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Ordering number : EN2276B
Monolithic Linear IC
LA1175, 1175M
FM Front End For Car Radio, Home Stereo Applications
Functions
· Double-balanced type MIX, PIN diode drive AGC output, MOS FET gate drive AGC output, keyed AGC, differential IF amplifier, buffer amplifier for oscillation, local oscillation.
Package Dimensions
unit: mm 3020A-SIP16
[LA1175]
Features
· By using the keyed AGC system, which is effective in improving the sensitivity suppression characteristic, in combination with the antenna damping AGC (PIN diode driver on chip) and MOS FET 2nd gate drive AGC, the intermodulation characteristic for a large undesired signal is greatly improved. It is also possible to use the keyed AGC system in combination with the antenna damping AGC or MOS FET 2nd gate drive AGC. · The temperature characteristic and noise figure are improved. The same supply voltage makes it easy to use the LA1175, 1175M.
SANYO: SIP16
unit: mm 3035A-MFP16
[LA1175M]
SANYO: MFP16
Specifications Maximum Ratings at Ta=25°C
Parameter Maximum supply voltage Allowable power dissipation Symbol VCC max Pd max Pins 8, 9 LA1175 : Ta70°C LA1175M : Ta70°C Mounted on PCB (bakelite) of 40mm×48mm×1.8mm Operating temperature Storage temperature Topr Tstg
2
Conditions Pins 4, 14
Ratings 9.5 15 460 435
Unit V V mW mW
20 to +70 40 to +125
°C °C
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TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN 93097HA (KT)/D0994JN/3237TA/8226KI, TS No.2276-1/14
LA1175, 1175M Operating Conditions at Ta=25°C
Parameter Recommended supply voltage Operating voltagerange Symbol VCC VCC op Conditions Pin 4, 8, 9, 14 Ratings 8 8 to 9 Unit V V
Electrical Characteristics at Ta=25°C, VCC=8V, See specified Test Circuit.
Parameter Current drain AGC high-level voltage AGC low-level voltage IF input resistance AGC control input Voltage gain Input limiting voltage AGC input voltage Saturation output voltage OSC BUFF output ANT damping drive current Symbol ICC VAGCH VAGCL RIN VCL7 VCL2 AV VINlim ViAGC VOUT VOSC BUFF IANT-D VIN=100dBµ, VAGC=7V VIN=100dBµ, VAGC=2V LA1175 : VIN=75dBµ LA1175M : VIN=75dBµ LA1175 : Referenced to VIN=110dBµ LA1175M : Referenced to VIN=110dBµ VAGC=2V LA1175 : VIN=110dBµ LA1175M : VIN=110dBµ 1k load VIN=100dBµ 1.1 99 97 81 80 67 110 100 105 4.5 Conditions Pins 4, 8, 9, 14 : no input VIN=0dBµ, VCL=4V VIN=100dBµ, VCL=4V 260 Ratings min 23.0 7.6 typ 28.0 7.9 0.2 330 0.25 1.6 102 100 88 87 74 114 113 109 6.0 8.0 0.7 400 0.5 2.1 105 103 95 94 81 max 33.0 Unit mA V V V V dBµ dBµ dBµ dBµ dBµ dBµ dBµ dBµ mA
Allowable power dissipation, Pd max mW
Ambient temperature, Ta °C
Allowable power dissipation, Pd max mW
Ambient temperature, Ta °C
No.2276-2/14
LA1175, 1175M Equivalent Circuit Block Diagram and Peripheral Circuit : LA1175
Unit (resistance : , capacitance : F) MIX output IFT 10mm YT-20577 (Mitsumi) 014-022 (Sumida) EKSC-30174FCU (Toko) OSC coil YT-30013 (Mitsumi) WIRE 0.8 inside dia. 6mm 4T air core MIX output (small-sized) 47K-074-124 (Sumida)
Equivalent Circuit Block Diagram and Peripheral Circuit : LA1175M
MIX output IFT 10mm YT-20577 (Mitsumi) 014-022 (Sumida) EKSC-30174FCU (Toko) OSC coil YT-30013 (Mitsumi) WIRE 0.8 inside dia. 6mm 4T air core MIX output (small-sized) 47K-074-124 (Sumida)
Unit (resistance : , capacitance : F) No.2276-3/14
LA1175, 1175M Internal Connection Diagram : LA1175
Unit (resistance : , capacitance : F)
Input/Output Characteristic
MIX input dBµ
Current drain, ICC mA
VAGC V IF output dBµ
Supply voltage, VCC V
No.2276-4/14
LA1175, 1175M
MIX BLOCK Input/Output Characteristic
MIX output dBµ
MIX input dBµ IF BLOCK Input/Output Characteristic
Unit (resistance : , capacitance : F)
IF output dBµ
IF input dBµ VAGC Input/Output Characteristic (AGC BLOCK)
ViANTD dBµ
IANTD mA VAGC V
Pin 10 input dBµ
f MHz
VAGC dBµ
Unit (resistance : , capacitance : F)
C 10 pF
No.2276-5/14
LA1175, 1175M
VAGC output(pin 13) V
IANTD mA
VCL input V
VCL V
OSC buffer output, VOSC BUFF dBµ
OSC buffer output, VOSC BUFF dBµ
Unit (capacitance : F)
Capacitive load, CL pF
