NJM2761
-
1
-
Ver.0.5E
Audio Limiter
GENERAL DESCRI PTION
The NJM2761 is the audio limiter for speaker protection.
The limit level is adjustable by extern al resistor .
It is suitable for PC, potable audio and others.
FEATURES
Wide Operating Voltage +2.7V to +13.0V
Variable Limit Level by external resistor 0.2 to1V
Low Output Nois e -90dBV max.
Bipolar Technology
Package Outline TVSP10, SSO P14
BLOCK DIAGR AM
PACKAGE OUTLINE
NJM2761RB2 NJM2761V
Vcc
INT SENSE
OUTb
OUTa
INb
INa
Vref
SW
NJM2761
-
2
-
PIN CONFIGURATION
TVSP10
SSOP14
1. V+
2. OUTa
3. INa
4. INT
5. VREF
6. NC
7. NC
8. NC
9. NC
10. SENCE
11. SW
12. INb
13. OUTb
14. GND
1. V+
2. OUTa
3. INa
4. INT
5. VREF
6. SENCE
7. SW
8. INb
9. OUTb
10. GND
14
13
12
11
10
1
2
3
4
5
6
7
9
8
10
9
8
7
6
1
2
3
4
5
NJM2761
-
3
-
ABSOLUTE MAXIMUM RATING (Ta=25C)
PARAMETER SYMBOL
RATINGS UNIT
Supply Voltage V+ 14 V
Power Dissipation PD 320(TVSP10)
300(SSOP14) mW
Operating Temperature Range Topr -20 to +75 C
Storage Temperature Range Tstg -40 to +125 C
ELECTRICAL CHARACTERISTICS
POWER SUPPLY (Ta=25C, V+=5V unless otherwise specified)
PARAMETER SYMBOL
TEST CONDITION MIN. TYP. MAX. UNIT
Operating Voltage V+ - 2.7 5.0 13.0 V
Operating Current ICC No Signal - 1.5 2.0 mA
Reference V oltage Vref No Signal 2.2 2 . 5 2.7 V
AC CH AR ACTERI STICS
(Ta=25C, V+=5V, VIN=1Vrms/f=1kHz, Rsense=20k, BW=400-30kHz unless otherwise specified)
PARAMETER SYMBOL
TEST CONDITION MIN.
TYP. MAX. UNIT
Limit Level 1 GLIM1 150 200 250 mVrms
Limit Level 2 GLIM2 V+=13V,Rsense=4k,VIN=2Vrms
0.7 1.0 1.3 Vrms
Limit Off GOFF SW =2V 0.9 1.0 1.1 Vrm s
Output Noise VNO RS=0, A-weighting,
- -100
(10) -90
(31.6) dBV
(Vrms)
Total Harmonic Distortion THD+N - - 1 %
Cross Talk CT - - -70 dB
Ripple Rejection RR Vripple=100mVrms, f=1kHz - - -70
(316) dBV
(Vrms)
CONTROL CHARACTERISTICS (Ta=25C, V+=5V unless otherwise specified)
PARAMETER SYMBOL
TEST CONDITION MIN. TYP. MAX. UNIT
Low Level Input Voltage VIL - - - 0.5 V
High Level Input Voltage VIH - 2.0 - - V
CONTROL TERMINAL EXPLANATION
SW(TVSP10:7pin, SSOP14:11pin)
MODE STATUS
NOTE
Limiter ON L Limiter is active.
Limiter OFF H Limiter is not active.
NJM2761
-
4
-
TERMINAL DESCRIPTIO N
No,
TVSP10(SSOP14)
SYMBOL FUNCTION EQUIVALENT CIRCUIT VOLTAGE
1 V+ Power Supply Terminal
-
2
9(13) OUTa
OUTb Ach Output Ter minal
Bch Output Ter minal
V+/2
3
8(12) INa
INb Ach Input Terminal
Bch Input Terminal
V+/2
4 INT Sm oothing Capacitor
Connection
Terminal
0.7V
5 VREFIN Reference Voltage Stabilizing
Capacitor Connection Terminal
V+/2
OUTa
OUTb
100
INa
INb
48k
96k
1k
INT 400
VREFIN
300k
300k
300k
NJM2761
-
5
-
TERMINAL DESCRIPTIO N
No.
