Preliminary
FEATURES
•
Guaranteed Output Voltage Accuracy within 2%
•
Fast Transient Response
•
Load Regulation : 0.1% Typ.
•
Line Regulation : 0.03% Typ.
•
Low Dropout Voltage : 1.1V Typ. at I
OUT
=1A
•
Current Limit : 1A Typ. at T
J
=25
°C
•
On-chip Thermal Limiting : 150
°C
Typ.
•
Adjustable Output : 1.25~10.7V
•
Standard 3-pin SOT-223 Power Packages
APPLICATIONS
•
PC peripheral
•
Low Voltage Logic Supplies
•
Post Regulator for Switching Power Supply
Package Information
DESCRIPTION
EP1117
1A Low Dropout Regulator
The EP1117 is a low dropout three-terminal
adjustable or fixed-voltage regulator with 1A
output
current
capability.
The
EP1117
is
available in an adjustable version, with output
ranging from 1.25V to 10.7V and fixed output
voltages of 1.8V, 2.5V and 3.3V. Dropout voltage
is guaranteed at a maximum of 1.3V at 1A.
On-chip thermal limiting provides protection
against any combination of overload that would
create excessive junction temperatures. The
EP1117 is available in the industry standard
3-pin the low profile surface mount SOT-223
power
packages
which
can
be
used
in
applications where space is limited.
Rev.01
1/8
Preliminary
Absolute Maximum Rating
(Note1)
Symbol
V
I
Parameter
Input Voltage EP1117-adj, EP1117-33
EP1117-25, EP1117-18
Operating Junction Temperature Range
T
J
Control Section
Power Transistor
T
STG
T
L
Storage Temperature Range
Lead Temperature (Soldering, 10 second)
0 to 125
0 to 150
-65 to +150
260
Rating
(Note2)
15
9
EP1117
Unit
V
°C
°C
°C
Note: 1. Absolute Maximum Ratings are those values beyond which the life of a device may be impaired.
Note: 2.The values here show the absolute maximum rating, and for normal usage please refer the test
condition in Electrical Characteristics Table.
Electrical Characteristics
(Note3)
:
Unless otherwise noted, these specifications apply over C
IN
= 10μF, C
OUT
= 10μF, and T
A
=0 to 70°C. Typical
values refer to T
A
=25°C.
Symbol
V
REF
Parameter
Reference
Voltage
Output Voltage
EP1117-18
T
J
= 0~125°C,
0≤I
OUT
≤1.5A,
3.25V≤ V
IN
≤9V,
V
OUT
EP1117-25
T
J
= 0~125°C,
0≤ I
OUT
≤
1A, 3.95V≤ V
IN
≤9V
EP1117-33
T
J
= 0~125°C, 0≤I
OUT
≤1A,
4.75V≤V
IN
≤12V
Line Regulation
EP1117-adj
REG
LINE
I
OUT
=10mA,
1.5V≤(V
IN
-V
OUT
)≤10.75V
EP1117-18
EP1117-25
EP1117-33
Load Regulation
EP1117
REG
LOAD
EP1117-18
EP1117-25
EP1117-33
(V
IN
-V
OUT
)=3V, 0≤ I
OUT
≤1A
V
IN
= 3.25V, 0≤ I
OUT
≤1A
V
IN
= 3.95V, 0≤ I
OUT
≤1A
V
IN
= 4.75V, 0≤ I
OUT
≤1A
(Note4)
(Note4)
(Note4)
(Note4)
(Note4)
Conditions
T
J
= 0~125°C, 10mA≤ I
OUT
≤1A,
1.4V≤ (V
IN
-V
OUT
)
≤10.75V
Min.
1.225
Typ.
1.250
Max.
