TA31273FN
2002-07-08
1
TOSHIBA Bipolar Linear Integrated Circuit Silicon Monolithic
T A 3 1 2 7 3 F N
AM RF/IF Detector IC
The TA31273FN is an RF/IF detector IC for AM radio.
The IC incorporates an RF amp, 2-level comparator, and local x8
circuit.
Features
• RF frequency: 240 to 450 MHz
• IF frequency: 10.7 MHz
• Operating voltage range: 3.0 to 5.5 V
• Current dissipation: 6.8 mA (typ.)
(Not operating local oscill ator)
• Current dissipation at BS: 0 µA (typ.)
• Small package: 20-pin SSOP (0.65-mm pitch)
Block Diagram
Weight: 0.09 g (typ.)
102 1 3 4 5 6 7 8 9
1119 20 18 17 16 15 14 13 12
SAW
RSSI
Comparator
×8
FIL
IN
FIL
OUT RSSI BS MIX
IN GND1 RF
DEC
MONI RF
IN
DATA
GND2REF
IF
DEC
IF
IN
VCC2
MIX
OUTLOBS
VCC1
OSC
IN
RF
OUT
TA31273FN
2002-07-08
2
Pin Function (The Values Of Resistor And Capacitor In The Internal Equivalent Circuit
Are Typical.)
Pin
No. Pin Name Function Internal Equivalent Circuit
1 OSC IN Local oscillator input pin.
2 VCC1 Power supply pin 1.
3 LOBS Lo switch pin.
H: x8 circuit in operation
Lo: Through pass
4 MIX OUT Mixer output pin.
5 VCC2 Power supply pin 2.
6 IF IN IF amp input pin.
7 IF DEC IF amp input pin.
Used as a bias coupling pin.
8 REF AM comparator REF pin.
9 GND2 GND pin 2.
10 DATA AM waveform shaping output pin.
Open collector output.
Connect a pull-up resistor.
6 7
170 Ω
170 Ω
3 kΩ
210 Ω
4
2 pF
1
15 kΩ
5 kΩ
5 kΩ
15 kΩ
5 kΩ
60 kΩ
3
2 kΩ
10
8
40 kΩ
40 kΩ
COMP
DATA
20
19
500 Ω
5.5 kΩ
TA31273FN
2002-07-08
3
Pin
No. Pin Name Function Internal Equivalent Circuit
11 RF IN RF signal input pin.
12 RF DEC Emitter pin for internal transistor.
14 RF OUT RF amp output pin.
13 MONI Since this pin is connected to an internal circuit, it
should either be left open or connected to GND.
15 GND1 GND pin 1.
16 MIX IN Mixer input pin.
17 BS Battery saving pin.
18 RSSI RSSI output pin.
19 FIL IN AM LPF input pin.
20 FIL OUT AM LPF output pin.
Equivalent circuits are given to help und erstand design of the exter nal circuits to be connected. They do not
accurately represent the internal circuits.
14
12
11 3 kΩ
50 kΩ
17
16
2.4 kΩ
500 Ω
18
20 kΩ
20 kΩ
13
20 500 Ω
5.5 kΩ
19
TA31273FN
2002-07-08
4
Functions
1. Waveform shaper circuit (comparator)
The output data (pin 10) are inverted.
2. RSSI function
DC potential corresponding to the input level of IF IN (pin 6) is output to RSSI (pin 18). Output to RSSI
(pin 18) is converted to a voltage by the internal resistanc e. Thus, connecting external resistanc e R to pin
18 varies the gradient of the RSSI output as shown below. Note that due to the displacement of
temperature coefficients between external resistor R and the internal IC resistor, the temperature
characteristic of the RSSI output may c hange. Also, the maximum RSSI value should be VCC − 1 V.
Figure 1 Figure 2
3. VCC pin and GND pin
Use the same voltage supply source for VCC1 (pin 2) and VCC2 (pin 5) (or connect them). Also, use the same
voltage supply source for GND1 (pin 15) and GND2 (pin 9) (or connect them).
4. Local oscillator circuit
The local oscillator circuit is external-input-only. Input to pin 1 at a level from 95 to 105dBµV.
By switching the Lo switch (LOBS), the frequency set by the external circuit can be used as-is without
using the x8 circuit.
