NJRC NJM2592

NJM2592
470MHz INPUT MIXER AND 455kHz FM IF DEMODULATOR IC
GENERAL DESCRIPTION
PACKAGE OUTLINE
The NJM2592 is a wide-operating voltage, low-current
FM IF demodulator IC with 455kHz(standard) IF frequency.
It includes an oscillator, mixer, limiting amplifier, quadrature
detector, active filter, and FSK comparator.
The NJM2592 also has a RSSI circuit and RSSI comparator
for carrier sense.
NJM2592V
FEATURES
Wide Operating Voltage
1.8V to 9.0V
Low Operating Current
2.2mA type. at V+ =2.0V, external local oscillator input
Maximum Mixer Input Signal
Frequency
470MHz (reference value)
Level
0dBm
Mixer Input Resistance
50Ω
IF Frequency
455kHz (standard)
Conventional Quadrature Detector
External Phase-shifting Capacitor
External Discriminator or LC Resonant Circuit
RSSI Comparator with Open-Collector Output
Quick Charge/Discharge Circuit for FSK Reference Voltage
Bipolar Technology
Package Outline
SSOP20
BLOCK DIAGRAM
MIX
IN
SENSE RSSI CARRIER FSK CHARGE LPF
SW
OUT
GND LEVEL OUT SENSE OUT
20
19
18
17
16
15
14
12
11
+
-
RSSI COMP FSK COMP
BUFFER
AF
OUT
13
+
+
-
MIXER
LPF
IN
RSSI
FILTER AMP
CHARGE
QUAD
DET
+
-
OSC
IF AMP
Ver.2004-08-25
1
2
3
4
5
6
OSC
(B)
OSC
(E)
MIX
OUT
V+
IF
IN
DEC
7
8
9
IF
FSK
FSK
OUT
VREF1 VREF2
10
QUAD
IN
-1-
NJM2592
ABSOLUTE MAXIMUM RATINGS
PARAMETER
(Ta=25°C)
SYMBOL
RATINGS
UNIT
Supply Voltage
V+
10.0
V
Power Dissipation
Pd
300
mW
Mixer Input Signal Level
VmixMAX
0
dBm
Operating Temperature
Topr
- 40 to +85
°C
Storage Temperature
Tstg
- 40 to +125
°C
RECOMMENDED OPERATING CONDITION
PARAMETER
Supply Voltage
SYMBOL
TEST CONDITIONS
V+
(Ta=25°C)
MIN.
TYP.
MAX.
UNIT
1.8
2.5
9.0
V
ELECTRICAL CHARACTERISTICS
(Ta=25°C, V+=2.0V, fmix=430MHz, flo=429.545MHz, fif=455kHz, fmod=600Hz, fdev=±4kHz, unless otherwise noted)
PARAMETER
SYMBOL
TEST CONDITIONS
MIN.
TYP.
MAX.
UNIT
Current Consumption
Iccq
No signal
1.8
2.2
2.8
mA
Mixer Conversion Gain
Gmix
VinMIX=60dBuVEMF,
Measured at Pin3, without IF
filter, terminated with 2kΩ
16
20
24
dB
IP3
-
95
-
dBuV
Mixer Input Resistance
R in M
-
(50)
-
Ω
Mixer Input Capacitance
Cin M
-
(2.0)
-
pF
Mixer Output Resistance
R oM
-
2.0
-
kΩ
Signal to Noise Ratio 1
S/N1
-
60
-
dB
Signal to Noise Ratio 2
S/N2
-
60
-
dB
Signal to Noise Ratio 3
S/N3
-
30
-
dB
-3dB Limiting Sensitivity
Vin(lim)
IF input
-
22
-
dBuVEMF
IF input, AM=30%
VinIF=60dBuVEMF
-
50
-
dB
-
2.0
-
kΩ
(0.3)
0.45
(0.65)
V
Mixer 3 rd Order Intercept
AM Rejection Ratio
AMR
IF Amplifier Input Resistance
RinIF
RSSI Output Voltage
Vrssi
Mixer input
VinMIX=60dBuVEMF
IF input
VinIF=60dBuVEMF
IF input
VinIF=25dBuVEMF
IF input
VinIF=40dBuVEMF
The values shown in parenthesis are reference values.
