SANYO LA1837

Ordering number : EN5688C
Monolithic Linear IC
For Home Stereo IC with Electronic Tuning Support
LA1837
Single-Chip IC
Overview
The LA1837 is a single-chip AM/FM IF and MPX IC that supports electronic tuning and was developed for use in home
stereo systems. It is optimal for use in automatic station selection systems that use the SD and IF counting techniques.
Features
• On-chip MPX VCO (no external components required).
• Adjacent channel interference rejection function (third and fifth order).
• Supports both the SD and the IF counting techniques.
• The AM and FM SD sensitivities can be set independently.
• The AM and FM output levels can be set independently.
• Improved AM practical sensitivity and high-input distortion characteristics.
Functions
• AM :
• FM-IF :
• MPX :
RF amplifier, mixer, oscillator, IF amplifier, detector AGC, oscillator buffer, S-meter, narrowband SD,
IF buffer
IF amplifier, quadrature detector, S-meter, Scurve detector, IF buffer output
PLL stereo decoder, stereo display, forced mono, VCO stop, post amplifier, audio muting, adjacent channel
interference rejection function
Specifications
Maximum Ratings at Ta = 25°C
Parameter
Symbol
Conditions
Ratings
Unit
Maximum supply voltage
VCC max
Allowable power dissipation
Pd max
Operating temperature
Topr
-20 to +70
°C
Storage temperature
Tstg
-40 to +125
°C
Ta ≤ 70°C
12
V
550
mW
Any and all SANYO Semiconductor Co.,Ltd. products described or contained herein are, with regard to
"standard application", intended for the use as general electronics equipment (home appliances, AV equipment,
communication device, office equipment, industrial equipment etc.). The products mentioned herein shall not be
intended for use for any "special application" (medical equipment whose purpose is to sustain life, aerospace
instrument, nuclear control device, burning appliances, transportation machine, traffic signal system, safety
equipment etc.) that shall require extremely high level of reliability and can directly threaten human lives in case
of failure or malfunction of the product or may cause harm to human bodies, nor shall they grant any guarantee
thereof. If you should intend to use our products for applications outside the standard applications of our
customer who is considering such use and/or outside the scope of our intended standard applications, please
consult with us prior to the intended use. If there is no consultation or inquiry before the intended use, our
customer shall be solely responsible for the use.
Specifications of any and all SANYO Semiconductor Co.,Ltd. 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.
70109 SY / 62409 MS PC/82097HA(OT) No.5688-1/9
LA1837
Operating Conditions at Ta = 25°C
Parameter
Symbol
Recommended supply voltage
VCC
Operating supply voltage range
VCC op
Conditions
Ratings
Unit
9
V
7 to 11
V
Electrical Characteristics at Ta = 25°C, VCC = 9V, in the specified test circuit
Parameter
Symbol
Ratings
Conditions
min
typ
Unit
max
FM Mono characteristics fc = 10.7MHz, fm = 1kHz, with the coil adjusted so that VAFC - VREG = 0V
Current drain
ICCO-FM
With no input
Demodulation output
VOFM
Channel balance
C.B-mono
Total harmonic distortion (mono)
18
31
44
100dBμ, 100% mod. The pin 16 output
730
1100
1460
mVrms
100dBμ, 100% mod.
The pin 16 output/pin 17 output
-1.5
0
+1.5
dB
%
THDFM(1)
100dBμ, 100% mod. The pin 16 output
0.3
1.3
THDFM(2)
100dBμ, 100% mod. The pin 16 output
1.0
5
Signal-to-noise ratio
S/NFM
100dBμ, 100% mod. The pin 16 output
AM rejection ratio
AMR
100dBμ, 100% mod. The pin 16 output
45
65
Limiting input voltage
-3dBL.S.
100dBμ, 100% mod. Referenced to the output.
The input such that the output is down –3 dB.
