Page 1
LOW VOLTAGE/POWER NARROW BAND FM IF S1T3361D
INTRODUCTION
The S1T3361D is designed for use in FM dual conversion
communication. It contains a complete narrow band FM demodulation
system operable to less than 2.5V supply voltage. This low-power
narrow-band FM IF system provides the second converter, second IF,
demodulator. Filter Amp and squelch circuitry for communications and
scanning receivers.
FEATURES
• Low power consumption (4.0mA typ. at VCC = 4.0V)
• Excellent input sensitivity
(-3dB limiting, 2.0µV
• Minimum number of external components required.
• Operating Voltage: 2.5 to 7.0V
rms
typ.)
APPLICATIONS
• Cordless phone (for home usage)
16−DIP−300A
16−SOP−225A
• FM dual conversion communications equipment
ORDERING INFORMATION
Device Package Operating Temperature
S1T3361D01-D0B0 16−DIP−300A
S1T3361D01-S0B0 16−SOP−225A
− 20°C to +70°C
1
Page 2
S1T3361D LOW VOLTAGE/POWER NARROW BAND FM IF
PIN CONFIGURATION
OUTPUT
LIMITER
DECOUPLING
DECOUPLING
QUADRATURE
ABSOLUTE MAXIMUM RATINGS
Characteristic Symbol Value Unit
OSC
OSC
MIXER
V
INPUT
INPUT
1
2
3
4
CC
16
15
14
13
RF
INPUT
GND
MUTE
SCAN
CONTROL
S1T3361D
SQUELCH
5
6
7
8
12
11
10
9
INPUT
FILTER
OUTPUT
FILTER
INPUT
AUDIO
OUTPUT
Max. Supply Voltage V
CC (MAX)
Supply Voltage Range V
Detector Input Voltage V
RF Input Voltage (V
≥ 4.0V) V
CC
Mute Function V
Operating Temperature T
Storage Temperature T
CC
I (DET)
I (RF)
MUTE
OPR
STG
10 V
2.5 to 7.0 V
1.0 V
1.0 V
− 0.5 to + 0.5 V
P-P
rms
peak
− 20 to + 70 °C
− 65 to + 150 °C
NOTE:
Absolute maximum ratings are those values beyond which permanent damage to the device may occur. These are stress
ratings only and functional operation of the device at or beyond them is not implied. Long exposure to these conditions may
affect device reliability.
2
Page 3
LOW VOLTAGE/POWER NARROW BAND FM IF S1T3361D
ELECTRICAL CHARACTERISTICS
(VCC = 4.0V, fo = 10.7MHz, ∆f = ± 3kHz, f
Characteristic Symbol Test Conditions Min. Typ. Max. Unit
Operating Current I
Input Limiting Voltage V
Detector Output Voltage V
Detector Output Impedance Z
Recoverd audio output voltage V
Filter Gain G
Filter Output DC Voltage V
Trigger Hysteresis of Filter V
Mute Switch-on Resistance R
Mute Switch-off Resistance R
Scan Control Low Output V
Scan Control High Output V
Mixer Conversion Gain G
Mixer Input Resistance R
Mixer Input Capacitance C
ON (MUTE)
OFF(MUTE)
L (SCAN)
H (SCAN)
V (MIXER)
I (MIXER)
I (MIXER)
= 1kHz, Ta = 25°C, unless otherwise specified)
MOD
CC
Squelch off (V12 = 2V)
Squelch on (V12 = GND)
I (LIM)
O (DET)
O (DET)
O
V
O (DC)
TH
-3.0dB limiting − 2.0 6.0 µV
− − 2.0 − V
− − 400 − W
Vin = 10mV 134 150 168 mV
f = 10kHz, Vin = 5mV 40 48 52 dB
− 1.0 1.5 2.0 V
− − 50 − mV
Mute Low − 10 40 Ω
Mute High 1 - 10 MΩ
Mute off (V12 = 2V) − − 0.5 V
Mute on (V12 = GND) 3.0 − − V
− 30 36 − dB
− − 3.3 − kΩ
− − 2.2 − pF
2.0
3.0
4.0
6.0
8.0
10
mA
mA
dc
rms
dc
dc
dc
3
Page 4
S1T3361D LOW VOLTAGE/POWER NARROW BAND FM IF
CHARACTERISTIC GRAPH
4
Page 5
LOW VOLTAGE/POWER NARROW BAND FM IF S1T3361D
APPLICATION CIRCUIT
Audio
Mixer input
10.7MHz
51Ω
10nF
16 15 14 13 12 11 10 9
Mute
Scan
Control
Squelch
SW input
10kΩ
Filter
Amp out
1.0uF
S1T3361D
470kΩ
Filter
Amp in
1.0uF
510kΩ
Audio
output
AUDIOFINFOUTSQSCANMUTEGNDMIXIN
10nF
8.2kΩ
10.24MHz
Vcc
OSC
OSC
1 2 3 4 5 6 7 8
68pF
220pF
MIXOUT
455MHz
Filter
VCC
LIMIN DECOLPLING QUAD
0.1uF
20kΩ
Quad coil0.1uF0.1uF
In the above application circuit, the audio signal is recovered using a conventional quadrature FM detector.
The absence of an input signal is indicated by the presence of noise above the desired audio frequencies. This
“noise band” is monitored by an active filter and a detector. A squelch trigger circuit indicates the presence of
noise (or a tone) by an output which can be used to control scanning. At the same time, an internal switch is
operated which can be used to mute the audio.
5
Page 6
S1T3361D LOW VOLTAGE/POWER NARROW BAND FM IF
NOTES
6
Loading...