Load resistance, RL
OSC buffer output, VOSC BUFF dBµ
Supply voltage, VCC V 3SK181+LA1175+LA1140 Overall Characteristics
fOSC kHz
Supply voltage, VCC V AGC Circuit Friquency Characteristic
VAGC V VSM V Pin 10 input dBµ
Unit (resistance : , capacitance : F)
Output dB
ANT input dBµ
Frequency MHz
No.2276-6/14
LA1175, 1175M
Intermodulation Characteristic Desired S/N=80dBµ ANT input dBµ
Intermodulation dummy used
Unit (resistance : ) Undesired ANT input 1, 2 dBµ Cross Modulation Characteristic
Intermodulation Characteristic Desired S/N=30dB antenna input dBµ
Desired S/N=30dB antenna input dBµ
Undesired antenna input dBµ
Undesired antenna input dBµ
Improvement of IM characteristic in strong undesired input signal mode when ANT damping AGC is used (LA1174). Test conditions fD : 99.1MHz, fm=400Hz 100% mod Desired signal fU1 : 97.9MHz non-mod SG open 132dBµ fU2 : 96.7MHz fm=1kHz 100% mod
Undesired signal 1 ANT circuit Undesired signal 2
Intermodulation dummy Unit (resistance : )
No.2276-7/14
LA1175, 1175M Cross point
The open input level of undesired signal 2 at which the IM output and desired signal output are at the same level. IM output · Desired signal : Non-mod at each specified input · Undesired signal 1 : Non-mod at input 132dBµ (SG open) · Undesired signal 2 : 100% mod with input variable Desired signal output · Desired signal : 100% at each specified input · Undesired signal 1 : Non-mod at input 132dBµ (SG open) · Undesired signal 2 : Non-mod with input variable Desired input level With ANT damping RF AGC and ANTD AGC Without ANT damping RF AGC only Improvement 50dBµ 90.5dBµ 60dBµ 109dBµ 70dBµ 123dBµ 80dBµ Test impossible 98dBµ Refer to Fig. A.
Cross point
59.5dBµ 31dB
72dBµ 37dB
89dBµ 34dB
Refer to Fig. B.
Fig. A Intermodulation Characteristic (with ANT damping)
Fig. B Intermodulation Characteristic (with ANT damping)
Output dB
Undesired input 2 dBµ Solid line Solid line
Output dB
Undesired input 2 dBµ
Broken line
Broken line
Intermodulation dummy Unit (resistance : , capacitance F)
Intermodulation dummy
No.2276-8/14
LA1175, 1175M
3SK181+LA1175+LA1140 Cross Modulation Characteristic (Sensitivity Suppression Characteristic in strong undesired input signal mode
S/N dB
f kHz
Unit (resistance : , capacitance : F)
Test Circuit
Shield code
Unit (resistance : , capacitance : F) No.2276-9/14
LA1175, 1175M Sample Application Circuit : LA1175M
Temperature Characteristics (1), (2), (3)
Test Circuit
Unit (resistance : , capacitance : F) No.2276-10/14
LA1175, 1175M Temperature Characteristics (4) Temperature Characteristics (5)
Temperature Characteristics (6)
Temperature Characteristics (7)
Unit (resistance : , capacitance : F) Temperature Characteristic (1) VAGD on, ANTD on sensitivity dBµ Temperature Characteristic (2)
3dB limit sensitivity dBµ
78dBµ sensitivity dBµ
Ambient temperature, Ta °C
VCL (V16) V
VAGC (V13) V
Ambient temperature, Ta °C
No.2276-11/14
LA1175, 1175M
Temperature Characteristic (3) Temperature Characteristic (4)
IANTD (I6) mA
VCL (V16) V
Ambient temperature, Ta °C Temperature Characteristic (4)
Ambient temperature, Ta °C Temperature Characteristic (5)
MIX 78dBµ sensitivity dBµ
ViAGC (AGC block) dBµ
Ambient temperature, Ta °C Temperature Characteristic (5)
Ambient temperature, Ta °C Temperature Characteristic (6)
VO IF max dBµ
Ambient temperature, Ta °C Temperature Characteristic (6)
IF input dBµ
Ambient temperature, Ta °C Temperature Characteristic (6)
Ambient temperature, Ta °C
IF 3dB sensitivity dBµ
VO IF output dBµ
Ambient temperature, Ta °C
No.2276-12/14
LA1175, 1175M
Temperature Characteristic (7) OSC frequency variation, fOSC kHz OSC frequency variation, fOSC kHz Temperature Characteristic (7)
Ambient temperature, Ta °C Temperature Characteristic (7)
Ambient temperature, Ta °C
VOSC dBµ
Ambient temperature, Ta °C
Description of AGC circuit in the LA1175, 1175M
