NJRC NJM2760V Band pass filter for spectrum analyzer display Datasheet

NJM2760
Band Pass Filter for Spectrum Analyzer Display
■ GENERAL DESCRIPTION
The NJM2760 is a band pass filter for spectrum analyzer display.
It includes 4-band BPF amplifier, 4-band detector and recording
level indicator output.
It is suitable for mini-components, CD radio cassette and other
audio components.
■ PACKAGE OUTLINE
NJM2760V
■ FEATURES
● Operating Voltage
+2.7V to +9V
● 4 Band Pass Filters & Detector
● Recording Level Indicator Output
● Low Offset Voltage
5mV typ.
● Adjustable Input Sensitivity
● Bipolar Technology
● Package Outline
SSOP20
■ PIN CONFIGURATION
1
20
2
19
3
18
4
17
5
16
6
15
7
14
8
13
9
12
10
11
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
IN1
IN2
BUF1OUT
BPF2IN1
BPF2IN2
BPF3IN1
BPF3IN2
BPF4IN1
BPF4IN2
GND
20. BUF2OUT
19. BPF1IN2
18. BPF1IN1
17. RECOUT
16. BPF1OUT
15. BPF2OUT
14. BPF3OUT
13. BPF4OUT
12. N.C.
11. V+
■ BLOCK DIAGRAM
5.6kΩ
10kΩ
22nF
V+
6.8kΩ
47nF
BPF
4.7nF
BPF4 out
DET
1µF
1µF
BPF
BPF3 out
DET
1µF
200kΩ
L in
R in
200kΩ
BPF
BPF2 out
DET
1µF
1µF
BPF
BPF1 out
DET
1µF
200kΩ
200kΩ
REC out
DET
1µF
1µF
GND
470pF
–1–
NJM2760
■ ABSOLUTE MAXIMUM RATING (Ta=25°C)
PARAMETER
SYMBOL
+
RATINGS
UNIT
14
V
Supply Voltage
V
Power Dissipation
PD
300
mW
Operating Temperature Range
Topr
-20 to +75
°C
Storage Temperature Range
Tstg
-40 to +125
°C
■ ELECTRICAL CHARACTERISTICS (Ta=25°C, V+=3.3V, VIN=1VPEAK unless otherwise specified)
PARAMETER
SYMBOL
TEST CONDITION
MIN.
TYP.
MAX.
UNIT
-
2.7
3.3
9.0
V
-
1.4
3.0
mA
0.7
1.0
1.42
V
2.1
3.0
-
V
◆Power Supply
+
Operating Voltage
V
Operating Current
Icc
No Signal
◆ AC CHARACTERISTICS
Typical Output Voltage
VOT
Maximum Output Voltage
VOM
Vin=1Vpeak,
f=Center Frequency of BPF
Vin=3Vpeak,
f=Center Frequency of BPF
BPF1 Center Frequency Level
GVBPF1
f=8kHz
-3
0
+3
dB
BPF2 Center Frequency Level
GVBPF2
f=1.2kHz
-3
0
+3
dB
BPF3 Center Frequency Level
GVBPF3
f=300Hz
-3
0
+3
dB
BPF4 Center Frequency Level
GVBPF4
f=80Hz
-3
0
+3
dB
No Signal
-
5
30
mV
DC Offset Voltage
VOS
◆ TEST CIRCUIT
C1 1µF
R2 100kΩ
C2 1µF
IN1
IN2
1
IN1
2
IN2
3
BUF1OUT
4
BPF2IN1
5
BPF2IN2
6
BPF3IN1
7
BPF3IN2
8
BPF4IN1
9
BPF4IN2
10
GND
C3 4.7nF
R3 6.8kΩ
C4 4.7nF
C5 22nF
R4 5.6kΩ
C6 22nF
C7 47nF
R5 10kΩ
C8 47nF
NJM2760
R1 100kΩ
BUF2OUT
20
BPF1IN2
19
BPF1IN1
18
RECOUT
17
C14 1µF
RECOUT
BPF1OUT
16
C13 1µF
BPF1OUT
BPF2OUT
15
C12 1µF
BPF2OUT
BPF3OUT
14
C11 1µF
BPF3OUT
BPF4OUT
13
C10 1µF
BPF4OUT
NC
12
V+
11
C16 470pF
C15 470pF
+
–2–
C9
1µF
V+
NJM2760
■ TERMINAL DESCRIPTION
No.