-2-
Ver.2004-08-25
NJM2592
PARAMETER
SYMBOL
Demodulated Output Level
V od
Duty Ratio of Wave Shaped Output
DR
Quick Charge/Discharge Current
Ich
High Level Leak Current of
CARRIER SENSE Terminal
Low Level Voltage of
CARRIER SENSE Terminal
Bias Current of
SENSE LEVEL Terminal
High Level Leak Current of
FSK OUT Terminal
Low Level Voltage of
FSK OUT Terminal
TEST CONDITIONS
IF input
VinIF =60dBuVEMF
IF Input
VinIF=60dBuVEMF
FSK REF=GND
LPFOUT=0.4V
MIN.
TYP.
MAX.
UNIT
75
85
95
mVrms
40
50
60
%
35
65
110
uA
IcryH
VCARRIER SENSE=V+
-
(0.0)
-
uA
VcryL
ICARRIER SENSE=100uA
-
0.1
0.4
V
I level
VCARRIER SENSE=0.8V
-
(0.0)
-
uA
IfskH
VFSK OUT=V+
-
(0.0)
-
uA
VfskL
IFSK OUT=100uA
-
0.1
0.4
dB
The values shown in parenthesis are reference values.
Ver.2004-08-25
-3-
NJM2592
TEST CIRCUIT
This test circuit allows the measurement of all parameters described in “ELECTRICAL CHARACTERISTICS”. This
test circuit includes some electrical switches that should be in the suitable position for the measurement of each
parameter.
Circuit diagram
RSSI CARRIER FSK
OUT SENSE OUT
V+
10u
1000p
V+
CHARGE
SWITCH
V+
100k
100k
68k
Lo
Hi
430MHz
20
19
18
17
16
15
14
13
+
11
+
-
RSSI COMP FSK COMP
BUFFER
12
3300p
68k
560p
+
-
MIXER
68k
0.01u
1000p
FILTER AMP
RSSI
CHARGE
QUAD
DET
+
-
OSC
IF AMP
1
2
3
1000p
4
5
6
V+
1000p
10u
0.1u
7
8
9
10
(2)
22p
0.1u
+
V
+
51
10u
CD
3.3k
429.545MHz
IF FILTER
B
A
IF SW
51
455kHz
10u
CD
: Ceramic discriminator, CDBCB455KCAY66 (Murata Manufacturing Co., Ltd, Japan)
IF FILTER : Ceramic filter, CFWB455KEFA004 (Murata Manufacturing Co., Ltd., Japan)
Measurement condition
“Condition1” is the condition for the case of IF input :
IF SW
: in the A position.
IF IN input signal : input frequency(fif) = 455kHz, input level(VinIF)= 60dBuVEMF,
modulation frequency(fmod)=600Hz, deviation fdev=±4kHz
“Condition 2” is the condition for the case of Mixer Input :
IF SW
: in the B position
MIX IN input signal: input frequency(fmix)=430MHz, input level(VinMIX)=60dBuVEMF,
modulation frequency(fmod)=600Hz, deviation fdev=±4kHz
OSC(E)input signal: input frequency(fosc)=429.545MHz, input level(VinOSC)=105dBuVEMF
CERAMIC DISCRIMINATOR (especially designed for NJM2592)
To optimize some important performance, the following ceramic discriminator CD is available. For more information
on this CD and 450kHz CD, please contact the CD supplier.
CDBCB455KCAY71 (Murata Manufacturing Co., Ltd., Japan)
with the external capacitance of 33pF located between pin 9 and pin10.
-4-
Ver.2004-08-25
NJM2592
TERMINAL FUNCTION (Ta=25°C, V+=2.0V)
Pin No.
1
SYMBOL
EQUIVARENT CIRCUIT
V+
OSC (B)
VOLTAGE
FUNCTION
-
Base / Emitter Terminal
Colpitts - type oscillator is formed
with an external oscillator element
of crystal unit or SAW resonator.