Lo Switch (LOBS) H L
Local oscillation status x8 circuit in operation x8 circuit halted/through pass
5. RF amp current adjustment
The RF amp current dissipation can be regulated by varying resistor R as shown in the figure below. When
R = 1 kΩ, the current dissipation is approximately 800 µA.
Figure 3
12
R
RF DEC
20 kΩ
18
R
IF input level
A
fter R is connected
TA31273FN
2002-07-08
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6. Battery-saving (BS) function and Lo switch LOBS function
The IC incorporates a battery-saving function and a Lo switch function. These functions offer the following
selection.
BS Pin/LOBS Pin Circuit Status in the IC IC Current Dissipation
(at no signal)
H/H
Circuits in operation
• x8 circuit
• Mixer
• RF amp
• Comparator
• IF amp
• RSSI
• Comparator capacitor charger circuit
6.8 mA (typ.)
H/L x8 circuit only halted, Frequency set by
external circuit can be used as-is. 3.8 mA (typ.)
L/H x8 circuit only in operation 3.0 mA (typ.)
L/L All circuits halted 0 mA (typ.)
7. RF amp gain 1
RF amp gain 1 (GV (RF) 1) is a reference value calculated as follows. Measure GRF in the following figure.
Figure 4
GV (RF) 1 is calculated as follows:
GV (RF) 1 = GRF − GV (MIX)
8. IF amp gain
The intended value is 70dB.
9. Waveform-shaping output duty cycle
The specified range of electrical characteristics is only available for single-tone.
10. Local frequency range (after multiplying frequency by 8)
When the multiplier circuit is used, the local frequency will be in the range 250.7 MHz to 439.3 MHz.
27 nH
1000 pF
1 kΩ
4 6
16 14 11
33 nH
SAW
0.01 µF
SG
50dBµV
GRF
6 pF
6 pF
TA31273FN
2002-07-08
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11. Bit rate filter for AM
The current AM bit rate filter is used as a quadratic filter.
If the filter is to be used at a rate other than 1200 bps, please change the filter constant.
Quadratic filter (NRZ)
(The bit rate filter time constant takes into account the internal resistance RSSI (20 kΩ).)
R9 R8 C14 C13
1200 bps 47 kΩ 68 kΩ 1500 pF 4700 pF
2400 bps 47 kΩ 68 kΩ 680 pF 2200 pF
4800 bps 47 kΩ 68 kΩ 390 pF 1000 pF
When the filter constants shown below are used, it is not necessary to set the R9 constant value.
R9 R8 C14 C13
1200 bps 20 kΩ 2200 pF 6800 pF
2400 bps 20 kΩ 1500 pF 3300 pF
4800 bps 20 kΩ 820 pF 1800 pF
In addition, the current AM bit rate filter can be used as a tertiary filter.
If the filter is to be used at a rate other than 1200 bps, please change the filter constant.
Quadratic filter (NRZ)
(The bit rate filter time constant takes into account the internal resistance RSSI (20 kΩ).)
R10 R9 R8 C16 C14 C13
1200 bps 47 kΩ 68 kΩ 68 kΩ 3300 pF 560 pF 0.01 µF
2400 bps 47 kΩ 68 kΩ 68 kΩ 1500 pF 270 pF 4700 pF
4800 bps 47 kΩ 68 kΩ 68 kΩ 680 pF 150 pF 2200 pF
When the filter constants shown below are used, it is not necessary to set the R10 constant value.
R10 R9 R8 C16 C14 C13
1200 bps 20 kΩ 20 kΩ 8200 pF 2200 pF 0.033 µF
2400 bps 20 kΩ 20 kΩ 3900 pF 1000 pF 0.015 µF
4800 bps 20 kΩ 20 kΩ 1800 pF 470 pF 6800 pF
TA31273FN
2002-07-08
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Maximum Ratings (Unless Otherwise Specfied Ta = 25°C, Voltage Value is Determined by
GND (TYP))
Characteristics Symbol Rating Unit
Supply voltage VCC 6 V
Current dissipation PD 710 mW
Operating temperature range Topr −40~85 °C
Storage temperature range Tstg −55~150 °C
The maximum ratings must not be exceeded at any time. Do not operate the device under conditions outside the above ratings.
