Panasonic AN7280S Fm front-end ic for car radio Datasheet

ICs for FM/AM Tuner
AN7280S
FM Front-end IC for Car Radio
■ Overview
Unit : mm
5.4±0.3
7.7±0.3
0.15
0.65
0.3
12.6±0.3
0.4±0.25
0.1±0.1
1.27
■ Features
• High sensitivity, high S/N ratio
• Good IM characteristics at strong input
• Available for two loop AGC (keyed AGC)
• Pre IF amp. gain variable
• PIN diode driver (ADX) built-in
20
19
18
17
16
15
14
13
12
11
1
2
3
4
5
6
7
8
9
10
1.5±0.2
0.4
The AN7280S is an FM front-end IC designed for DTS
except RF amp. of car radio. It features built-in local oscillation frequency buffer output, PIN diode driver for antenna damping and SSC (search stop control).
20-Lead SOP Package (SOP020-P-0300B)
■ Block Diagram
GND
20
19
18
17
16
15
14
13
12
11
IF Amp.
ADX
Mixer
VREG
Buffer
AGC Amp.
Buffer
SSC
OSC
1
Det.
2
3
4
5
6
7
8
GND
9
10
VCC
ICs for FM/AM Tuner
AN7280S
■ Absolute Maximum Ratings (Ta=25˚C)
Symbol
Rating
Supply Voltage
Parameter
VCC
9.2
Unit
V
Supply Current
ICC
50
mA
Power Dissipation
PD
460
mW
Operating Ambient Temperature
Topr
–40 ~ + 85
˚C
Storage Temperature
Tstg
–55 ~ + 150
˚C
■ Recommended Operating Range (Ta=25˚C)
Parameter
Symbol
Range
Operating Supply Voltage Range
VCC
6.8V ~ 9.2V
■ Electrical Characteristics (Ta=25˚C)
Parameter
Symbol
S/N Ratio
NOUT
Local Oscillation Level
VOSC
min.
Condition
VCC= 8V, Vin=17dBµNo modulation
However, S= output at 400Hz, 30%modulation
VCC= 8V, fOSC= 108.7MHz
Measured by Pin4, No signal input
VCC= 8V, Vin= 51dBµ
IF Output Level
VOUT
AGC Level (L)
VAGC (L)
VCC= 8V, Vin= 67dBµ
AGC Level (H)
VAGC (H)
VCC= 8V, Vin= 53dBµ
typ.
max.
22
30
219
384
41
6
Unit
dB
435
mV
58
82
mV
0.05
0.5
V
6.5
V
■ Characteristics Curve
Level · Diagram
Input/Output Characteristics
Frequency Change
50
40
20
0
30
24.5
10
–20
13.5
0
0.01µF
IFT
IN
IF–Amp.
Mix.
080
MS3
IF
OUT
Vin (dBµV)
8.5
10
VCC=8V
fin=1kHz
Mod.=22.5kHz
IF : AN7256
15
16.0 (min.)
20
AFOUT (dB)
Level (dB)
fm=1kHz
IF : AN7256
400Hz HPF ON
VCC=8V
fin=98MHz
Mod.=22.5kHz
43.5 (max.)
–40
–60
5
Practical Sensitivity (S/N=30dB)
Limiting Sensitivity
0
–5
–10
Residual Noise
–15
330Ω
–80
0
20
40
Vin (dBµV)
60
80
88 90 92 94 96 98 100 102 104 106 108
fin (MHz)
ICs for FM/AM Tuner
AN7280S
Amp. Gain Adjustment
with AGC
AGC ON Level
IF-Amp. Gain Adjustment
110
IF Amp.
13
f=10.7MHz
Input
Output
330Ω
VCC= 8V
fin = 18MHz
Radj. is Piny external resistance
(AGC Start Point Variable)
110
40
VCC = 8V
fin = 98MHz No Adjustment
Pin7 = HIGH
100
20
90
AGC ON Level (dBµV)
30
Vin (dBµV)
Gain (dB)
100
Radj.= 0Ω
80
27dB
70
90
Pin9 =
High
80
70
60
Radj.= ∞
10
Pin9 = Low
60
50
0
0
1k
0
∞
10K
50
0
1
1.4
1.8
2.2
Pin7 Vcont
Pin13 Adjusting Resistance (Ω)
in
4
0
∞
10K
Pin6 Adjusting Resistance (Ω)
Supply Voltage Dependence
Supply Voltage Change
1k
(V)
Supply Voltage Dependence
No Input
No Input
35
11
30
10
60
AGC ON Level
50
Vref
Itot
3
15
20
Practical Sensitivity
10
Limiting Sensitivity
0
4
20
6
7
8
9
1
5
0
12
4
2
4
6
10
SSC ON Level
6
5
6
7
8
10
100
6
95
4
90
2
85
30
20
Practical Sensitivity (S/N=30dB)
10
0
–60 –40 –20
Limiting Sensitivity
0
20
40
Ta (˚C)
60
80 100
0
Vin (dBµV)
40
Total Gain (dB)
Vin (dBµV)
AGC ON Level (max. Gain)
0dB= 43.5dB
–2
–6
65
–8
60
0
20
40 60
Ta (˚C)
0
80 100
Pin7=HIGH
Pin6=GND
Pin9=OPEN
75
70
–40 –20
12
Pin7=1V
Pin6=GND
Pin9=OPEN
80
–4
–10
11
105
60
50
10
AGC Start Point
Temperature Characteristics
Mixer+IF–Amp.