26
32
72
80
mA
%
dB
dB
38
dBμ
dBμ
LED sensitivity
SDOn-FM
51
60
69
LED bandwidth
SDBW
100dBμ
85
120
170
kHz
IF count buffer output
VIFBuff-FM
100dBμ, The pin 13 output
80
120
160
mVrms
S-meter output
VSM-FM(1)
0dBμ, The pin 11 output
0
0.1
0.5
V
5.0
Muting attenuation
VSM-FM(2)
100dBμ, The pin 11 output
3.6
4.3
Mute-Att
100dBμ, 100% mod. The pin 16 output
75
85
V
dB
FM stereo characteristics fc = 10.7MHz, 100dBμ, fm = 1kHz, L + R = 90%, pilot = 10%
Separation (left)
SepL
L mod. The pin 16 output/pin 17 output
30
45
dB
Separation (right)
SepR
R mod. The pin 17 output/pin 16 output
30
45
dB
Stereo on level
STON
The pilot modulation such that V7 is under 0.7V.
1.3
2.7
5
%
1.3
%
Stereo off level
STOFF
The pilot modulation such that V7 is over 4.5V.
1.5
Total harmonic distortion (main)
THD-main
L + R mod. The pin 16 output
0.3
Adjacent channel interference
Brej-3rd
fs = 113kHz, VS = 90%, Pilot = 10%,
40
dB
40
dB
rejection ratio
%
The pin 16 output vs. the L-R mod. 1kHz
demodulated output
Brej-5th
fs = 189kHz, VS = 90%, Pilot = 10%,
The pin 16 output vs. the L-R mod. 1kHz
demodulated output
AM characteristics fc = 1000kHz, fm = 1kHz
Current drain
Detector output
Signal-to-noise ratio
ICCO-AM
With no input
15
25
35
mA
VOAM(1)
23dBμ, 30% mod. The pin 16 output
100
180
360
mVrms
VOAM(2)
80dBμ, 30% mod. The pin 16 output
200
320
500
mVrms
S/NAM(1)
23dBμ, 30% mod. The pin 16 output
18
22
dB
S/NAM(2)
80dBμ, 30% mod. The pin 16 output
49
55
dB
Total harmonic distortion (mono)
THDAM(1)
80dBμ, 30% mod. The pin 16 output
THDAM(2)
80dBμ, 80% mod. The pin 16 output
LED sensitivity
SDOn-AM
Local oscillator buffer output
VOSC-AM
IF counter buffer output
ST-IF output
S-merer output
0.4
1.2
%
1.0
4.0
%
17
27
37
dBμ
With no input. The pin 30 output
110
160
220
mVrms
VIFBuff-AM
80dBμ, no modulation. The pin 13 output
160
220
300
mVrms
VSTIF-AM
80dBμ, no modulation. The pin 7 output
16
34
48
mVrms
VSM-AM
0dBμ, no modulation.
0
0
0.2
V
No.5688-2/9
LA1837
Package Dimensions
Allowable power dissipation, Pd max -- mW
unit : mm (typ)
3196A
27.0
10.16
16
8.6
30
15
0.25
1
3.95 MAX
(3.25)
3.0
0.51 MIN
0.95
(1.04)
Pd max – Ta
600
550
500
400
300
200
100
0
--40
0.48
--20
0
20
40
60
80
Ambient temperature, Ta -- °C
SANYO : DIP30SD(400mil)
1.78
Block Diagram
OSC
FM SD
ADJ
30
+
29
28
AM AGC
FM SD
BAND-W
VT
RF
OSC
BUFF
+
27
26
L.P.F
+
+
+
25
24
23
22
21
ALC
AM
OSC
20
+
19
18
17
16
3 rd 5 th
DECODER
ANTI-BIRDIE
REG
BUFF
AM-STEREO
L/R-INPUT
L
R
L-OUT R-OUT
L.P.F
AM
AM
MIX RF.AMP
P-DET
φ
MUTE
STEREO
SW
AGC
AM IF
SD
COMP
DET
VCO
304kHz
FF
38k
FF π
19k∠ 2
FF
19k∠θ
PILOT
DET
AM
S-METER
FM
AM / FM
S-METER S-CURVE IF-BUFF
STEREO
DRIVE
VCC
+
6
7
8
9
+
10
11
12
13