Operating available Range
(Unless Otherwise Specified Ta = 25℃, Voltage Value is Determined by GND(typ.))
Characteristics Symbol
Test
Circuit Test Condition Min Typ. Max Unit
Operating voltage range VCC 3.0 5.0 5.5 V
Operating ranges indicate the conditions for which the device is intended to be functional even with the electrical changes.
Electrical Characteristics (Unless Otherwise Specified : Ta = 25°C, VCC = 5.0V , Rfin = 314.9
MHz, AM = 90%,Ifin = 10.7MHz , af = 600 Hz (square wave))
Characteristics Symbol
Test
Circuit Test Condition Min Typ. Max Unit
Current dissipation at no signal Iccq 2
VCC = 5.0 V, BS/LOBS =H/H
Fin (LO) = 40.7 MHz 5.1 6.8 8.5 mA
Current dissipation at battery saving Icco 3 0 5 µA
RF amp gain 1 GV (RF) 1 V
in (RF) = 50dBµV 20 dB
RF amp gain 2 GV (RF) 2 1 (5) 50 Ω input/output −6.5 −3.5 −0.5 dB
RF amp input resistance R (RF) IN 900 Ω
RF amp input capacitance C (RF) IN 2.5 pF
RF amp output capacitance C (RF) OUT 2 pF
Mixer conversion gain GV (MIX) 1 (6) 17.5 21.5 25.5 dB
Mixer input resistance R (MIX) IN 1.5 kΩ
Mixer input capacitance C (MIX) IN 2.5 dB
Mixer output resistance R (MIX) OUT 330
Mixer intercept point IP3 93 dBµV
IF operating frequency fIF 10.7 MHz
IF amp input resistance R (IF) IN 330 Ω
RSSI output voltage 1 VRSSI1 1 (1)
Vin (IF) = 35dBµVEMF 0.1 0.3 0.5 V
RSSI output voltage 2 VRSSI2 1 (1)
Vin (IF) = 65dBµVEMF 0.95 1.20 1.45 V
RSSI output voltage 3 VRSSI3 1 (1)
Vin (IF) = 100dBµVEMF 1.9 2.3 2.7 V
RSSI output resistance RRSSI 15 20 25 kΩ
Waveform shaping output duty cycle DR 1 (2) Vin (IF) = 80dBµVEMF
for single-tone 45 50 55 %
Data output voltage (L level) VDATAL 1 (3) IDATAL = 1 mA 0.4 V
Data output leakage current (H level) IDATAH 1 (4) 2 µA
BS pin H-level input voltage 2.7 5.5 V
BS pin L-level input voltage 0 0.2 V
LOBS pin H-level input voltage 2.7 5.5 V
LOBS pin L-level input voltage 0 0.2 V
TA31273FN
2002-07-08
8
Test Circuit
Test Circuit 1
(1) VRSSI (2) DR
(3) VDATA L (4) IDATA H
SG 6 18
V
62 Ω
0.01 µF
1000 pF
SG 610
62 Ω
0.01 µF
100 kΩ
VCC
V
V
2.5 V
3.0 V
10 VCC
V
R = 4.7 kΩ
8
19
10 VCC
I = V/100 × 103
V
100 kΩ
8
V
V
2.5 V
3.0 V
19
1021 3 4 5 6 7 8 9
111920 18 17 16 15 14 13 12
RSSI
COMP
×8
FIL
IN
FIL
OUT RSSI BS MIX
IN GND1 RF
DEC
MONI RF
IN
DATAGND2REF
IF
DE
C
IF
IN
VCC2
MIX
OUT
LOBS
VCC1
OSC
IN
100 kΩ
0.01 µF
0.01 µF
0.01 µF
0.01 µF
560 pF
68 kΩ
68 kΩ
3300 pF
47 kΩ
1 kΩ
1000 pF
27nH
1 kΩ
VCC
VCC
DATA
R15
C22
C21
C17
C15
VCC
C13
C14 R8
R9
R10 C16
L4
R13
1000 pF
R14
C24
C25
0.22 µF
VCC
RF
OUT
6 pF
1000 pF
C20
0.01 µF
C23
VCC
VCC
0.01 µF
BPF
TA31273FN
2002-07-08
9
(5) Gv (RF) 2 (6) GV (MIX)
Test Circuit 2
I
ccqam
Test Circuit 3
I
cco
SG 11 14
51 Ω
1000 pF
51 Ω
1000 pF
VCC
14 5 2
15 129
A
17
1 kΩ
SG 1
51 Ω
0.01 µF
0.01 µF
SG
51 Ω
16
1000 pF
4
6
145 17 2
15 1
1 kΩ
A
12
51 kΩ
0.01 µF
SG
9
TA31273FN
2002-07-08
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Reference data（This is temperature characteristics data when it used evaluation boards.