SYMBOL
FUNCTION
1
2
5
7
9
19
IN1
IN2
BPF2IN2
BPF3IN2
BPF4IN2
BPF1IN2
Input for BPF1-4
Input for recording level detector
Capacitor terminal for BPF2
Capacitor terminal for BPF3
Capacitor terminal for BPF4
Capacitor terminal for BPF1
3
20
BUF1OUT
BUF2OUT
Buffer output
Buffer output
4
6
8
18
BPF2IN1
BPF3IN1
BPF4IN1
BPF1IN1
Capacitor terminal for BPF2
Capacitor terminal for BPF3
Capacitor terminal for BPF4
Capacitor terminal for BPF1
13
14
15
16
17
BPF4OUT
BPF3OUT
BPF2OUT
BPF1OUT
RECOUT
BPF4 output
BPF3 output
BPF2 output
BPF1 output
Recording level detector output
EQUIVALENT CIRCUIT
1.4V
680Ω
FB
VOLTAGE
680Ω
1.4V
1.4V
680Ω
0V
90kΩ
FB
30kΩ
10
GND
Ground terminal
-
11
V+
Power supply terminal
-
–3–
NJM2760
■ APPLICATION CIRCUIT
LIN
RIN
R11 200kΩ
R12 200kΩ
R21 200kΩ
1
IN1
2
IN2
C2 1µF
3
BUF1OUT
4
BPF2IN1
5
BPF2IN2
6
BPF3IN1
7
BPF3IN2
8
BPF4IN1
9
BPF4IN2
10
GND
C3 4.7nF
R3 6.8kΩ
C4 4.7nF
C5 22nF
R4 5.6kΩ
C6 22nF
C7 47nF
R5 10kΩ
C8 47nF
NJM2760
R22 200kΩ
C1 1µF
BUF2OUT
20
BPF1IN2
19
C16 470pF
C15 470pF
BPF1IN1
18
RECOUT
17
C14 1µF
RECOUT
BPF1OUT
16
C13 1µF
BPF1OUT
BPF2OUT
15
C12 1µF
BPF2OUT
BPF3OUT
14
C11 1µF
BPF3OUT
BPF4OUT
13
C10 1µF
BPF4OUT
NC
12
V+
11
+
–4–
C9
1µF
V+
NJM2760
■ APPLICATION NOTE
1. Center Frequency Setting for Band Pass Filters
Band pass filters equivalent circuits as follows.
External Circuit
Internal Circuit
External Circuit
Internal Circuit
C
C
Rb
Rb
to Detector
C
Ra
Ra
to Detector
C
from Input Buffer
Fig.1-a. BPF1's Equivalent Circuit
from Input Buffer
Fig.1-b. BPF2-4 's Equivalent Circuit
Center Frequency (fo) can be formulated as follows.
Table 1. Center frequency setting example
f0 =
2Q
2πCR b
[Hz],
Q=2
BPF1 (8kHz)
BPF2 (1.2kHz)
BPF3 (300Hz)
BPF4 (80Hz)
Ra
)
10 kΩ*
6.8 kΩ
5.6 kΩ
10 kΩ
Rb
)
169 kΩ*
)
113 kΩ*
)
96.5 kΩ*
)
169 kΩ*
C
470pF
4.7nF
22nF
47nF
*) As regards the BPF1, the values of Ra and Rb are fixed. Also as regards the BPF2-4, the values of Rb is fixed.
2. Output Gain Setting for RECout.
Output Voltage of RECout is adjustable by external resistor: R2
Voltage Gain (Gv) is defined as follows.
R [kΩ]
Vout[ Vdc ]
= Gv = 2
100[kΩ]
Vin[ Vpeak ]
–5–
NJM2760
■ TYPICAL CHARACTERISTICS
Supply Current vs. Temperature
V+=3.3V
3
3
2.5
2.5
2
2
25,75°C
Icc[mA]
Icc[mA]
Supply Current vs. Supply Voltage
Ta=-40, 25, 75°C
1.5
1
1.5
1
Ta=-20°C
0.5
0.5
0
0
0
1
2
3
4
5
6
7
8
9
10
-50 -30 -10
10
Vcc[V]
8
RECout
R2=80kΩ
7
Vos [mV]
Vout[VDC]
110 130 150
9
RECout
R2=100kΩ
2.5
2
1.5
RECout
R2=120kΩ
1
6
5
RECout
BPF1out
BPF2out
4
3
2
0.5
BPF3out
BPF4out
1
0
0
0
0.5
1
1.5
2
2.5
3
Output vs. Frequency
V+=3.3V, Vin=1VPEAK
5
75°C
BPF4 BPF3
BPF2
BPF1
25°C
-20°C
-10
-15
-20
-25
-30
10
100
1000
f[Hz]
-50
0
50
Ta[°C]
Vin[VPEAK]
Vout[dB]
90
10
3
–6–
70
DC Offset Voltage vs. Temperature
V+=3.3V
3.5
-5
50
Ta[°C]
INPUT vs. OUTPUT
Vcc=3.3V, Ta=25°C, f=8kHz, R2=R21/ /R22
0
30
10000
100000
100
150
NJM2760
■ TYPICAL CHARACTERISTICS
Input vs. Output Level
V+=3.3V, Vout=BPFout1, fo=8kHz
Input vs. Output Level
V+=3.3V, Vout=BPFout2, fo=1.2kHz
4
4
3
3
75°C
75°C
25°C
Vout[VDC]
Vout[VDC]
25°C
-20°C
2
1
2
-20°C
1
0
0
0
0.5
1
1.5
2
2.5
3
0
0.5
1
Vin[VPEAK]
1.5
2
3
Vin[VPEAK]
Input vs. Output Level
V+=3.3V, Vout=BPF3out, fo=300Hz
Input vs. Output Level
V+=3.3V, Vout=BPF4out, fo=80Hz
4
4
75°C
75°C
3
3
25℃
25°C
Vout[VDC]
Vout[VDC]
2.5
2
-20°
1
2
-20°C
1
0
0
0
0.5
1
1.5
2
2.5
3
Vin[VPEAK]
0
0.5
1
1.5
Vin[VPEAK]
2
2.5
3
Input vs. Output Level
V+=3.3V, Vout=RECout, fo=8kHz
4
75°C
3
Vout[VDC]
25°C
2
-20°C
1
0
0
0.5
1
1.5
2
2.5
3
[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.
Vin[VPEAK]
–7–
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