Any and all SANYO products described or contained herein do not have specifications that can handle
applications that require extremely high levels of reliability, such as life-support systems, aircraft’s
control systems, or other applications whose failure can be reasonably expected to result in serious
physical and/or material damage. Consult with your SANYO representative nearest you before using
any SANYO products described or contained herein in such applications.
SANYO assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges,or other
parameters) listed in products specifications of any and all SANYO products described or contained
herein.
Monolithic Linear IC
PLL FM MPX Stereo Demodulator with Adjustment-Free VCO
and Measure Against Adjacent Channel Interference
Ordering number:ENN2393
LA3450
SANYO Electric Co.,Ltd. Semiconductor Company
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN
Overview
The LA3450 is a multifunctional, high-performance FM
multiplex demodulator IC designed for high-grade FM stereo tuner use. The LA3450 features adjustment-free VCO,
measure against adjacent channel interference, pilot canceler, low distortion (0.005%), and high S/N (101dB).
Applications
• Home stereo, CD, AV-use PLL FM MPX stereo demodulator IC with adjustment-free VCO.
Package Dimensions
unit:mm
3029A-DIP28S
[LA3450]
28
1
27.2
15
14
10.16
8.6
0.25
Functions
• PLL multiplex stereo demodulator.
• Adjustment-free VCO.
• Measure against adjacent channel interference.
• Pilot canceler.
• Cal-tone signal generator.
• AM/FM input, AM/FM selector.
• Post amplifier (gain variable type).
• VCO stop.
• Right/left independent adjustment of separation (single
adjustment available).
Features
• Adjustmet-free VCO : Eliminates the need to adjust freerunning frequency.
• Good temperature characteristics of VCO : ±0.1% typ.
for ±50°C change.
• No antibirdie filter is required because a measure is taken
against adjacent channel interference.
• Less carrier leak 19kHz : 53dB 38kHz : 50dB
• The on-chip cal-tone signal generator facilitates application of recording calibrator.
• Low distortionMONO 0.005% STEREO 0.015%
• High S/N101dB typ. MONO IHF-A BPF
• High voltage gainFM : 10dB (gain variable)
AM : 16dB (gain variable)
• Wide dynamic range Output level 3.3V typ. (THD=1%,
MONO)
2.031.78
0.48
0.95
4.25
4.95max
3.2
0.51min
SANYO : DIP28S
21500TH (KT)/2187TA No.2393–1/15
Page 2
LA3450
Specifications
Absolute Maximum Ratings at Ta = 25˚C
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egatloVylppuSmumixaMV
tnerruCevirDpmaLI
noitapissiDrewoPelbawollAxamdP086Wm
erutarepmeTgnitarepOrpoT07+ot02–
erutarepmeTegarotSgtsT521+ot04–
Operating Conditions at Ta = 25˚C
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egatloVylppuSdednemmoceRV
egatloVgnitarepOV
egatloVlangiStupnIdednemmoceRV
Electrical Characteristics at Ta = 25˚C, VCC=13V, Input : 400mV, f=1kHz, L+R=90%, pilot=10%
(Note 1) : The capture range is represented by the value in 19kHz equivalent.
(Note 2) : The low-pass filter used to measure electrical characteristics must have 19kHz attenuation of –90dB or more
negative value of dB and 38kHz attenuation of –70dB or more negative value of dB.
(Note 3) : Be carefull that the combination of pin 22 ⊕ and the others causes dielectric breakdown easily.
xam61V
CC
xam03Am
L
˚C
˚C
CC
po51ot01V
CC
i
nimpytxam
zH001=f05Bd
zHk1=f5406Bd
zHk01=f05Bd
ONOMMF500.050.0%
NIAMMF510.080.0%
tupniVm002MA20.080.0%
%1=DHT,ONOMMF0080021Vm
MA004006Vm
ONOMMF07700110051Vm
tupniVm002MA07700110051Vm
91
83
MA →Vm002tupniMA,MF0708Bd
MF →Vm004tupniMF,MA0708Bd
For the separation adjusting method when the input separation is more than 0.92, see Sample Application Circuit (2).
(Note 1) In this Sample Application Circuit, the DC voltage on pins 11, 17 is almost equal to that on pin 27 and no DC cut
capacitor (C8 in Sample Application Circuint (1) , (2) ) is required.