Output of an external oscillator
circuit can also input to pin1 or
pin2.
1
20p
2
2
OSC (E)
-
Mixer Output
An external 455kHz ceramic filter is
connected. The typical output
impedance is 2kΩ.
V+
3
MIX OUT
4
V+
3
1.4k
1.1V
-
V+
5
50k
IF IN
1k
1.94V
1k
5
6
6
DEC
1.94V
V+
7
Ver.2004-08-25
FSK VREF1
7
0.55V
Supply Voltage
IF Limiter Amplifier Input
This is an input to the IF amplifier
after passing through 455kHz
ceramic filter. The typical input
impedance is 2kΩ.
IF Decoupling
An external decoupling capacitor
is connected to enhance stability.
FSK Reference Input
This pin is an input of reference
voltage for FSK comparator. An
external capacitor is connected to
create an average DC level of FM
demodulated signal. The choice of
this capacitor is dependent on the
speed of data signal.
A quick charge/discharge circuit
offers the voltage of pin 7 comes
the same voltage of pin 11 quickly.
-5-
NJM2592
Pin No.
SYMBOL
EQUIVARENT CIRCUIT
VOLTAGE
V+
8
FSK VREF2
0.55V
8
40k
IF OUT
FSK Reference Voltage Output
This pin usually keeps open.
This fixed output voltage may be
available for the FSK reference
voltage of wave shaping comparator
by connecting to pin7. This usage
is effective in shaping the data
signal with continuous bits of the
same polarity, and discussed in
another document related to
applications information.
IF Output
An external phase - shifting
capacitor is connected between
pin9 and pin10.
V+
9
FUNCTION
1.19V
9
40uA
10
10
Quadrature Detector Input
An external phase - shifting coil or
ceramic discriminator is connected.
V+
400
400
QUAD IN
1.99V
FM Demodulated Signal Output
An external 3rd order multiple feed
- back filter (RC filter) is connected
between pin11 and pin13.
V+
11
AF OUT
11
1k
0.55V
40uA
-6-
Ver.2004-08-25
NJM2592
Pin No.
SYMBOL
EQUIVARENT CIRCUIT
VOLTAGE
V+
12
LPF IN
0.55V
FUNCTION
Low Pass Filter Input
An external RC components
forms a band pass filter between
pin12 and pin13.
This terminal is biased from pin 11
though an external RC filter.
12
Low Pass Filter Output
13
13
LPF OUT
0.55V
V+
14
CHARGE
SW
14
--
300k
V+
15
15
FSK OUT
--
16
Ver.2004-08-25
CARRIER
SENSE
FSK Output
The FSK comparator is a wave
shaping circuit. A Filter Amplifier
output signal is inverted and wave
shaped. Instead of V+, another
power source can also be used
within the limit of the rated supply
voltage.
Carrier Sense Output
This pin outputs the result of RSSI
comparator by comparing RSSI
output level with an external input
level to pin 18.
V+
16
Quick Charge / Discharge
Control
The power supply output voltage
to pin 14 sets up the quick charge
/ discharge circuit.
Hi : ON
Low : OFF
Instead of V+, another power
source can also be used within
the limit of the rated supply
voltage.
--
-7-
NJM2592
Pin No.
SYMBOL
EQUIVARENT CIRCUIT
VOLTAGE
Received Signal Strength
Indicator Output
Pin 11 outputs DC level
proportional to the log of input
signal level to pin 20.
V+
17
RSSI OUT
FUNCTION
0.05V
17
50k
Sense Level Input
External reference voltage of
RSSI comparator
V+
18
SENSE
LEVEL
19
GND
18
--
Ground
-Mixer Input
The mixer is designed to work up
to 470MHz with the typical input
impedance of RinM = 50Ω and
CinM = 2pF(at 430MHz).
