View AN7280S_118011.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

ICs for FM/AM Tuner
AN7280S
FM Front-end IC for Car Radio
s Overview
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).
Unit : mm 0.4 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 1.50.2
0.40.25
s 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
0.10.1
1.27
0.3
5.40.3 7.70.3
20-Lead SOP Package (SOP020-P-0300B)
s Block Diagram
GND 20 19 18 17 16 15 14 13 12 11
ADX
IF Amp. Mixer
VREG Buffer AGC Amp.
Buffer
SSC Det.
OSC
1
2
3
4
5
6
7
8 GND
9
10 VCC
0.15 0.65
12.60.3
AN7280S
s Absolute Maximum Ratings (Ta=25C)
Parameter Supply Voltage Supply Current Power Dissipation Operating Ambient Temperature Storage Temperature Symbol VCC ICC PD Topr Tstg Rating 9.2 50 460 -40 ~ + 85 -55 ~ + 150
ICs for FM/AM Tuner
Unit V mA mW C C
s Recommended Operating Range (Ta=25C)
Parameter Operating Supply Voltage Range Symbol VCC Range 6.8V ~ 9.2V
s Electrical Characteristics (Ta=25C)
Parameter S/N Ratio Local Oscillation Level IF Output Level AGC Level (L) AGC Level (H) Symbol NOUT VOSC VOUT VAGC (L) VAGC (H) Condition VCC= 8V, Vin=17dBNo modulation However, S= output at 400Hz, 30%modulation VCC= 8V, fOSC= 108.7MHz Measured by Pin4, No signal input VCC= 8V, Vin= 51dB VCC= 8V, Vin= 67dB VCC= 8V, Vin= 53dB 6 min. 22 219 41 typ. 30 384 58 0.05 6.5 435 82 0.5 max. Unit dB mV mV V V
s Characteristics Curve
Level * Diagram
50 43.5 (max.) 40 Level (dB) 0 30 20 13.5 AFOUT (dB) 10 0 8.5 -40 24.5 16.0 (min.) -20 Vin (dBV) VCC=8V fin=98MHz Mod.=22.5kHz fm=1kHz IF : AN7256 400Hz HPF ON 20 15 10 5 0 -5 -10 -15 -80 0 20 40 Vin (dBV) 60 80 88 90 92 94 96 98 100 102 104 106 108 fin (MHz) Residual Noise Practical Sensitivity (S/N=30dB)
Input/Output Characteristics
Frequency Change
VCC=8V fin=1kHz Mod.=22.5kHz IF : AN7256
Limiting Sensitivity
IFT IN Mix. 080 MS3
0.01F IF-Amp. 330
IF OUT
-60
ICs for FM/AM Tuner
AN7280S
AGC ON Level
110 VCC= 8V fin = 18MHz Radj. is Piny external resistance (AGC Start Point Variable) AGC ON Level (dBV)
IF-Amp. Gain Adjustment
Input 40 100 IF Amp. 13 f=10.7MHz Output 330
Amp. Gain Adjustment with AGC
VCC = 8V fin = 98MHz No Adjustment Pin7 = HIGH
110
100
90
Vin (dBV)
Gain (dB)
30
90 80
Radj.= 0
80
Pin9 = High
20
27dB 70 60
70
10 50 0 0
Radj.=
60
Pin9 = Low
50 0 1 1.4 1.8 2.2
in
0
1k
10K
4 (V)
0
1k
10K
Pin13 Adjusting Resistance ()
Pin7 Vcont
Pin6 Adjusting Resistance ()
Supply Voltage Change
Supply Voltage Dependence
No Input 35 11 10 5 4 Vref 15 10 Itot Vref (V) 3 2 1 0 12 AGC OUT Vt (V) 9
Supply Voltage Dependence
No Input
110 100 Vin (dBV) Local Oscillation Level 30 25 Itot (mA ) 60 AGC ON Level 50 20
5 Vt SSC ON Level (V) 4 3 SSC ON Level 2 1 0
8 7 6 5 4
20 10 0 6
Practical Sensitivity Limiting Sensitivity 7 8 VCC (V) 9 10 5 0
0
2
4
6 VCC (V)
8
10
5
6
7
8
9
10
11
12
VCC (V)
Temperature Characteristics
80 70 60 4 Vin (dBV) 10 IC for IF/DET is normal temperature 8 6
Total Gain Temperature Characteristics
Mixer+IF-Amp. VCC= 8V 105 100 95 90 Vin (dBV) 85 80 75 70 65 60 -40 -20 0 20 40 60 80 100 55
