8, 1/10
BUS-
51
swallow
LPF
11
counter ^{IF COUNTER}
IN 1
IN 2
IN 3-1
12
P-CTR
6/8bit AD
converter
IN 3-2
IN 3-3
13
phase
det
R-CTR
IN 3-4
14
charge
pump
BUS
DAC
CIRCUIT
FM IF
50
FM
S-METER
Limiter
49
1stAMP
(DC/AC)
AMP
48
SD
2ndMIX
47
15
Diversity block
16
ANT selector
17
CURRENT
DRIVER
18
COUNTER
Time constant
generator
19
LOGIC
DIVIDER
20
MAIN FIX
CIRCUIT
NOIZE AMP
3V REG
XTAL
OSC
46
AFC
AUDIO
MUTE
DETECTER
CIRCUIT CIRCUIT
45
44
2.7V REG
43
450kHz
42
450kHz
OUTPUT_BUFFER
41
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
XTAL 10.25MHz
CF 450kHz
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