V+
20
MIX IN
0.27V
20
500
Note :
1. ESD protection diodes exist between each of the following pins and V+.
Pin 1,2,3,5,6,7,8,9,10,11,12,13,17,18,20
2. ESD protection diodes also exist between each of the following pins and ground.
Pin 1,2,3,5,6,7,8,9,10,11,12,13,14,15,16,17,18
-8-
Ver.2004-08-25
NJM2592
APPLICATION CIRCUIT
External Local Oscillator Signal Input
RSSI CARRIER FSK
OUT SENSE OUT
V
BPF
+
V
CHARGE
SWITCH
+
Lo
Hi
LNA
20
19
18
17
16
15
14
13
12
11
Input Imp.50ohm
+
-
MIXER
+
+
-
RSSI COMP FSK COMP
BUFFER
FILTER AMP
RSSI
CHARGE
QUAD
DET
+
-
OSC
IF AMP
1
2
3
4
5
6
V+
7
8
9
10
+
CDEC
CREF
DET
TANK
External
Oscillator
V+
IF FILTER
Local Oscillator with External Crystal and LC Resonant Elements
RSSI CARRIER FSK
OUT SENSE OUT
V+
20
19
18
V
17
CHARGE
SWITCH
+
16
Lo
Hi
15
14
13
12
11
Input Imp.50ohm
+
-
MIXER
+
+
-
RSSI COMP FSK COMP
BUFFER
FILTER AMP
RSSI
CHARGE
QUAD
DET
+
-
OSC
IF AMP
V+
1
2
3
4
5
V+
6
7
CDEC
8
9
CREF
DET
Tank
Overtone
Crystal Unit
10
+
V+
IF Filter
Ver.2004-08-25
-9-
NJM2592
EVALUATION PC BOARD
The evaluation board is useful for your design and to have more understanding of the usage and performance of
this device. This circuit is the same as TEST CIRCUIT. Note that this board is not prepared to show the
recommendation of pattern and parts layout.
Circuit Diagram
SENSE RSSI CARRIER FSK CHARGE AF
LEVEL OUT SENSE OUT
SW
OUT
Hi
R6
100k
RF IN
V+
C6
R5
100k
0.01
19
18
17
16
15
14
R3
68k
12
C8
3300p
11
FILTER AMP
RSSI
CHARGE
QUAD
DET
+
IF AMP
OSC
LO IN
R2
68k
+
-
RSSI COMP FSK COMP
BUFFER
1
13
+
+
-
MIXER
R4
68k
C7
560p
C9
1000
C10
1000p
20
Lo
2
C1 NC
1000p
3 C3 4
5
8
+
C12 NC
10u
C2
0.1u
B
IF
FILTER
7
C4
0.1u
V
C13
10u
R8
51
6
+
1000p
A
C2
Position
9
10
C5
33p
+
V
CD
R9
51
IF IN
R1
3.3k
Note:
1. This board is designed for mixer-input type and C2 is factory-configured as follows:
C2
: in the B position
For the case of IF-input type, the position of C2 is necessary to change as follows:
C2
: in the A position
The actual position of C2 is shown in the next page.
2. External components
CF=CFWLB455KEFA004-B0 (Murata manufacturing Co., Ltd.)
CD=CDBCB455KCAY71-B0 (Murata manufacturing Co., Ltd.)