14
15
FM
+
MUTE
FM IFT
FM IN
(10.7MHz)
5
AM/FM
IF-BUFF
4
FM VSM
AM VSM
(SD-ADJ)
3
ST-LED
2
TU-LED
1
AM NARROW
SD
GND
AM-IF
AM IF
TUNING
DRIVE
FM
DET
ST
+
+
AM
MONO
VCC
Top view
No.5688-3/9
100
LA1837
Test Circuit
0.047μF
AFC
0.047μF
30
0.01μF
29
28
27
26
25
24
23
+
3.3kΩ 10μF
3.3kΩ 10μF
+
0.033μF
910pF
+
22μF
33μF
3.3μF
+
L-OUT R-OUT
L.P.F
10μF
+
10kΩ
0.033μF
18kΩ
39mH
0.047μF
T1
L.P.F
REG
OSC
20pF
5.1kΩ
1000pF
39pF
OSC
BUFF
(1.45MHz)
50Ω
AM-IN
(1MHz)
+
22
21
20
19
18
17
9
10
11
12
FM AM
VSM V
SM
13
14
16
AM
5kΩ
MONO
1μF
+
+
5kΩ
0.47μF
+
STEREO
FM
1μF
VDD
15
3kΩ IF-BUFF
T3
+
SEEK1000pF
100μF
NORMAL 10kΩ
AM-ST
T2
+
1μF
8
ST
0.047μF
5kΩ
68kΩ
+
47μF
0.047μF
300Ω
7
SD
0.047μF
6
4.7kΩ 51Ω
5
68kΩ
0.047μF
4
1000pF
3
)
75Ω
2
450kHz
(
1
FM IN
(10.7MHz) 0.047μF
100Ω
LA1837
VCC
9.0V
Top view
Pin Functions
Pin No.
1
Pin function
FM IF input
Pin voltage (V)
Vreg
Pin description
Equivalent circuit
Input impedance ri = 330Ω
1
3
2
AM mixer output
VCC
Connect the mixer coil between this pin and VCC.
3
FM IF input bypass
Vreg
Also functions as the MPX regulator filter.
4
AM IF input
Vreg
Input impedance ri = 2kΩ
2
See pin 1.
4
5
GND
6
TU-LED
VCC
0V
Active low
7
ST-LED
VCC
Open collector output
AM-IF output
6
7
AM stereo IF output (pin 7)
The current input must not exceed 150μA.
8
VCC
VCC
9
FM detector
VCC
Recommended detector coil : 600BEAS-9715Z
(The Toko Electric Corporation)
9
10
AM narrow band CF
connection
1.3V
Recommended narrow band CF: BFU450 C4N
(Murata Mfg. Co., Ltd.)
If the narrow band SD is not used, bypass this circuit
10
with a 50Ω resistor and a 0.047μF capacitor
connected in series.
Continued on next page.
No.5688-4/9
LA1837
Continued from preceding page.
Pin No.
11
Pin function
FM-S-meter output
Pin voltage (V)
0V
Pin description
Equivalent circuit
RL = 8kΩ
11
12
AM S-meter output
0V (AM)
The AM SD sensitivity is adjusted with the value of
AM SD sensitivity
the external resistor connected between this pin and
adjustment
ground.
12
28
13
14
AM and FM IF buffer
0V
V13 ≤ 0.5 V : Reception state
output,
1.4 V ≤ V13 ≤ 2.2 V : IF buffer output turned on
output control switch
V13 ≥ 3.5 V : IF buffer output and muting are turned
(mute switch)
on
Phase comparator
low-pass filter
VCC-1.4 (FM)
0V (AM)
(FM/AM switching)
13
Connecting this pin to ground through a resistor sets
the IC to AM mode.
Resistor value limits :
14
2.7kΩ (when VCC = 7V)
3.9kΩ (8V) 5.1kΩ (9V)
6.2kΩ (10V) 7.5kΩ (11V)
15
Pilot detector
VCC-1.0
If a current of 50μA or greater flows from this pin, the
low-pass filter
system is forced to mono.
(forced mono)
Connecting this pin to ground stops the VCO.
(VCO stop)
The resistor limit values are the same as for pin 14.