TVSP10(SSOP14)
SYMBOL FUNCTIO N EQUIVALENT CIRCUIT VOLTAGE
6(10) SENSE Resister Connection Terminal
for Limit Level Setting
0V
7(11) SW Limiter ON/OFF Switch
-
10(14) GND Ground Terminal
-
SW
150k
270k
SENSE
12k
NJM2761
-
6
-
14
13
12
11
10
OUTa
INT
INa
GND
VREF
SENSE
SW
INb
OUTb
0.22uF
V
+
0.22uF
1uF
0.22uF
0.22uF
1uF
1
2
3
4
5
V+
R
SE NSE
0.022uF
6
7
9
8
NC
NC
NC
NC
APPLICATION CIRCUIT
TVSP10
SSOP14
* The limit level is twice as much as set point when a signal is input into a either one channel of Ach or
Bch.
* For the above reason, monaural signal should input both INa and INb .
RSENSE=4000/Vlim[Ohm ]
Vlim: Limit level(Vrms)
Limit range: 200mVrms to 1Vrms (20k to 4kOhm)
* Please be carefu l of leakag e current from the surrounding wiring because the INT terminal is high
impedance.
10
9
8
7
6
OUTa
INT
INa
GND
VREF
SENSE
SW
INb
OUTb
0.22μF
V+
0.22μF
1μF
0.22μF
0.22μF
1μF
1
2
3
4
5
V+
R
SENSE
0.022μF
NJM2761
-
7
-
TYPICAL CHARACTERISTICS
0
0.5
1
1.5
2
0 5 10 15
V+ - Icc
Vcc[V]
V+=5V,No-Signal,Limiter=ON,Rsense=20k
Icc[mA]
0
0.5
1
1.5
2
-20 0 20 40 60 80
Icc-Temperature
Icc[mA]
Temperature [Co]
V+=5V,No-Signal,Limiter=ON,Rsense=20k
0.01
0.1
1
0.01 0.1 1
L imit Response-V+
Output[Vrms]
Input[Vrms]
Vin=0dBV,Limiter=ON,Rsense=20k
V+=13.0V
V+=2.7V
V+=5.0V
0.01
0.1
1
10
0.0001 0.001 0.01 0.1 1
Vom
THD[%]
Input[Vrms]
f=1kHz,Limiter=OFF,Rsense=20k
V+=2.7V
V+=5.0V
V+=13.0V
0.01
0.1
1
0.01 0.1 1
Limit Response-Rsense
Output [Vrms]
Input[Vrms]
V+=5V,f=1kHz,Limiter=ON
Rsense=4k
Rsense=8k
Rsense=20k
0.01
0.1
1
0.01 0.1 1
Limit Response-Temperature
Output [Vrms]
Input[Vrms]
-20Co
25Co
75Co
V+=5V,Vin=0dBV,Limiter=ON,Rsense=20k
NJM2761
-
8
-
TYPICAL CHARACTERISTICS
[CAUTION]
The specifications on this databook are only
given for information , without any guarantee
as regards ei ther 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 i ncluding
the industrial ri ghts.
-100
-80
-60
-40
-20
0
100 1000 10000
Ripple Rejection
Ripple[dBV]
Frequency[Hz]
V+=5V,Vripple=100mVrms,Limiter=ON
-20Co25Co
75Co
0.01
0.1
1
10
0.001 0.01 0.1 1
THD-Vcc
THD[%]
Input[Vrms]
f=1kHz,Limiter=ON,Rsense=20k
V+=2.7V
V+=5.0V
V+=13.0V
0.01
0.1
1
10
0.001 0.01 0.1 1
THD-Temperature
THD[%]
Input[Vrms]
V+=5V,Vin=0dBV,Limiter=ON,Rsense=20k
-20Co
25Co
75Co
-100
-95
-90
-85
-80
-75
-70
-65
-60
100 1000 10000
Cross Talk
Cross Talk[dB]
Frequency[Hz]
V+=5V,Vin=0dBV,Limiter=ON,Rsense=20k
-20Co
25Co75Co