No.2393–6/15
Page 7
LA3450
Description of External Parts
NameSymbolKindValueRemarks
CapacitorC1Ceramic100 to 1000pFInprovement in stereo low-frequency distortion
(Note1)
C2Polyester film0.047µFDC cut
C3Electrolytic0.1 to 0.47µFLoop filter, Input pilot 8mV or greater : 0.1µF
14mV or greater : 0.22µF
20mV or greater : 0.47µF
C4Electrolytic0.47µF to 1µFLoop filter, Input pilot 8mV or greater : 0.47µF
14mV or greater : 1µF
C5Electrolytic1µFSync detection filter
C6Electrolytic1µFSync detection filter
C7Polyester film0.01µFFor integration (generation of triangular wave)
C8Polyester film0.01µFDC cut
C9Electrolytic0.47µFFor integration (generation of triangular wave)
C10Electrolytic0.47µFDC cut
C11 to 12 Ceramic510pFDe-emphasis capacitor, R5. C11=50µs (75µs)
R4. C12=50µs (75µs)
C13Electrolytic10µFDC cut
C14Electrolytic33µFDC cut
C15Electrolytic100µFFilter, S/N improvement
C16Electrolytic100µFPower filter
C17 to 18 Electrolytic10µFDC cut
C19Ceramic1000pFLPF for sub signal attenuation
C20 to 21 Ceramic100pFImprovement in separation at high frequencies (Note 2)
C22Ceramic4700pF19kHz tank circuit (generation of sine wave)
ResistorR1Carbon3.3 to 6.8kΩLoop filter, Input pilot 8mV or greater : 6.8kΩ
14mV or greater : 3.3kΩ
R2Carbon10kΩFixing of cal-tone OSC frequency
R3Carbon1kΩLimiting resistor
R4 to 5Carbon100kΩPost amplifiler feedbak resistor, de-emphasis resistor
R6 to 7Carbon100kΩFor separation adjustment
R8 to 9Carbon3.3kΩLPF input resistor (Note 3)
R10 to 11 Carbon3.3kΩLPF output resistor
R12Carbon2kΩLPF for sub signal attenuation
R13Carbon10kΩGeneration of pilot cancel signal
SemifixedVR1Carbon30kΩPilot cancel adjustment
resistorVR2 to 3Carbon1MΩSeparation adjustment
ResonatorXCeramicCSB456F11 (Murata), KBR-457HS (Kyocera)
DiodeD1Silicon (Low leak)Improvement in stereo start time after VCO stop release
CoilL115mH19kHz tank circuit (generation of sine wave)
Note 1 : C1 differs with set models. Capacitor used to phase the sub signal of the decoder with the reproduction sub signal
in the PLL.
Note 2 : C20 to 21 are set to the optimum value according to each set mode.
Note 3 : The LPF input resistor value is 3.3kΩ or greater.
No.2393–7/15
Page 8
Sample Printed Circuit Pattern
LA3450
Proper Cares in Applications
1. Ceramic resonator
Shown below are ceramic resonators recommended for use in the LA3450 and their suppliers.
CSB456F11MurataPiezoelectric Division
TEL : 0762-40-2381
KBR-457HSKyoceraElectronic Parts Division
TEL : 075-592-3851
2. Loop filter constants
Loop filter constants (C3, C4, R1) connected to pins 3, 4 must be set to the optimum value according to an input pilot
level. The recommended values are shown in Table 1.
Table 1. Input Pilot Level – Loop Filter Constants
Note : For example, when the loop filter constants are C3=0.22µF, C4=1µF, R1=3.3kΩ, stereo operation can be per-
formed with an input pilot level of 14mV or greater, even with the temperature characteristics of the OSC
circuit, the initial tolerance and secular chage of a ceramic resonator considerd.
No.2393–8/15
Page 9
LA3450
3. VCO stop method
VCO OSC can be stopped and the forced monaural mode is entered by applying a voltage of 2.5V or greater to pin 10.
The maximum voltage to be applied to pin 10 is 16V regardless of the voltage on pin 28 (VCC pin). The relation
between applied voltage and flow-in current is shown in Fig. 1.
Fig. 1. Voltage Applied to pins 10, 26 – Flow-in Current
4. Forced monaural mode
Connecting pin 16 to GND through a resistor of 10kΩ causes the forced monaural mode to be entered.