The LA1175, 1175M are designed so that AGC is operated in the order shown below. ANT damping (PIN diode) MOS FET 2nd gate voltage control (Attenuation)20dB (Attenuation)60dB The following are the reasons why AGC is operated in this order. (1) When a signal of 110dBµ or greater is applied to the varactor in the ANT circuit, intermodulation may occur. In this case, if AGC is operated in the order of MOS FET 2nd gate control AGC ANT damping (PIN diode), the input to the varactor in the ANT circuit is not restricted unless a strong signal with AGC attenuation 60dB or greater is given. Therefore, AGC should be operated in the order shown above. (2) If the two AGC loops (AGC loop (ANT damping) and AGC loop (MOS FET 2nd gate control)) are operated simultaneously, the transient response of AGC loses stability. Therefore, the order shown below is impracticable. MOS FET 2nd gate control ANT damping MOS FET 2nd gate control.
No.2276-13/14
LA1175, 1175M Relation between keyed AGC and two AGC loops
For the LA1170, keyed AGC provides AGC attenuation control (RF MOS FET 2nd gate). For the LA1175, 1175M, however, there are two AGC loops as shown above. Therefore, keyed AGC must be applied to both of the two AGC loops. The LA1175, 1175M contain the ANT damping circuit to improve intermodulation in a strong field, but the prevention of intermodulation in a strong field and the improvement of the sensitivity suppression characteristic by keyed AGC are mutually exclusive as mentioned below. Conditions Desired signal Weak field Undesired signals 1, 2 Strong field (Field strength in which the ANT circuit may cause intermodulation to occur) If keyed AGC is operated to cause AGC-OFF mode to be entered when a desired signal is received, the varactor in the ANT circuit may be distorted and intermodulation may occur, which means that it is meaningless for the LA1175, 1175M to contain the ANT damping circuit because it produces no effect. Therefore, the effect of the keyed AGC circuit in the LA1175, 1175M on the ANT damping circuit is made less than that in the LA1170 so that the abovementioned problem does not arise. However, if the LA1175, 1175M are used under the same conditions as for the LA1170 (no ANT damping, pin 6 open), keyed AGC is operated in the same manner as for the LA1170.
Application circuit used in a very strong field
Since the LA1175, 1175M are designed to be operated from single supply, the dynamic range of the MIX output becomes narrower as compared with the dual-supply type (VCC MIX=12V, other=8V) heretofore in use. IF an adjacent interference channel signal is very strong, the intermodulation characteristic at f=400kHz is deteriorated, because the dynamic range of the MIX output exceeds the limit, which causes a distortion to occur. The following three countermeasures are available. 1. Q of the MIX coil is made higher to provide a higher selectivity. (Must be balanced with the detection band of the wide-band AGC) 2. The LA1175, 1175M are operated from dual supplies (Most ideal). 3. The application circuit shown below is used.
Make the resistor value as small as possible.
(add)
Unit (capacitance : F)
No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace equipment, nuclear power control systems, vehicles, disaster/crime-prevention equipment and the like, the failure of which may directly or indirectly cause injury, death or property lose. Anyone purchasing any products described or contained herein for an above-mentioned use shall: Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors and all their officers and employees, jointly and severally, against any and all claims and litigation and all damages, cost and expenses associated with such use: Not impose any responsibilty for any fault or negligence which may be cited in any such claim or litigation on SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors or any of their officers and employees jointly or severally. Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume production. SANYO believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use or any infringements of intellectual property rights or other rights of third parties. This catalog provides information as of September, 1997. Specifications and information herein are subject to change without notice.
No.2276-14/14