LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
800mA Low Dropout
Positive Regulators Adjustable
and Fixed 2.85V, 3.3V, 5V
FEATURES
DESCRIPTION
n
The LT®1117 is a positive low dropout regulator designed
to provide up to 800mA of output current. The device is
available in an adjustable version and fixed output voltages
of 2.85V, 3.3V and 5V. The 2.85V version is designed
specifically to be used in Active Terminators for the SCSI
bus. All internal circuitry is designed to operate down to 1V
input to output differential. Dropout voltage is guaranteed
at a maximum of 1.2V at 800mA, decreasing at lower load
currents. On chip trimming adjusts the reference/output
voltage to within ± 1%. Current limit is also trimmed in
order to minimize the stress on both the regulator and the
power source circuitry under overload conditions.
n
n
n
n
n
n
Space Saving SOT-223 Surface Mount Package
3-Terminal Adjustable or Fixed 2.85V, 3.3V, 5V
Output Current of 800mA
Operates Down to 1V Dropout
Guaranteed Dropout Voltage at Multiple Current Levels
0.2% Line Regulation Max
0.4% Load Regulation Max
APPLICATIONS
n
n
n
n
n
Active SCSI Terminators
High Efficiency Linear Regulators
Post Regulators for Switching Supplies
Battery Chargers
5V to 3.3V Linear Regulators
L, LT, LTC, LTM, Linear Technology, OPTI-LOOP and the Linear logo are registered trademarks
of Linear Technology Corporation. UltraFast is a trademark of Linear Technology Corporation. All
other trademarks are the property of their respective owners.
The low profile surface mount SOT-223 package allows the
device to be used in applications where space is limited. The
LT1117 requires a minimum of 10μF of output capacitance
for stability. Output capacitors of this size or larger are
normally included in most regulator designs.
Unlike PNP type regulators where up to 10% of the output
current is wasted as quiescent current, the quiescent current
of the LT1117 flows into the load, increasing efficiency.
TYPICAL APPLICATION
Active Terminator for SCSI-2 Bus
Dropout Voltage (VIN – VOUT)
1.4
110Ω
–40°C ≤ TJ < 0°C
1.2
IN
4.75V TO
5.25V
10μF
18 TO 27
LINES
OUT
GND
+
110Ω
+
22μF
110Ω
1117 TA01
DROPOUT VOLTAGE (V)
110Ω
LT1117-2.85
0°C ≤ TJ ≤ 125°C
1.0
TJ = 25°C
0.8
TJ = 125°C
0.6
0.4
0.2
INDICATES GUARANTEED TEST POINT
0
0
100 200 300 400 500 600 700 800
OUTPUT CURRENT (mA)
1117 TA02
1117fd
1
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Input Voltage
Operating Voltage
LT1117, LT1117-3.3, LT1117-5 .........................15V
LT1117-2.85 .....................................................10V
Surge Voltage
LT1117, LT1117-3.3, LT1117-5 .........................20V
Operating JunctionTemperature Range
C Grade .................................................. 0°C to 125°C
I Grade ...............................................– 40°C to 125°C