- 10 -
Ver.2004-08-25
NJM2592
Circuit Side View
RF IN
Local IN
R8
C10
Position of C2
for the case of IF-input
C1
C9
C6
R9
C5
IF IN
R7
C4
C7
CF
IC1
NJM2592
CF
RSSI
R2
R4
R10
C2
SENSE
LEVEL
C8
R6
R3
CD
R1
C12
SW
R5
SW
C11
V+
CARRIER
SENSE
AF OUT
FSK OUT
Vcc : Charge ON
GND: Charge OFF
Ground Side View
Note:
1. External Components
C1, C3, C9,C10=1000pF C2,C4=0.1uF C5=33pF
C6=0.01uF C7=560p
C11=0.47uF C12,C13=10uF
R1=3.3kΩ R2,R3,R4=68kΩ R5,R6=100kΩ R7,R10=0Ω R8,R9=51Ω
CF=CFWLB455KEFA004-B0 CD=CDBCB455KCAY71-B0
Ver.2004-08-25
C8=3300pF
- 11 -
NJM2592
TYPICAL CHARACTERISTICS ( Ta=25°C, V+=2.0V, unless otherwise noted )
Mixer Conversion Gain versus Supply Voltage
Current Consumption versus Supply Voltage
No input signal
2.5
Current Consumption Iccq(mA)
Measured at Pin3, terminated with 2kΩ
30
Mixer Conversion Gain Gmix(dB)
3.0
2.0
1.5
1.0
0.5
25
Fmix=400MHz
20
Fmix=100MHz
15
10
5
0
0.0
0
2
4
6
Supply Voltage V+(V)
8
0
10
Demodulated Output versus Supply Voltage
Duty Ratio of Wave Shaped Output (%)
Demodulated Output Level Vod(mVrms)
80
60
40
20
0
55
CHARGE SW=OFF
50
CHARGE SW=ON
45
2
4
6
Supply Voltage V+(V)
8
10
0
2
4
6
Supply Voltage V+(V)
8
10
-3dB Limiting Sensitivity versus Supply Voltage
S/N versus Supply Voltage-Mixer InputCondition 2(Mixer input)
30
Limiting Sensitivity Vin(lim) (dBuVEMF)
Signal to Noise Ratio S/N1(dB)
10
40
0
80
60
40
20
Condition 1(IF input)
25
20
15
10
5
0
0
0
- 12 -
8
Condition 1(IF input)
60
100
100
4
6
Supply Voltage V+(V)
FSK Duty Ratio versus Supply Voltage
Condition 1(IF input)
120
2
2
4
6
Supply Voltage V+(V)
8
10
0
2
4
6
Supply Voltage V+(V)
8
10
Ver.2004-08-25
NJM2592
Mixer Input Level Characteristics
Mixer Conversion Gain versus Frequency
Measured at Pin3, terminated with 2kΩ
30
120
6.0
20
15
10
5
100
5.0
80
4.0
60
3.0
40
2.0
Current Consumption
20
1.0
0
0
10
100
Mixer Input Frequncy fmix(MHz)
0.0
-100
1000
Measured at Pin3, terminated with 2kΩ
800
-40
-20
0
20
Condition 1(IF input)
25
fmix=400MHz
20
fmix=100MHz
15
10
600
400
5
0
200
70
80
90
100
110
Local OSC Input Level (dBuVEMF)
120
440
IF Detuning Characteristics
445
450
455
460
IF Frequency fif(kHz)
465
470
Carrier Sense Characteristics
Condition 1(IF input)
5
2.2
Conditon 1(IF input), SENSE LEVEL=0.8V
2
RSSI Comparator Output Voltage (V)
0
-5
IF Detuning (dB)
-60
AF Output versus Frequency:S-Curve
AF Output Voltage (mV)
Mixer Conversion Gain Gmix(dB)
-80
Mixer Input Level VinMIX(dBm)
Mixer Conversion Gain versus OSC Input
30
Current Consumption Iccq(mA)
25
Mixer Output Level (dBuV)
Mixer Conversion Gain Gmix(dB)
Mixer Output Level
-10
-15
-20
-25
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
-30
0
-15
Ver.2004-08-25
-10
-5
0
5
10
Relative Frequency to fif (kHz)
15
0
0.4
0.8
1.2
1.6
RSSI Output Voltage Vrssi(V)
2
- 13 -
NJM2592
S+N,N,AMR versus Mixer Input
S+N,N,AMR versus IF Input
Condition 2(Mixer input), AM=30%
10
10
Condition 1(IF input), AM=30%
S+N
0
0
-10
-10
-20
-20
S+N,N,AMR(dB)
S+N,N,AMR(dB)
S+N
-30