16
Post amplifier input
Vreg
17
and output
Vreg
18
Output impedance ro = 200Ω
Pin 16 : right output, pin 17 : left output
Inverting inputs
19
15
Pin 18 : right input, pin 19 : left input
18
19
16
17
RNF = 33kΩ
20
MOX output
21
3.5V
Output impedance ro = 3.3kΩ
3.5V
Pin 20 : right de-emphasis
Pin 21 : left de-emphasis
22
MPX input
2.9V
20
21
Input impedance ri = 20kΩ
22
23
FM demodulator
2.8V (FM)
Output impedance ro = 3.0kΩ
output
2.8V (AM)
The separation can be modified by inserting a
23
capacitor between this pin and ground.
Set VO sub/VO main to be about 0 dB.
24
AM detector output
0V (FM)
0.5V (AM)
Output impedance ro = 3.3kΩ
The AM frequency characteristics can be modified
by adjusting the time constants of the circuits
24
between this pin and pin 22, and between this pin
and ground.
25
AM AGC
0V (FM)
The built-in load resistor R = 11kΩ.
0.5V (AM)
25
Continued on next page.
No.5688-5/9
LA1837
Continued from preceding page.
Pin No.
26
Pin function
Pin voltage (V)
AFC
Vreg
Pin description
Equivalent circuit
The FM SD bandwidth can be modified with the
external resistor connected between this pin and pin
28.
27
AM RF input
Vreg
26
Use this pin at the same potential as pin 28.
27
28
REG
Vreg
Vreg = 3.6V
29
OSC
Vreg
Use an oscillator coil between this pin and pin 28.
30
28
Oscillator buffer
1.6V (FM)
The FM SD sensitivity can be modified with the
output,
1.3V (AM)
external resistor connected between this pin and
FM SD sensitivity
ground.
adjustment
Output impedance ro = 20Ω
29
30
Coil specifications (bottom view)
•AM oscillator (for the DUT)
•IFT
HW-50425 (Mitsumi Electric Co., Ltd.)
YD-1073-1 (Mitsumi Electric Co., Ltd.)
3
4
3-2
2T
4-6
9T
2-1
86T
Qo ≥ 80
2
1-2
3
S 4
7T
2-3
94T
fo = 450kHz
2
L = 270μH
1
58T
4-6
Qo = 110
6
1 S
YD-1073
Includes an internal
6
SFU450B
180pF capacitor.
SFU450B included.
•FM detector
600BEAS-9715Z (The Toko Electric Corporation)
3-1
3
4
22T
f = 10.7MHz
Qo = 40
Includes an internal
2
S
1
82pF capacitor.
6
No.5688-6/9
LA1837
Overall FM Characteristics
FM THD/VSM Characteristics
5
VCC = 9V
fc = 10.7MHz
fm = 1kHz, 75kHzdev
Out
Total harmonic distortion, THD -- %
S-meter output, VSM -- V
0
--10
Output -- dBm
--20
--30
--40
--50
AM Out
--60
--70
Noise
VCC = 9V
fc = 10.7MHz
fm = 1kHz, 75kHzdev
--80
--90
0
10
20
30
40
3
2
1
THD
0
50
60
70
80
90
100 110 120
0
10
20
30
70
80
90
100 110 120
1.0
SUB
MAIN
AM
1.0
7
5
3
2
O
2.0
3
2
ON
3.0
Distortion vs. Frequency Characteristics
10
7
5
0.1
7
5
M
Total harmonic distortion, THD -- %
Total harmonic distortion, THD -- %
FM THD Band Characteristics
VIN = 100dBμ
fm = 1kHz, 75kHzdev
3
2
0.01
0.01
0
10.60 10.62 10.64 10.66 10.68 10.70 10.72 10.74 10.76 10.78 10.80
2 3
5 7 0.1
2 3
5 7 1.0
2 3
5 7 10
2 3
Frequency fc -- MHz
Frequency, freq -- kHz
Separation vs. Frequency Characteristics
Adjacent Channel Interference Rejection Ratio
0
p-R
Se
45
--20
35
Vobat -- dB
--30
30
25
20
--40
--50
LA1837
--60
15
--70
10
--80
5
0
0.01
IF = 10.7MHz, 100dBμ, 75kHzdev
VS = 90%
PILOT = 10%
Referenced to the L-R
LA1836
demodulated output.
