IRU1117-18(PbF)
1
www.irf.com
TYPICAL APPLICATION
DESCRIPTION
The IRU1117-18 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
IRU1117-18 is guaranteed to have <1.2V dropout at full
load current making it ideal to provide well regulated with
3.8V input supply. The IRU1117-18 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 1.8V REGULATOR
Figure 1 - Typical set-up of the IRU1117-18 in a 3.3V to 1.8V regulator application.
Data Sheet No. PD94137 revA
FEATURES
Guaranteed < 1.2V Dropout at 800mA Load
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
APPLICATIONS
Low Voltage IC Supply Applications
PC Clock Supply Voltage
3.3V
1.8V / 800mA
C1
10uF
C2
10uF
IRU1117-18
3
1
2
V
IN
V
OUT
Gnd
PACKAGE ORDER INFORMATION
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 125 IRU1117-18CD IRU1117-18CP IRU1117-18CS IRU1117-18CY
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 125 Not available Not available IRU1117-18CSPbF Not available
Leadfree Part
Basic Part (Non-Lead Free)
2
IRU1117-18(PbF)
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 125C
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)
Unless otherwise specified, these specifications apply over C
IN
=1F, V
IN
=5V, C
OUT
=10F, and T
J
=0 to 125 C.
Typical values refer to T
J
=25 C.
ELECTRICAL SPECIFICATIONS
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 C
Io=10mA
Io=10mA, 4.75V<V
IN
<7V
10mA<Io<800mA
Io=1A
Io=800mA
Vo=100mV
30ms Pulse, Io=800mA
f=120Hz, Co=25F Tantalum,
Io=0.5A
Io=10mA
T
J
=125 C, 1000Hrs
T
J
=25 C, 10Hz<f<10KHz
1.782
1.764
1.1
1.800
1.800
1.2
1.1
0.01
70
0.5
0.3
0.003
1.818
1.896
7
17
1.3
1.2
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
IRU1117-18(PbF)
3
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 IRU1117-18.
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
+
+
4
IRU1117-18(PbF)
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
K
M
Q
7
N
P
R
S
R1
L
C
E
J
L
O
R0.31 TYP
R0.51 TYP
2.286 BSC
IRU1117-18(PbF)
5
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
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
3.30
5.08 NOM
A
E
M
L
N
U
C
B
K
P
V
H
G
D
R
L
C
A1
G1
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