5. AM/FM mode select method
The AM/FM mode can be selected by applying a v oltage to pin 26. When the voltage on pin 26 is 0.5V or less, the FM
mode is entered, and when 2.5V or greater, the AM mode is enterd. In AM mode the VCO stops and the forced
monaural mode is entered. The relation between voltage on pin 26 and flow-in current is as shown in Fig. 1.
6. Separation adjust method
The separation is adjusted by varying the gain of the main signal with VR2, VR3 as shown in the Sample Application
Circuit. Sample Application Circuit (1) or (2) is used according to the attenuation of the input sub signal. When the
attenuation ratio of the sub signal to the main signal is 0.92 or greater to 1, use Sample Application Circuit (1), and
when 0.92 or less to 1, use Sample Application Circuit (2). Capacitors C20 and C21, which are used to improve the
separation characteristic at high frequencies, must be set to the optimum values according to your model set.
7. Cal-tone
The OSC frequency can be set with R2, C9 in the Sample Application Circuit (refer to Fig. 2). The OSC level can be
attenuated on connecting resistor Rx across pin 15 and pin 16 (refer to Fig. 3). When tthe S2 is turned on, the triangular
wave generated on pin 15 is amplified by the post amplifier and output. The level at pins 18, 20 is approximately 4V
(p-p) when the typical constants are used in the Sample Application Circuit and the output level becomes approximately 4X20/ (Rx+20) V (p-p) by connecting Rx.
Fig. 3. OSC Level Variable
No.2393–9/15
Page 10
LA3450
8. VO – IO characteristic at pin 27
Fig. 4 shows VO – IO characteristic at pin 27 (IO : Capable of being drawn to the outside)
Maximum current : 3mA
9. Feedback resistance of post amplifier and total gain, de-emphasis constants
Table 2 shows the feedback resistance of post amplifier and the total gain, de-emphasis constants.
Total gain : At monaural mode, R4 · C12=R5 · C11=50µs, 75µs
Table 2. Feedback resistance of post amplifier and of total gain, de-emphasis constants
10. Low-pass filter
Figs. 5, 6 show a sample circuit configuration and characteristic of the low-pass filter.
Fig. 5 Sample Circuit of LC Filter
No.2393–10/15
Page 11
LA3450
Fig. 6 f Response
Note : As the use of this low-pass filter makes the attenuation less at 19kHz, 38kHz, carrier leak at the LPF output
causes the stereo distortion and separation characteristics to get worse than specified in the Electric Character istics. For example, the stereo distortion becomes approximately 0.5% due to carrier leak.
No.2393–11/15
Page 12
LA3450
No.2393–12/15
Page 13
LA3450
No.2393–13/15
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LA3450
No.2393–14/15
Page 15
LA3450
Specifications of any and all SANYO products described or contained herein stipulate the performance,
characteristics, and functions of the described products in the independent state, and are not guarantees
of the performance, characteristics, and functions of the described products as mounted in the customer's
products or equipment. To verify symptoms and states that cannot be evaluated in an independent device,
the customer should always evaluate and test devices mounted in the customer's products or equipment.
SANYO Electric Co., Ltd. strives to supply high-quality high-reliability products. However, any and all
semiconductor products fail with some probability. It is possible that these probabilistic failures could
give rise to accidents or events that could endanger human lives, that could give rise to smoke or fire,
or that could cause damage to other property. When designing equipment, adopt safety measures so
that these kinds of accidents or events cannot occur. Such measures include but are not limited to protective
circuits and error prevention circuits for safe design, redundant design, and structural design.
In the event that any or all SANYO products(including technical data,services) described or
contained herein are controlled under any of applicable local export control laws and regulations,
such products must not be exported without obtaining the export license from the authorities
concerned in accordance with the above law.
No part of this publication may be reproduced or transmitted in any form or by any means, electronic or
mechanical, including photocopying and recording, or any information storage or retrieval system,
or otherwise, without the prior written permission of SANYO Electric Co. , Ltd.
Any and all information described or contained herein are subject to change without notice due to
product/technology improvement, etc. When designing equipment, refer to the "Delivery Specification"
for the SANYO product that you intend to use.
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 February, 2000. Specifications and information herein are subject
to change without notice.
PS No.2393–15/15
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