--10
Sep-L
40
Separation, Sep -- dB
60
Input -- dBμ
4.0
50
50
40
Input -- dBμ
5.0
VSM
4
ST
10
2
3
5 7 0.1
2
3
5 7 1.0
2
3
5 7 10
--90
70
2
90
110
Frequency, freq -- kHz
6
Capture Range Characteristics
90
CR+
4
130
150
170
190
210
230
Frequency, fs -- kHz
SD Sensitivity Adjustment Characteristics
12
80
30
2
SD on -- dBμ
Capture range -- %
70
0
AM FM
60
FM
50
40
30
--2
--4
AM
20
CR -
10
--6
10
20
30
Pilot -- mV
40
0
0
2
4
6
8
10
12
14
16
Rsdadj -- kΩ
No.5688-7/9
LA1837
700
SD Sensitivity Adjustment Characteristics
26
Overall AM Characteristics
0
28
Out
--10
600
--20
Output -- dBm
SD BW -- kHz
500
400
300
--30
--40
--50
200
--60
100
--70
0
6
8
10
12
14
16
18
--80
--20
20
0
0
120
140
R
24
THD = 80%mod
1.0
--15
C
=
.01 0.02
7μ
2μ
μ
F
F
F
1.5
--10
--20
--25
=0
2.0
C
C
Output voltage, VO -- dBV
V
SM
2.5
--30
--35
0.5
THD = 30%mod
0
20
40
60
80
100
120
--40
0.01
140
2
3
5 7 0.1
AM Detector Output Frequency Characteristics (2)
0
22
--5
0.01μF
Ω
0k
R
Ω
R = 18kΩ
3k
R=3
--20
--25
--30
--35
3
5 7 0.1
2
3
5 7 1.0
5 7 1.0
2
3
5 7 10
2
1.0
Total harmonic distortion, THD -- %
24
=1
3
Distortion vs. Ambient Temperature Characteristics
R
--10
2
Frequency, fm -- kHz
Input -- dBμ
--15
22
--5
3.0
Output voltage, VO -- dBV
100
AM Detector Output Frequency Characteristics (1)
3.5
2
80
AM THD / VSM Characteristics
4.0
--40
0.01
60
40
Input -- dBμ
VCC = 9V, fc = 1MHz
fm =1kHz, 30%mod
S/N (80dBμ) = 58dB
0
--20
20
Radj -- kΩ
.04
Total harmonic distortion, THD -- %
S-meter output, VSM -- V
4.5
4
=0
5.0
2
Noise
C
0
VCC = 9V
fc = 1MHz
fm = 1kHz, 30%mod
S/N (80dBμ) = 58dB
2
3
5 7 10
2
7
5
THD sub
3
THD Mono
2
0.1
--40
THD st
--20
0
20
40
THD Main
60
80
100
Ambient temperature, Ta -- °C
Frequency, fm -- kHz
Separation vs. Ambient Temperature Characteristics
90
S/N Mono
80
S/N Stereo
Separation, Sep -- dB
S/N -- dB
70
60
Sep-R
50
Sep-L
40
30
20
10
0
--40
--20
0
20
40
60
80
100
Ambient temperature, Ta -- °C
No.5688-8/9
LA1837
SANYO Semiconductor Co.,Ltd. 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 Semiconductor Co.,Ltd.
products described or contained herein.
SANYO Semiconductor Co.,Ltd. strives to supply high-quality high-reliability products, however, any and all
semiconductor products fail or malfunction with some probability. It is possible that these probabilistic failures or
malfunction could give rise to accidents or events that could endanger human lives, trouble that could give rise
to smoke or fire, or accidents 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 Semiconductor Co.,Ltd. products described or contained herein are
controlled under any of applicable local export control laws and regulations, such products may require 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 consent of SANYO Semiconductor 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 Semiconductor Co.,Ltd. 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.
Upon using the technical information or products described herein, neither warranty nor license shall be granted
with regard to intellectual property rights or any other rights of SANYO Semiconductor Co.,Ltd. or any third
party. SANYO Semiconductor Co.,Ltd. shall not be liable for any claim or suits with regard to a third party's
intellctual property rights which has resulted from the use of the technical information and products mentioned
above.
This catalog provides information as of July, 2009. Specifications and information herein are subject
to change without notice.
PS No.5688-9/9