NJM2762 Data Sheet

NJM2762
2-Channel Audio Limiter
 PACKAGE OUTLINE
 GENERAL DESCRIPTION
NJM2762 is a 2-channel audio limiter IC that will
consistently monitor the amplitude of the input audio signals
and prevent them from exceeding a certain limit level.
NJM2762 will sense both input channels separately and
when either input signals exceeded the preset limit level, it will
reduce the gain of both channels together, such that the
output is always balanced and limited to the desired level.
The amount of attenuation will depend on the channel that has
the worst overshoot condtion.
The limit level of NJM2762 can be adjustable by external
resistor - making it is suitable for PC application and any audio
products that required speaker protection at the back-end.
 FEATURES
 Wide Operating Voltage
 Variable Limit Level by external resistor
 Low Output Noise
 Bipolar Technology
 Package Outline
NJM2762RB2
MSOP10 (TVSP10)
NJM2762V
(SSOP14)
2.7V to 13.0V
180mVrms to 1Vrms
-90dBV max.
MSOP10 (TVSP10)*
SSOP14
*MEET JEDEC MO-187-DA / THIN TYPE
 BLOCK DIAGRAM
VREF
VREF
INA
OUTA
Sense Vref
ON/OFF
INB
SW
OUTB
Limiter Level
INT
Ver.0.8E
SENSE
–1–
NJM2762
 PIN CONFIGURATION
MSOP10 (TVSP10)
1
10
5
6
No.
Symbol
1
2
3
4
5
V+
OUTa
INa
INT
VREF
6
SENSE
7
8
9
10
SW
INb
OUTb
GND
Function
Power Supply Terminal
Ach Output Terminal
Ach Input Terminal
Ach Smoothing Capacitor Terminal
Reference Voltage Terminal
Preset Limit Level Terminal
Limiter On/Off Control Terminal
Bch Output Terminal
Bch Input Terminal
Ground
SSOP14
1
14
7
8
No.
Symbol
1
V+
2
OUTa
3
INa
Function
Power Supply Terminal
Ach Output Terminal
Ach Input Terminal
4
INT
5
VREF
Ach Smoothing Capacitor Terminal
6
NC
Not Connected
7
NC
Not Connected
8
NC
Not Connected
Reference Voltage Terminal
9
NC
10
SENSE
11
SW
Limiter On/Off Control Terminal
12
INb
Bch Output Terminal
13
OUTb
Bch Input Terminal
14
GND
Ground
–2–
Not Connected
Preset Limit Level Terminal
NJM2762
 ABSOLUTE MAXIMUM RATING (Ta=25C)
PARAMETER
SYMBOL
+
Supply Voltage
V
Power Dissipation
PD
RATING
UNIT
+14
V
320
300
[MSOP10(TVSP10)]
[SSOP14]
mW
+
Maximum Input Voltage
VIMAX
0 ~ V (Note1)
V
Operating Temperature Range
Topr
-40 ~ +85
C
Storage Temperature Range
Tstg
-40 ~ +125
C
(Note1) Don’t put Input Voltage more than Power Supply Voltage.
 ELECTRICAL CHARACTERISTICS
 POWER SUPPLY (Ta=25C, V+=5V, SW=0 unless otherwise specified)
PARAMETER
SYMBOL
TEST CONDITION
+
MIN.
TYP.
MAX.
UNIT
2.7
5
13.0
V
Operating Voltage
V
Operating Current
ICC
No signal
-
2.5
3
mA
Reference Voltage
Vref
No signal
2.2
2.5
2.8
V
 AC CHARACTERISTICS
+
(Ta=25C, V =5V, VIN=1Vrms, f=1kHz, Rsense=8kΩ, BW=400Hz–30kHz, SW=0 unless otherwise specified)
PARAMETER
SYMBOL
TEST CONDITION
MIN.
TYP.
MAX.
UNIT
130
180
230
mVrms
1.0
1.3
Vrms
Limit Level 1
GLIM1
Limit Level 2
GLIM2
V+=13V, VIN=2Vrms, Rsense=40kΩ,
0.7
Limit Off
GOFF
SW=2V
0.9
1.0
1.1
Vrms
-
-100
(10)
-90
(31.6)
dBV
(µVrms)
THD+N
-
-
1
%
Cross Talk
CT
-
-
-70
dB
Ripple Rejection
RR
-
-
-70
dBV
MIN.
TYP.
MAX.