VCC= 8V
8
9
VCC (V)
Total Gain
Temperature Characteristics
IC for IF/DET
is normal temperature
2
1
VCC (V)
Temperature Characteristics
70
8
3
7
5
0
4
8
2
VCC (V)
80
Vt
10
0
10
5
9
55
Pin7=HIGH
Pin6=OPEN
Pin9=5V
Pin7=HIGH
Pin6=OPEN
Pin9=OPEN
–40 –20
0
20
40 60
Ta (˚C)
80 100
SSC ON Level (V)
Itot (mA )
Vin (dBµV)
5
25
Vref (V)
Local Oscillation Level
100
AGC OUT Vt (V)
110
ICs for FM/AM Tuner
AN7280S
IF Amp. Output Saturation Level
Temperature Characteristics
SSC ON Level
Temperature Characteristics
5
5
VCC=8V
SSC Input Pin
9
3
4
2
Pino Voltage (V)
IF Amp. Output Saturation Level (dB)
4
1
0
–1
3
2
–2
–3
1
–4
–5
–40 –20
0
20
40 60
0
80 100
–40 –20
0
20
Ta (˚C)
40 60
80 100
Ta (˚C)
■ Application Circuit
VCC
0.01µF
KVC–1340
12pF
22Ω
330Ω
Produced by MATSUSHITA
IFT : ZIF–5EF021B
330Ω
19
18
56pF
3pF
KVC–1340
14
Pass Mix Mix
Con. OUT OUT
IF
IN
AN7280S
13
To IF
12
11
IF Pass IF
Gain Con. OUT
Adj
AGC
Gain 2 Loop
Pass OSC
C OUT AGC Adj
IN GND SSC
3
4
5
6
7
8
9
VCC
10
180kΩ
+
–
120kΩ
VT
15
0.01µF
2
16
0.01µF
B
1
RF
IN
56pF
0.01µF
E
12pF
100kΩ
GND PIN
D
AGC
17
0.001µF
20
0.01µF
0.01µF
0.01µF
4pF
1kΩ
C–F
470Ω
100kΩ
100kΩ
MA551
3SK1311
100kΩ
18pF
KVC–1340
0.001µF
18pF
15pF
0.001µF
82kΩ
820Ω
ANT
1µF
5V 5V
0V
Control
Voltage
At Search
At Normal
0V
ICs for FM/AM Tuner
AN7280S
■ Pin Descriptions
Pin Name
Pin No.
Description
Equivalent Circuit
Vref
1
OSC Emitter
Local oscillation transistor emitter pin
2
1
2
OSC Base
Local oscillation transistor base pin
3
OSC By-pass
Vref by-pass pin for mixer,OSC buffer,OSC
section
5V
+
–
3
Vref
4
OSC Buffer Output
Pin for output OSC signal to pre-scaler
4
750Ω
VCC
.70µA
5
Level Detection Output
AGC signal output pin for RF-Amp.
secondary gate
6
AGC– Amp. Gain Adjustment
Pin for adjusting AGC Amp. gain by
external resistance
5
6
5.6kΩ
7
Control Signal Input
8
GND
Pin for adjusting AGC-Amp. gain through
input of control signal from IF section
1.5kΩ
1.5V
Vref
9
SSC Input
Pin for adjusting AGC-Amp. gain through
input of control signal from microcomputer
70kΩ
39kΩ
10
VCC
9
7
ICs for FM/AM Tuner
AN7280S
■ Pin Descriptions (Cont.)
11
Description
Pin Name
Pin No.
IF-Amp.
Equivalent Circuit
IF-Amp. output pin
240Ω
11
3kΩ
ZOUT.300Ω
12
IF-Amp. By-pass
IF-Amp. by-pass pin
12
330Ω
14
14
IF-Amp. Input
IF-Amp. input pin
13
IF-Amp. Gain Adjustment
Pin for adjusting IF-Amp. gain by external
resistance
13
12kΩ
15
15
Mix. Output
Mixer output pin
Mix. By-pass
Mixer by-pass pin
340Ω
16
16
2.2kΩ
17
17
2.2kΩ
18
18
Mix. Input
Mixer input pin
VCC
19
20
ADX Output
GND
PIN diode driver output pin
Determine maximum current to PIN diode
by Pin19 external resistance value.
Oscillator GND
19
ICs for FM/AM Tuner
AN7280S
■ Operational Description
• Loop AGC
The AN7280S uses 2Loop AGC for AGC circuit. 2Loop AGC controls AGC output by using mixer output (IFT first side)
signal and FM–IF control voltage (level meter output), which is a very favorable system for disturbance characteristics,
etc.
IFT
RF–Amp.
IF–Amp.
Mixer
FM–IF
To N.C.
Control Voltage Output
AGC
Amp.
AGC
Det.
• AGC start point (Mixer input level at V
AGC < 3V) changes in proportion to Pin6 external resistance (following R1) , Pin
7 applied voltage (Determine IF control voltage by R2, R3 resistance division) SSC ON/OFF
· Variable width at R 1 28dB (however, V7 ≥3V, V9 = 0V)
· Variable width at R7 40dB (however, R1= ∞, V9= 0V)
· Variable width at R9 10dB (however, R1= ∞, V7 ≥3V)
VREF
AGC Output AGC–Adj
3
5
6
Vcont IN
SSC IN
7
9
R2
about 4.7V
R1
VAGC
R3
from microcomputer
FM–IF
Control voltage
• SSC
Change AGC start point by microcomputer control signal at seek/reception time.
Use at SSC ON ········V9 > 3.5V
Use at SSC OFF········V9 < 1.5V
* SSC is designed as precondition for switching operation at microcomputer control signal.
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