NJM2857
LOW DROPOUT VOLTAGE REGULATOR
GENERAL DESCRIPTION
The NJM2857 is a low dropout voltage regulator.
This product has Reverse Current Protection without external SBD
Advanced Bipolar technology achieves low noise, high ripple
rejection and high supply voltage.
1.5A output current capacity, 4.7µF small decoupling capacitor,
built-in noise bypass capacitor make the NJM2857 suitable for
various applications.
FEATURES
High Ripple Rejection
80dB typ. (f=1kHz, Vo=3V Version)
Output Noise Voltage
Vno=55µVrms typ. (Vo=3V Version)
Output capacitor with ceramic capacitor
Output Current
Io(max.)=1.5A
High Precision Output
Vo
±1.0%
Low Dropout Voltage
0.20V typ. (Io=1A)
ON/OFF Control
Internal Reverse Current Protection
Internal Thermal Overload Protection
Internal Over Current Protection
Bipolar Technology
Package Outline
TO-252-5
PIN CONFIGURATION
3
PACKAGE OUTLINE
NJM2857DL3
123 45
1.CONTROL
2.V
IN
3.GND
4.Vo
5.N.C.
NJM2857DL3
EQUIVALENT CIRCUIT
V
IN
Reverse
Current
Protection
Thermal
Protection
V
OUT
CONTROL
Bandgap
Reference
Current
Limit
GND
Ver.2010-02-08
-1-
NJM2857
OUTPUT VOLTAGE
Device Name
V
OUT
NJM2857DL3-15
1.5V
NJM2857DL3-25
2.5V
NJM2857DL3-03
3.0V
NJM2857DL3-33
3.3V
NJM2857DL3-05
5.0V
Output voltage options available : 1.5 ~ 5.0V (0.1V step)
ABSOLUTE MAXIMUM RATINGS
PARAMETER
SYMBOL
Input Voltage
V
IN
Control Voltage
V
CONT
Output Terminal Voltage
V
o.max
(Ta=25°C)
UNIT
V
V
V
RATINGS
+10
+10
Vo+1
1190(*1)
Power Dissipation
P
D
mW
3125(*2)
Operating Temperature
Topr
-40
∼
+85
°C
Storage Temperature
Tstg
-40
∼
+150
°C
(*1) : Mounted on glass epoxy board. (76.2x 114.3x1.6mm:EIA/JDEC standard size, 2Layers, copper area 100mm
2
)
(*2) : Mounted on glass epoxy board. (76.2x 114.3x1.6mm:EIA/JDEC standard size, 4Layers, copper area 100mm
2
)
(4Layers inner foil : 74.2 x 74.2mm Applying a thermal beer hall to a board based on JEDEC standard JESD51-5)
Operating voltage
V
IN
=+2.6V(In case of Vo<2.4V) ~ +8V
-2-
Ver.2010-02-08
NJM2857
ELECTRICAL CHARACTERISTICS
(V
IN
=Vo+1V(Vo<1.6V: V
IN
=2.6V), C
IN
=1.0µF, Co=4.7µF(1.7V<Vo≤2.4V: Co=10µF, Vo≤1.7V: Co=22uF), Ta=25°C)
PARAMETER
SYMBOL
TEST CONDITION
MIN.
TYP.
MAX.
UNIT
Output Voltage
Vo
Io=30mA
-1.0%
-
+1.0%
V
Input Voltage
V
IN
-
-
8
V
Quiescent Current
I
Q
Io=0mA
-
500
750
µA
Quiescent Current
V
CONT
=0V
-
-
100
nA
I
Q (OFF)
at Control OFF
Output Current
Io
1500 2000
-
mA
Vo×0.9V
V
IN
=Vo+1V
∼
Vo+6V (Vo≤2V),
-
-
0.10
%/V
Line Regulation
∆Vo/∆V
IN
V
IN
=Vo+1V
∼
+8V(Vo>2V),
Io=30mA
Load Regulation
-
-
0.003 %/mA
∆Vo/∆Io
Io=0
∼
1500mA
Io=1000mA
-
0.20
0.30
V
Dropout Voltage(*1)
∆V
I -O
Vo=1.5V
-
86
-
-
82
-
ein=200mVrms, Vo=2.5V
Ripple Rejection(*2)
RR
f=1kHz,
dB
Vo=3.0V
-
80
-
Io=10mA
Vo=3.3V
-
79
-
Vo=5.0V
-
78
-
Average Temperature
Coefficient of Output
-
-
∆Vo/∆Ta
Ta=0
∼
85°C, Io=10mA
±
50
ppm/°C
Voltage
Vo=1.5V
-
26
-
Vo=2.5V
-
41
-
f=10Hz
∼
80kHz,
Output Noise Voltage
V
NO
47
Vo=3.0V
-
-
µVrms
Io=10mA,
51
Vo=3.3V
-
-
69
Vo=5.0V
-
-
Control Current
I
CONT
V
CONT
=1.6V
-
3
12
µA
Control Voltage for ON-state
V
CONT(ON)
1.6
-
-
V
Control Voltage for OFF-state
V
CONT(OFF)
-
-
0.6
V
(*1): The output voltage excludes under 2.4V
(*2): Vo>2.0V:V
IN
=Vo+1V, Vo≤2.0V:V
IN
=3.0V
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.
POWER DISSIPATION vs. AMBIENT TEMPERATURE
NJM2857DL3 PowerDissipation
(Topr=-40~+85°C,Tj=150°C)
3500
Power Dissipation P
D
(mW)
3000
2500
2000
1500
1000
500
0
-50
on 4 layers board
on 2 layers board
-25
0
25
50
75
100
Temperature : Ta(°C)
Ver.2010-02-08
-3-
NJM2857
TEST CIRCUIT
A
V
IN
I
IN
V
IN
NJM2857
V
OUT
(*3)
1.0µF
4.7µF
(ceramic)
I
OUT
V
V
OUT
A
V
V
CONT
I
CONT
CONTROL
GND
(*3)
1.7V<Vo≤2.4V version:Co=10µF (ceramic)
Vo≤1.7V version:Co=22µF (ceramic)
-4-
Ver.2010-02-08
NJM2857
TYPICAL APPLICATIONS
1
In the case where ON/OFF Control is not required:
V
IN
V
IN
NJM2857
R
CONTROL
V
OUT
(*4)
V
OUT
4.7µF
1.0µF
GND
(*4)
1.7V<Vo≤2.4V version: Co=10µF
Vo≤1.7V version:Co=22µF
Connect control terminal to V
IN
terminal
2
In use of ON/OFF CONTROL:
V
IN
V
IN
NJM2857
R
CONTROL
V
OUT
(*4)
V
OUT
4.7µF
1.0µF
GND
(*4)
1.7V<Vo≤2.4V version: Co=10µF
Vo≤1.7V version:Co=22µF
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.
Ver.2010-02-08
-5-
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