UNIT
0
-
0.5
V
-
+
V
Output Noise
Total Harmonic Distortion
VNO
RS=0Ω, A-weighting
Vripple=100mVrms
 CONTROL CHARACTERISTICS (Ta=25C, V+=5V, unless otherwise specified)
PARAMETER
Low Level Input Voltage
High Level Input Voltage
SYMBOL
TEST CONDITION
VIL
VIH
2.0
V
 CONTROL TERMINAL EXPLANATION – SW Terminal (TVSP10(MSOP10): Pin7 / SSOP14: Pin11)
MODE
STATUS
TEST CONDITION
Limiter ON
L
Limiter is Active
Limiter OFF
H
Limiter is NOT Active
–3–
NJM2762
 APPLICATION CIRCUIT
MSOP10(TVSP10)
V+
10uF
V+
1uF
2 OUTA
470nF
3 INA
470nF
4 INT
10uF
5
+
GND 10
NJM2762
1
+
1uF
OUTB 9
470nF
INB 8
SW
7
RSENSE
SENSE 6
VREF
SSOP14
V+
10uF
+
1
V+
GND 14
1uF
1uF
2 OUTA
3 INA
470nF
4 INT
10uF
+
RSENSE Setting => See graph on page 9
–4–
NJM2762
470nF
OUTB 13
470nF
INB 12
SW 11
RSENSE
5
VREF
6
NC
NC
7
NC
NC 8
SENSE 10
9
NJM2762
 TERMINAL DESCRIPTION (MSOP10)
Terminal
SYMBOL
FUNCTION
EQUIVALENT CIRCUIT
VOLTAGE
VCC
1
VCC
Supply Voltage
VCC
GND
VCC
2
9
OUTa
OUTb
200Ω
1kΩ
AC Output
VCC/2
GND
VCC
1kΩ
3
8
INa
INb
96kΩ
AC Input
VCC/2
48kΩ
GND
VCC
400Ω
4
INT
Smoothing Capacitor
400Ω
-
16kΩ
GND
–5–
NJM2762
 TERMINAL DESCRIPTION (MSOP10)
Terminal
SYMBOL
FUNCTION
EQUIVALENT CIRCUIT
VOLTAGE
VCC
50kΩ
200kΩ
200Ω
5
VREF
200Ω
Reference Voltage
VCC/2
200kΩ
40kΩ
GND
VCC
200Ω
6
SENSE
Preset Limit Level
28uA x
RSENSE
200Ω
GND
VCC
200Ω
7
SW
150kΩ
Limiter ON/OFF
0V
275kΩ
GND
–6–
NJM2762
 TYPICAL CHARACTERISTICS
Operating current Vs Operating Voltage
Operating current Vs Temperature
No-Signal, Limiter ON, Rsense =8kΩ
No-Signal, Limiter ON, Rsense =8kΩ
3
2.5
85oC
2.5
2.0
25oC
2
1.5
-40oC
13V
5V
Operating Current, Icc (mA)
Operating Current, Icc (mA)
3.0
1.0
0.5
0.0
0
1
2
3
4
5
6
7
8
9
2.7V
1.5
1
0.5
0
-50
10 11 12 13 14
0
100
150
Temperature, ( oC)
Operating Voltage, + (V)
Vref Vs Operating Voltage
Vref Vs Temperature
No-Signal, Limiter ON, Rsense =8kΩ
No-Signal, Limiter ON, Rsense =8kΩ
7.0
7.0
6.0
6.0
5.0
5.0
Vref (V)
Vref, (V)
50
4.0
13V
4.0
-40oC, 25oC, 85oC
3.0
3.0
2.0
2.0
5V
1.0
1.0
2.7V
0.0
0
1
2
3
4
5
6
7
8
9
0.0
-50
10 11 12 13 14
0
50
100
150
o
Operating Voltage, + (V)
Temperature, ( C)
Limit Response - Rsense
Limit Response - V+
V+=5V, Temp=25oC, f=1kHz, Limiter = ON
Temp=25oC, f=1kHz, Limiter = ON, Rsense = 8kΩ
10
10
40kΩ
1
Output [Vrms]
Output [Vrms]
1
20kΩ
8kΩ
0.1
0.01
0.01
5V
13V
0.1
0.1
1
Input [Vrms]
10
0.01
0.01
2.7V
0.1
1
10
Input [Vrms]
–7–
NJM2762
 TYPICAL CHARACTERISTICS
Limit Response - Temperature
Freq Response - V+
V+=5V, f=1Khz, Limiter = ON, Rsense = 8kΩ
Limiter = ON, Vin =0dBV Rsense = 8kΩ, Limit=0.2Vrms
10
0
-2
-4
-6
Output [Vrms]
Output [dBV]
85oC
1
25oC
-40oC
-8
-10
-12
2.7V, 5V
0.1
-14
13V
-16
-18
0.01
0.01
-20
0.1
1
10
10
100
1,000
Input [Vrms]
THD - V+
THD - V+
V+=5V, f=1Khz, Limiter = ON, Rsense = 8kΩ
V+=5V, f=1Khz, Limiter = OFF, Rsense = 8kΩ
10
2.7V
2.7V
5V
1
OutputTHD [%]1
OutputTHD [%]1
100,000
10
1
0.1
13V
0.01
0.001
0.01
0.1
1
10
5V
13V
0.1
0.01
0.01
0.1
Input [Vrms]
1
10
Input [Vrms]
THD - Temperature
THD - Temperature
V+=5V, f=1Khz, Limiter = ON, Rsense = 8kΩ
V+=5V, f=1Khz, Limiter = OFF, Rsense = 8kΩ
10
10
1
OutputTHD [ %]1
1
OutputTHD [%]1
10,000
Freq [Hz]
-40oC
25oC
85oC
0.1
0.1
-40oC
25oC, 85oC
0.01
0.001
0.01
0.1
Input [Vrms]
–8–
1
10
0.01
0.001
0.01
0.1
Input [Vrms]
1
10
NJM2762
TYPICAL CHARACTERISTICS
THD Vs Freq
Vout Vs Rsense
Temp=25oC, Vin=0dBV, Limiter = ON, Rsense = 8kΩ
Temp=25oC, f=1kHz, Limiter = ON,
Vin=1.5Vrms (1Vrms for 2.7V)
100
1.5
1.4
1.3
VCC=5V
1.2
10
1.1
Output [Vrms]
Output THD [%]1
1.0
1
2.7V
VCC=13V
0.9
THD >1% (2.7V)
0.8
0.7
0.6
0.5
13V
0.4
0.1
0.3
THD >10% (2.7V)
0.2
5V
0.1
0.01
VCC=2.7V
0.0
10
100
1,000
Freq [Hz]
10,000
100,000
0
10
20
30
40
50
Rsense [kΩ]
[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.
–9–