This is not guarantee on condition that it is stating except electrical characteristics. ）
Mixer conversion gain Gv (Mix) (dB)
Power supply voltage VCC (V)
Current consumption vs.
Power supply voltage characteristics
Current consumtion Iccq (mA)
Power supply voltage VCC (V)
Current consumption vs.
Power supply voltage characteristics
Current consumtion Iccq (mA)
Power supply voltage VCC (V)
RF amp gain vs.
Power supply voltage characteristics
RF amp gain 2 Gv (RF) 2 (dB)
Power supply voltage VCC (V)
Mixer conversion gain vs.
Power supply voltage characteristics
Power supply voltage VCC (V)
Mixer conversion gain vs.
Power supply voltage characteristics
Mixer conversion gain Gv (Mix) (dB)
10
00 1 2 3 4 5 6
2
4
6
8
25°C 100°C
−40°C
Fin (Lo) = 40.7 MHz
Vin (Lo) = 100 dBµV
BH: H LOBS: H
0
−501
−10
−20
−30
−40
2 3 4 5 6
25°C
100°C
−40°C Fin (RF) = 314.9 MHz
Vin (RF) = 50 dBµV
30
−301 2 3 4 5 6
−20
−10
0
10
20
Fin (MIX) = 314.9 MHz
Vin (MIX) = 50 dBµV
Fin (Lo) = 40.7 MHz
Vin (Lo) = 100 dBµV
LOBS: H
25°C
110°C
−40°C
30
−401 2 3 4 5 6
−30
−20
−10
0
10
20
−40°C
25°C
110°C Fin (MIX) = 314.9 MHz
Vin (MIX) = 50 dBµV
Fin (Lo) = 304.2 MHz
Vin (Lo) = 100 dBµV
LOBS: L
8
00 1 2 3 4 5 6
2
4
6
All internal circuits used
Multiplier circuit t urned off
and external circuit used
Only multiplier
circuit used
BS Fin (Lo) = 40.7 MHz
Vin (Lo) = 100 dBµV
Ta = 25°C
RSSI output voltage VRSSI (V)
MIX IN input level Vin (dBµVEMF)
RSSI output voltage characteristics
(MIX input)
3
0
−20 0 20 40 60 80 120
1
1.5
2
100
2.5
110°C
25°C −40°C
Fin (MIX) = 314.9 MHz
Fin (Lo) = 40.7 MHz
Vin (Lo) = 100 dBµV
0.5
TA31273FN
2002-07-08
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RSSI output voltage VRSSI (V)
Local input level VLO (dBµV)
Mixer conversion gain vs.
Local input level characteristics
Mixer conversion gain Gv (Mix) (dB)
IF IN input Vin (IF) (dBµVEMF)
S/N characteristics (IF input)
S + N, N (dB)
Power supply voltage VCC (V)
FSK duty cycle vs.
Power supply voltage characteristics
FSK duty cycle DR (%)
IF IN input level Vin (dBµVEMF)
RSSI output voltage characteristics
(IF input)
Input frequency Fin (MIX) (MHz)
Mixer conversion gain frequency
characteristics
Mixer conversion gain Gv (MIX) (dB)
25
0
100
5
10
15
20
1000
VCC = 5 V
Vin (MIX) = 50 dBµV
Vin (Lo) = 100 dBµV
LOBS = “L”
* Terminate the IF input
impedance.
