NJM2831
LOW DROPOUT VOLTAGE REGULATOR
GENERAL DESCRIPTION
The NJM2831 is a 100mA output low dropout voltage regulator
with ON/OFF control.
Advanced Bipolar technology achieves low noise, high ripple
rejection and low quiescent current.
2.1V to 15.5V output voltage range, 1µF small decoupling
capacitor, built-in noise bypass capacitor make the NJM2831
suitable for various applications.
FEATURES
Output voltage options available
2.1
∼
15.5V (0.1V step)
High Ripple Rejection
75dB typ. (f=1kHz Vo=3V Version)
Output Noise Voltage
Vno=45µVrms typ.
Output capacitor with 1.0µF ceramic capacitor (Vo≥5.1V)
Output Current
Io(max.)=100mA
High Precision Output
Vo±1.0%
Low Dropout Voltage
0.10V typ. (Io=60mA)
ON/OFF Control
(Active High)
Internal Short Circuit Current Limit
Internal Thermal Overload Protection
Bipolar Technology
Package Outline
SOT-23-5
PIN CONFIGURATION
5
4
PACKAGE OUTLINE
NJM2831F
1 2 3
1. CONTROL
2. GND
3. NC
4. V
OUT
5. V
IN
NJM2831
EQUIVALENT CIRCUIT
V
IN
Control
Bandgap
Reference
Thermal
Protection
V
OUT
GND
Ver.2008-12-02
-1-
NJM2831
RATINGS
+20
+20(*1)
500(*2)
Power Dissipation
P
D
SOT-23-5
MW
250(*3)
Operating Temperature
Topr
-40∼+85
°C
Storage Temperature
Tstg
-40∼+150
°C
(*1): When input voltage is less than +20V, the absolute maximum control voltage is equal to the input voltage.
(*2): Mounted on glass epoxy board based on EIA/JEDEC. (114.3x76.2x1.6mm: 2Layers)
(*3): Device itself.
ELECTRICAL CHARACTERISTICS
(V
IN
= Vo+1V, C
IN
=0.1µF, Co=1.0µF (2.8V<Vo≤5V:Co=2.2µF, Vo≤2.8V: Co=4.7µF),Ta=25°C)
PARAMETER
SYMBOL
TEST CONDITION
MIN.
TYP.
Output Voltage
Vo
Io=30mA
-1.0%
−
120
Vo≤5V Version
−
Io=0mA,
Quiescent Current
I
Q
135
5V<Vo≤10V Version
−
expect Icont
150
10V<Vo≤15V Version
−
Quiescent Current
I
Q(OFF)
V
CONT
=0V
−
−
at Control OFF
Output Current
Io
Vo-0.3V
100
130
V
IN
=Vo+1V
∼
Vo+6V(Vo≤12V Version)
Line Regulation
−
−
∆Vo/∆V
IN
V
IN
=Vo+1V
∼
18V(Vo>12V Version),
Io=30mA
Load Regulation
∆Vo/∆Io
Io=0
∼
60mA
−
−
Io=60mA
0.10
Dropout Voltage(*4)
−
∆V
I−O
ein=200mVrms,f=1kHz,Io=10mA,
Ripple Rejection
RR
75
−
Vo=3V Version
Average Temperature
Coefficient of Output
∆Vo/∆Ta
Ta=0
∼
85°C, Io=10mA
−
±
50
Voltage
f=10Hz
∼
80kHz, Io=10mA
45
Output Noise Voltage
V
NO
−
Vo=3V Version
Control Current
Icont
V
CONT
=1.6V
3
Control Voltage for
V
CONT(ON)
1.6
−
ON-state
Control Voltage for
V
CONT(OFF)
−
−
OFF-state
Input Voltage
V
IN
−
−
(*4): The above specification is a common specification for all output voltages.
Therefore, it may be different from the individual specification for a specific output voltage.
ABSOLUTE MAXIMUM RATINGS
PARAMETER
SYMBOL
Input Voltage
V
IN
Control Voltage
V
CONT
(Ta=25°C)
UNIT
V
V
MAX.
+1.0%
180
195
210
100
−
0.10
0.03
0.18
−
−
−
12
−
0.6
18
UNIT
V
µA
µA
µA
nA
mA
%/V
%/mA
V
dB
ppm/
°C
µVrms
µA
V
V
V
Ver.2008-12-02
-3-
NJM2831
2
In use of ON/OFF CONTROL:
V
IN
V
IN
V
OUT
V
OUT
0.1µF
R
NJM2831
1.0µF
*6
CONTROL
GND
*6
2.8V<Vo
≤
5V version: Co=2.2
µ
F
Vo≤2.8V version: Co=4.7µF
State of control terminal:
•“H”→
output is enabled.
•“L”
or “open”
→
output is disabled.
In the case of using a resistance "R" between V
IN
and control.
The current flow into the control terminal while the IC is ON state (I
CONT
) can be reduced when a pull up resistance
"R" is inserted between V
IN
and the control terminal.
The minimum control voltage for ON state (V
CONT (ON)
) is increased due to the voltage drop caused by I
CONT
and the
resistance "R". The I
CONT
is temperature dependence as shown in the "Control Current vs. Temperature"
characteristics. Therefore, the resistance "R" should be carefully selected to ensure the control voltage exceeds the
V
CONT (ON)
over the required temperature range.
Input Capacitance C
IN
Input capacitance C
IN
is required to prevent oscillation and reduce power supply ripple for applications with high
power supply impedance or a long power supply line.
Use the C
IN
value of 0.1µF greater to avoid the problem.
C
IN
should connect between GND and V
IN
as short as possible.
Output Capacitance C
O
Output capacitor (Co) is required for a phase compensation of the internal error amplifier. The capacitance and the
equivalent series resistance (ESR) influences stability of the regulator.
This product is designed to work with a low ESR capacitor for the Co; however, use of recommended capacitance or
greater value is essential for stable operation.
Use of a smaller Co may cause excess output noise or oscillation of the regulator due to lack of the phase
compensation.
Therefore, use Co with the recommended capacitance or greater value and connect between Vo terminal and GND
terminal with minimal wiring. The recommended capacitance depends on the output voltage. Low voltage regulator
requires greater value of the Co. Thus, check the recommended capacitance for each output voltage.
Use of a greater Co reduces output noise and ripple output, and also improves transient response of the output
voltage against rapid load change.
Ver.2008-12-02
-5-
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