AGC Start Point Temperature Characteristics
Pin7=1V Pin6=GND Pin9=OPEN
50 40 30 20 10
AGC ON Level (max. Gain)
Total Gain (dB)
2 0 -2 -4 0dB= 43.5dB
Pin7=HIGH Pin6=GND Pin9=OPEN Pin7=HIGH Pin6=OPEN Pin9=5V Pin7=HIGH Pin6=OPEN Pin9=OPEN -40 -20 0 20 40 60 80 100
Practical Sensitivity (S/N=30dB) Limiting Sensitivity 0 20 40 60 80 100
-6 -8 -10
0 -60 -40 -20
Ta (C)
Ta (C)
Ta (C)
AN7280S
IF Amp. Output Saturation Level Temperature Characteristics
5 VCC=8V 4 IF Amp. Output Saturation Level (dB) 3 2 1 0 -1 -2 -3 -4 -5 -40 -20 0 20 40 60 80 100 0 -40 -20 0 20 40 60 80 100 1 Pino Voltage (V) 3 4 5 SSC Input Pin 9
ICs for FM/AM Tuner
SSC ON Level Temperature Characteristics
2
Ta (C)
Ta (C)
s Application Circuit
VCC 820 ANT 82k
0.01F 100k
0.001F MA551
18pF
KVC-1340 15pF
18pF
3SK1311
22
KVC-1340
12pF
100k
330
0.001F
100k
Produced by MATSUSHITA IFT : ZIF-5EF021B
330 470 C-F
4pF 0.01F
1k
0.01F
0.01F
To IF 12 11
20 100k
19
18 RF IN
17
16
15
14 IF IN
13
GND PIN D AGC
Pass Mix Mix Con. OUT OUT
E 1 12pF
B 2
AGC Gain 2 Loop Pass OSC C OUT AGC Adj IN GND SSC 3
56pF 0.01F 0.001F
AN7280S
4 5
IF Pass IF Gain Con. OUT Adj
VCC 10
0.01F
6
7 180k
8
9
+ -
120k KVC-1340 3pF VT
1F
0.01F
56pF
5V 5V 0V Control Voltage At Search
At Normal 0V
ICs for FM/AM Tuner
s Pin Descriptions
Pin No. 1 Pin Name OSC Emitter Description Local oscillation transistor emitter pin 2 1 2 OSC Base Local oscillation transistor base pin
AN7280S
Equivalent Circuit
Vref
5V
3
OSC By-pass
Vref by-pass pin for mixer,OSC buffer,OSC section
+ -
3
Vref
4
OSC Buffer Output
Pin for output OSC signal to pre-scaler 4
750
VCC .70A
5
Level Detection Output
AGC signal output pin for RF-Amp. secondary gate
5
6
AGC- Amp. Gain Adjustment
Pin for adjusting AGC Amp. gain by external resistance
6
5.6k
7
Control Signal Input
Pin for adjusting AGC-Amp. gain through input of control signal from IF section
1.5k 1.5V
7
8
GND
Vref
9
SSC Input
Pin for adjusting AGC-Amp. gain through input of control signal from microcomputer
70k 39k
9
10
VCC
AN7280S
s Pin Descriptions (Cont.)
Pin No. Pin Name Description
ICs for FM/AM Tuner
Equivalent Circuit
11
IF-Amp.
IF-Amp. output pin
3k
240
11
ZOUT.300
12
IF-Amp. By-pass
IF-Amp. by-pass pin
330
12 14
14
IF-Amp. Input
IF-Amp. input pin
13
IF-Amp. Gain Adjustment
Pin for adjusting IF-Amp. gain by external resistance
13
340 12k
15 Mix. Output 16 Mixer output pin
15
16
2.2k
17
Mix. By-pass
Mixer by-pass pin 17 18
2.2k
18
Mix. Input
Mixer input pin
VCC
19
ADX Output
PIN diode driver output pin Determine maximum current to PIN diode by Pin19 external resistance value.
19
20
GND
Oscillator GND
ICs for FM/AM Tuner
s Operational Description * Loop AGC
AN7280S
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. Mixer IF-Amp. 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 3
AGC Output AGC-Adj 5 6 R2
Vcont IN 7
SSC IN 9
about 4.7V VAGC
R1 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.

▲Up To Search▲

Price & Availability of AN7280S

	To Download AN7280S Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .