IRU1117-25
1
Rev. 1.5
02/04/03
www.irf.com
TYPICAL APPLICATION
DESCRIPTION
The IRU1117-25 is a low dropout three-terminal fixed out-
put regulator with minimum of 800mA output current ca-
pability. This product is specifically designed to provide
well regulated supply for low voltage IC applications as
well as generating clock supply for PC applications. The
IRU1117-25 is guaranteed to have <1.2V dropout at full
load current making it ideal to provide well regulated with
3.8V input supply. The IRU1117-25 is specifically de-
signed to be stable with low cost aluminum capacitors
while maintaining stability with low ESR tantalum caps.
800mA LOW DROPOUT POSITIVE
FIXED 2.5V REGULATOR
Figure 1 - Typical application of IRU1117-25 in a 5V to 2.5V regulator.
Data Sheet No. PD94141
T
J
(C) 2-PIN PLASTIC 2-PIN PLASTIC 8-PIN PLASTIC 3-PIN PLASTIC
TO-252 (D-Pak) Ultra Thin-Pak
TM
(P) SOIC (S) SOT-223 (Y)
0 To 150 IRU1117-25CD IRU1117-25CP IRU1117-25CS IRU1117-25CY
PACKAGE ORDER INFORMATION
Guaranteed < 1.2V Dropout at 800mALoad
Current
Fast Transient Response
1% Voltage Reference Initial Accuracy
Built-In Thermal Shutdown
Available in SOT-223, D-Pak, Ultra Thin-Pak
TM
and 8-Pin SOIC Surface-Mount Packages
FEATURES
APPLICATIONS
Low Voltage IC Supply Applications
PC Clock Supply Voltage
5V
2.5V / 800mA
C1
10uF
C2
10uF
IRU1117-25
3
1
2
V
I N
V
O U T
Gnd
2
Rev. 1.5
02/04/03
IRU1117-25
www.irf.com
ABSOLUTE MAXIMUM RATINGS
Input Voltage (V
IN
) .................................................... 7V
Power Dissipation ..................................................... Internally Limited
Storage Temperature Range ...................................... -65C To 150C
Operating Junction Temperature Range ..................... 0C To 150C
PACKAGE INFORMATION
2-PIN PLASTIC TO-252 (D-Pak) 2-PIN ULTRA THIN-PAK
TM
(P) 8-PIN PLASTIC SOIC (S) 3-PIN PLASTIC SOT-223 (Y)
ELECTRICAL SPECIFICATIONS
Unless otherwise specified, these specifications apply over C
IN
=1
m
F, V
IN
=5V, C
OUT
=10
m
F, and T
J
=0 to 125
8
C.
Typical values refer to T
J
=25
8
C.
Note 1: Low duty cycle pulse testing with Kelvin connections is required in order to maintain accurate data.
Note 2: Dropout voltage is defined as the minimum differential voltage between V
IN
and V
OUT
required to maintain
regulation at V
OUT
. It is measured when the output voltage drops 1% below its nominal value.
Output Voltage
Line Regulation
Load Regulation (Note 1)
Dropout Voltage (Note 2)
Current Limit
Thermal Regulation
Ripple Rejection
Temperature Stability
Long Term Stability
RMS Output Noise
PARAMETER
SYM TEST CONDITION MIN TYP MAX UNITS
Io=10mA, T
J
=25
8
C
Io=10mA
Io=10mA, 4.75V<V
IN
<7V
10mA<Io<800mA
Io=1A
Io=800mA
D
Vo=100mV
30ms Pulse, Io=800mA
f=120Hz, Co=25
m
F Tantalum,
Io=0.5A
Io=10mA
T
J
=125
8
C, 1000Hrs
T
J
=25
8
C, 10Hz<f<10KHz
2.475
2.450
1.1
2.500
2.500
1.2
1.1
0.01
70
0.5
0.3
0.003
2.525
2.550
7
17
1.3
1.2
0.02
1
V
mV
mV
V
A
%/W
dB
%
%
%V
O
V
O
JA
=70
C/W for 0.5" Sq pad
JA
=70
C/W for 0.5" Sq pad
JA
=55
C/W for 1" Sq pad
JA
=90
C/W for 0.4" Sq pad
Gnd
Tab is
V
OUT
V
IN
1
3
Gnd
V
IN
1
3
Tab is
V
OUT
Gnd
NC
NC
V
IN
V
OUT
4
3
2
1
5
6
7
8
V
OUT
V
OUT
V
OUT
Gnd
V
OUT
V
IN
Tab is
V
OUT
3
1
2
IRU1117-25
3
Rev. 1.5
02/04/03
www.irf.com
PIN DESCRIPTIONS
Ground pin. This pin must be connected to ground plane using a low inductance short
connection.
The output of the regulator. This pin is also connected to the tab of the package. An output
capacitor must be connected to this pin to insure stability of the regulator.
Input pin of the regulator. Typically a large storage capacitor is connected from this pin to
ground to insure that the input voltage does not sag below the minimum dropout voltage
during the load transient response. This pin must always be 1.3V higher than V
OUT
in order
for the device to regulate properly.
BLOCK DIAGRAM
Figure 2 - Simplified block diagram of the IRU1117-25.
PIN# PIN SYMBOL PIN DESCRIPTION
1
2
3
Gnd
V
OUT
V
IN
V
IN
3
1 Gnd
2 V
OUT
THERMAL
SHUTDOWN
CURRENT
LIMIT
1.25V
+
+
IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105
TAC Fax: (310) 252-7903
Visit us at www.irf.com for sales contact information
Data and specifications subject to change without notice. 02/01
4
Rev. 1.5
02/04/03
IRU1117-25
www.irf.com
(D) TO-252 Package
2-Pin
SYMBOL
A
B
C
D
E
F
G
H
J
K
L
M
N
O
P
Q
R
R1
S
MIN
6.477
5.004
0.686
7.417
9.703
0.635
4.521
&
1.52
2.184
0.762
1.016
5.969
1.016
0
0.534
0.428
MAX
6.731
5.207
0.838
8.179
10.084
0.889
4.623
&
1.62
2.388
0.864
1.118
6.223
1.118
0.102
0.686
0.588
NOTE: ALL MEASUREMENTS
ARE IN MILLIMETERS.
A
B
C
D
F
G
H
45
8
K
M
Q
7
8
N
P
R
S
R1
L
C
E
J
L
O
R0.31 TYP
R0.51 TYP
2.286 BSC
IRU1117-25
5
Rev. 1.5
02/04/03
www.irf.com
(P) Ultra Thin-Pak
TM
2-Pin
NOTE: ALL MEASUREMENTS
ARE IN MILLIMETERS.
SYMBOL
A
A1
B
C
D
E
G
G1
H
K
L
M
N
P
R
U
V
MIN
5.91
5.54
6.02
1.70
0.63
0.17
2.16
4.45
9.42
0.76
0.02
0.89
0.25
0.94
2
8
2.92
MAX
6.17
5.79
6.27
2.03
0.79
0.33
2.41
4.70
9.68
1.27
0.13
1.14
0.25
1.19
6
8
3.30
5.08 NOM
A
E
M
L
N
U
C
B
K
P
V
H
G
D
R
L
C
A1
G1
PDF 
ZIP