110°C
25°C
−40°C
Fin (MIX) = 314.9 MHz
Vin (MIX) = 50 dBµV
Fin (Lo) = 40.7 MHz
25
−15
60 70 80 90 100 110 120
−5
5
15
−10
0
10
20
110°C
25°C
−40°C
10
−9
−10 10 30 50 70 90 130
−7
−3
−5
0
110
−40°C 25°C 110°C
−40°C 110°C
25°C
Fin (IF) = 10.7 MHz
AM = 90%
Fmod = 600 Hz
60.0
40.0
1.00 2.00 3.00 4.00 5.00 6.00
50.0
45.0
55.0
−40°C
25°C
110°C Fin (IF) = 10.7 MHz
Vin (IF) = 50 dBµVEMF
AM = 90%
Fmod = 600 Hz
3.0
40.00 20 40 60 80 120
1.0
2.5
2.0
1.5
0.5
100
−40°C
25°C
110°C
Fin (IF) = 10.7 MHz
TA31273FN
2002-07-08
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Application Circuit
X1 ：TR-1（Tokyo Denpa Co., Ltd.）
BPF：SFE10.7MA5-A（Murata Manufacturing Co., Ltd.）
SAW：SAFCH315MSM0T00B0S（Murata Manufacturing Co., Ltd.）
10 2 1 3456789
11 19 20 18 17 16 15 14 13 12
SAW
RSSI
Comparator
×8
FIL
IN
FIL
OUT RSSI BS MIX
IN GND1 RF
DEC
MONI RF
IN
DATA GND2 REF
IF
DEC
IF
IN
VCC2
MIX
OUT
LOBS
VCC1
OSC
IN
100 kΩ
0.01 µF
0.01 µF
40.7 MHz
0.01 µF
1 pF
120 kΩ
3.3 kΩ
0.01 µF
33 kΩ
0.01 µF
560 pF
68 kΩ
68 kΩ
3300 pF
47 kΩ
1 kΩ
33 nH
1000 pF
27nH
1 kΩ
VCC BPF
VCC
DATA
R15
C22
C21
C17
C15
VCC
10 µF
56 pF
C7
C9
R2
47 pF
C3 R3 C2
C8
C13
C14 R8
R9
R10 C16
L4
R13
1000 pF
R14
C24
C25
6 pF
RF IN
0.22 µF
VCC
RF
OUT
6 pF
1000 pF
C20
0.01 µF
C23
R4
VCC
VCC
X1
TA31273FN
2002-07-08
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Package Dimensions
Weight: 0.09 g (typ.)
TA31273FN
2002-07-08
14
• TOSHIBA is continually working to improve the qu ality and relia bility of its products. Nevertheless, semiconductor
devices in general can malfunction or fail due to their inherent electrical sensitivity and vulnerability to physical
stress. It is the responsibility of the buyer, when utilizing TOSHIBA products, to comply with the standards of
safety in making a safe design for the entire system, and to avoid situations in which a malfunction or failure of
such TOSHIBA products could cause loss of human life, bodily injury or damage to pro perty.
In developing your desig ns, please ensure that TOSHIBA products ar e used within specified operating ra nges as
set forth in the most recent TOSHIBA products specifications. Also, please keep in mind the precautions and
conditions set forth in the “Handling Guide for Semiconductor Devices,” or “TOSHIBA Semiconductor Reliability
Handbook” etc..
• The TOSHIBA products listed in this document are intended for usage in general electronics applications
(computer, personal equipm ent, office equipment, measuri ng equipment, industrial r obotics, domestic applianc es,
etc.). These TOSHIBA products are neither intended nor warranted for usage in equipment that requires
extraordinarily high quality and/or reliability or a malfunction or failure of which may cause loss of human life or
bodily injury (“Unintended Usage”). Unintended Usage include atomic energy control instruments, airplane or
spaceship instruments, transportation instruments, traffic signal instruments, combustion control instruments,
medical instruments, all types of safety devices, etc.. Unintended Usage of TOSHIBA products listed in this
document shall be made at the customer’s own risk.
• The products described in this document are subject to the foreig n exchange and foreign trade laws.
• The information contained herein is presented only as a guide for the applications of our products. No
responsibility is assumed by TOSHIBA CORPORATION for any infringements of intellectual property or other
rights of the third parties which may result from its use. No license is granted by implication or otherwise under
any intellectual property or other rights of TOSHIBA CORPORATION or others.
• The information contained herein is subject to change without notice.
000707EB
A
RESTRICTIONS ON P RODUCT USE