AMR
-40
-50
-60
-30
-40
AMR
-50
-60
N
N
-70
-70
-80
-80
-20
0
20
40
60
80
100
Mixer Input Level VinMIX(dBuVEMF)
-20
120
RSSI Output versus Mixer Input
20
40
60
80
100
IF Input Level VinIF(dBuVEMF)
120
RSSI Output versus IF Input
Condition 2(Mixer input)
2.4
2.0
V+=9.0V
1.6
V+=2.0V
V+=4.0V
1.2
0.8
RSSI Output Level Vrssi(V)
RSSI Output Voltage Vrssi(V)
2.4
0
Condition 1(IF input)
V+=9.0V
2.0
V+=4.0V
1.6
V+=2.0V
1.2
0.8
0.4
0.4
0.0
0.0
-20
0
20
40
60
80
100
Mixer Input Level VinMIX(dBuVEMF)
120
-20
0
20
40
60
80
100
IF Input Level VinIF(dBuVEMF)
120
Quick Charge/Discharge Current Ich(uA)
Quick Charge/Discharge Current versus
FSK Reference Input Voltage
Condition1 (IF input),LPF OUT=0.45V
80
60
40
20
0
-20
-40
-60
-80
0
200
400
600
800
1000
FSK Reference Input Voltage(mV)
- 14 -
Ver.2004-08-25
NJM2592
Mixer Conversion Gain versus Temperature
Current Consumption versus Temperature
No input signal
2.5
Mixer Conversion Gain Gmix(dB)
Current Consumption Iccq(mA)
2.4
2.3
2.2
2.1
2.0
1.9
1.8
1.7
1.6
25
-20
0
20
40
60
80
fmix=400MHz
20
fmix=100MHz
15
10
1.5
-40
Measured at Pin3, terminated with 2kΩ
30
5
0
100
-40
Ambient Temperature Ta(°C)
Condition 1(IF input)
100
80
100
110
100
55
Duty Ratio DR(%)
Demodulated Output Level Vod(mVrms)
80
Condition 1(IF input)
60
90
80
70
50
45
60
50
40
40
-40
-20
0
20
40
60
80
-40
100
-20
0
20
40
60
Ambient Temperature Ta(°C)
Ambient Temperature Ta(°C)
S/N versus Temperature
-3dB Limiting Sensitivity versus Temperature
70
30
Limiting Sensitivity Vin(lim) (dBuVEMF)
Signal to Noise Ratio S/N1,S/N2(dB)
0
20
40
60
Ambient Temperature Ta(°C)
FSK Duty Ratio versus Temperature
Demodulated Output versus Temperature
120
-20
Condition 1(IF input)
65
Condition 2(MIX input)
60
55
50
25
Condition 1(IF input)
20
15
Condition 2(MIX input)
10
5
0
-40
-20
0
20
40
60
Ambient Temperature Ta(°C)
Ver.2004-08-25
80
100
-40
-20
0
20
40
60
80
100
Ambient Temperature Ta(°C)
- 15 -
NJM2592
RSSI Output versus Temperature-MixerCondition 2(Mixer input)
2.4
2.0
RSSI Output Voltage Vrssi(V)
RSSI Output Voltage Vrssi(V)
2.4
RSSI Output versus Temperature-IF-
70dBuVEMF
60dBuVEMF
1.6
50dBuVEMF
1.2
40dBuVEMF
30dBuVEMF
0.8
20dBuVEMF
0.4
Condition 1(IF input)
2.0
1.6
70dBuVEMF
1.2
60dBuVEMF
50dBuVEMF
0.8
40dBuVEMF
0.4
30dBuVEMF
20dBuVEMF
0.0
0.0
-40
-20
0
20
40
60
80
Ambient Temperature Ta(°C)
100
-40
-20
0
20
40
60
80
Ambient Temperature Ta(°C)
100
Quick Charge/Discharge Current versus Temperature
-20
Condition 1(IF input),LPF OUT=0.45V
Quick Charge/Discharge Current
Ich(uA)
-30
-40
-50
-60
-70
-80
-90
-100
-40
-20
0
20
40
60
80
100
Ambient Temperature Ta(°C)
[CAUTION]
The specifications on this databook are only
given for information , without any guarantee
as regards either mistakes or omissions. The
application circuits in this databook are
described only to show representative usages
of the product and not intended for the
guarantee or permission of any right including
the industrial rights.
- 16 -
Ver.2004-08-25