1.275
Unit
V
1.764
1.800
1.836
2.450
2.500
2.550
V
3.235
3.300
3.365
0.03
1
1
1
0.2
6
6
6
%
mV
I
OUT
= 0A, 3.25V≤V
IN
≤9V
I
OUT
= 0A, 3.95V≤ V
IN
≤9V
I
OUT
= 0A, 4.75V≤V
IN
≤12V
0.1
1
1
1
0.4
10
10
10
(Note4)
(Note4)
(Note4)
%
mV
Rev.01
2/8
Preliminary
I
OUT
= 100mA
V
D
Dropout Voltage
I
OUT
= 500mA
I
OUT
= 1A
I
LIMIT
I
ADJ
Current Limit
Adjust Pin
Current
Adjust Pin
Current Change
Minimum Load
Current
Ripple Rejection
Thermal
Regulation
Temperature
Stability
Long -Term
Stability
RMS Output
Noise
Thermal
Resistance
Over
OT
Temperature
Point
Quiescent
Current
I
Q
EP1117-18
EP1117-25
EP1117-33
and characterization.
V
IN
≤9V
V
IN
≤9V
V
IN
≤12V
5.5
5.5
5.5
150
T
J
= 25°C, 10Hz≤F≤10kHz,
(% of V
OUT
)
Junction to Case, at Tab Junction to
Ambient
T
J
= 125°C, 1000Hrs.
f
RIPPLE
=120Hz, V
RIPPLE
= 1VP-P,
(V
IN
-V
OUT
) = 3V
T
J
= 25°C, 30ms Pulse
60
10mA≤ I
OUT
≤1A,
1.4V≤ (V
IN
-V
OUT
)
≤10.75V
(V
IN
-V
OUT
) = 10.75V
(Note6)
(Note5)
(Note5)
EP1117
1
1.05
1.1
1000
60
120
1.1
1.2
1.3
mA
μA
V
(Note5)
(V
IN
-V
OUT
) = 5V, T
J
= 25°C
(V
IN
-V
OUT
) = 3V, I
OUT
= 10mA
ΔI
ADJ
0.2
5
μA
I
O
1.7
mA
PSRR
75
dB
T
R
0.01
0.02
%/ W
T
S
0.5
%
L
S
0.3
%
V
N
0.003
%
θ
th
15
°C/ W
°C
10
10
10
mA
Note 3. 100% production test at +25°C. Specifications over the temperature range are guaranteed by design
Note 4: See thermal regulation specifications for changes in output voltage due to heating effects. Load line
regulations are measured at a constant junction temperature by low duty cycle pulse testing.
Note 5: Dropout voltage is specified over the full output current range of the device. Dropout voltage is defined
as the minimum input/output differential measured at the specified output current. Test points and limits
are also shown on the Dropout Voltage curve.
Note 6: Minimum load current is defined as the minimum output current required to maintain regulation.
Rev.01
3/8
Preliminary
Typical Performance Characteristics
Dropout Voltage vs. Output Current
EP1117
Output Voltage vs. Input Voltage
Input Current vs. Input Voltage
Current Limit vs. Input Voltage
Functional Block Diagram
Rev.01
4/8
Preliminary
APPLICATIONS INFORMATION
1.25V to 10.7V Adjustable Regulator
EP1117
Fixed Voltage Model—Basic Connections.
* Needed if device is far from filter capacitors
V
out
=
1.250
V
×
R
1
+
R
2
R
1
Output Voltage
The EP1117 develops a 1.25V reference voltage between the output and the adjust terminal. By placing a
resistor between these two terminals, a constant Current is caused to flow through R1 and down through R2 to
set the overall output voltage. Normally this current is chosen to be the specified minimum load current of 10mA.
For fixed voltage devices R1 and R2 are included in the device.
⎛
R
2
⎞
V
out
=
V
REF
⎜
1
+
⎟ +
I
ADJ
R
2
⎝
R
1
⎠
Figure 1. Basic Adjustable Regulator
Load Regulation
When the adjustable regulator is used, load regulation will be limited by the resistance of the wire
connecting the regulator to the load. The datasheet specification for load regulation is measured at
the output pin of the EP1117. Best load regulation is obtained when the top of the resistor divider
(R1) is tied directly to the output pin of the device, not to the load. For fixed voltage devices, the top
of R1 is internally connected to the output, and the ground pin can be connected to low side of the
load. If R1 were connected to the load, RP is multiplied by the divider ratio, the effective resistance
between the regulator and the load would be: Rp X (1+ R2/R1 ), where Rp is Parasitic Line
Resistance.
Rev.01
5/8