Storage Temperature Range...................–65°C to 150°C
Lead Temperature ....................(See Soldering Methods)
PIN CONFIGURATION
FRONT VIEW
FRONT VIEW
TAB IS
VOUT
3
IN
2
OUT
1
ADJ/GND
TAB IS
VOUT
ST PACKAGE
3-LEAD PLASTIC SOT-223
TJMAX = 125°C, θJC = 15°C/W
3
IN
2
OUT
1
ADJ/GND
M PACKAGE
3-LEAD PLASTIC DD-PAK
TJMAX = 125°C, θJC = 10°C/W
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT1117CST#PBF
LT1117CST#TRPBF
1117
3-Lead Plastic SOT-223
0°C to 125°C
LT1117IST#PBF
LT1117IST#TRPBF
1117I
3-Lead Plastic SOT-223
–40°C to 125°C
LT1117CST-2.85#PBF
LT1117CST-2.85#TRPBF
11172
3-Lead Plastic SOT-223
0°C to 125°C
LT1117IST-2.85#PBF
LT1117IST-2.85#TRPBF
1117I2
3-Lead Plastic SOT-223
–40°C to 125°C
LT1117CST-3.3#PBF
LT1117CST-3.3#TRPBF
11173
3-Lead Plastic SOT-223
0°C to 125°C
LT1117IST-3.3#PBF
LT1117IST-3.3#TRPBF
1117I3
3-Lead Plastic SOT-223
–40°C to 125°C
LT1117CST-5#PBF
LT1117CST-5#TRPBF
11175
3-Lead Plastic SOT-223
0°C to 125°C
LT1117IST-5#PBF
LT1117IST-5#TRPBF
1117I5
3-Lead Plastic SOT-223
–40°C to 125°C
LT1117CM#PBF
LT1117CM#TRPBF
LT1117CM
3-Lead Plastic DD-PAK
0°C to 125°C
LT1117CM-2.85#PBF
LT1117CM-2.85#TRPBF
LT1117CM-2.85
3-Lead Plastic DD-PAK
0°C to 125°C
LT1117CM-3.3#PBF
LT1117CM-3.3#TRPBF
LT1117CM-3.3
3-Lead Plastic DD-PAK
0°C to 125°C
LT1117CM-5#PBF
LT1117CM-5#TRPBF
LT1117CM-5
3-Lead Plastic DD-PAK
0°C to 125°C
1117fd
2
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
ORDER INFORMATION
LEAD BASED FINISH
TAPE AND REEL
PART MARKING
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT1117CST
LT1117CST#TR
1117
3-Lead Plastic SOT-223
0°C to 125°C
LT1117IST
LT1117IST#TR
1117I
3-Lead Plastic SOT-223
–40°C to 125°C
LT1117CST-2.85
LT1117CST-2.85#TR
11172
3-Lead Plastic SOT-223
0°C to 125°C
LT1117IST-2.85
LT1117IST-2.85#TR
1117I2
3-Lead Plastic SOT-223
–40°C to 125°C
LT1117CST-3.3
LT1117CST-3.3#TR
11173
3-Lead Plastic SOT-223
0°C to 125°C
LT1117IST-3.3
LT1117IST-3.3#TR
1117I3
3-Lead Plastic SOT-223
–40°C to 125°C
LT1117CST-5
LT1117CST-5#TR
11175
3-Lead Plastic SOT-223
0°C to 125°C
LT1117IST-5
LT1117IST-5#TR
1117I5
3-Lead Plastic SOT-223
–40°C to 125°C
LT1117CM
LT1117CM#TR
LT1117CM
3-Lead Plastic DD-PAK
0°C to 125°C
LT1117CM-2.85
LT1117CM-2.85#TR
LT1117CM-2.85
3-Lead Plastic DD-PAK
0°C to 125°C
LT1117CM-3.3
LT1117CM-3.3#TR
LT1117CM-3.3
3-Lead Plastic DD-PAK
0°C to 125°C
LT1117CM-5
LT1117CM-5#TR
LT1117CM-5
3-Lead Plastic DD-PAK
0°C to 125°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TJ = 25°C.
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Reference Voltage
LT1117
IOUT = 10mA, (VIN – VOUT) = 2V, TJ = 25°C
10mA ≤ IOUT ≤ 800mA, 1.4V ≤ (VIN – VOUT) ≤ 10V
l
1.238
1.225
1.250
1.250
1.262
1.270
V
V
Output Voltage
LT1117-2.85
IOUT = 10mA, VIN = 4.85V, TJ = 25°C
0 ≤ IOUT ≤ 800mA, 4.25V ≤ VIN ≤ 10V
0 ≤ IOUT ≤ 500mA, VIN = 3.95V
l
l
2.820
2.790
2.790
2.850
2.850
2.850
2.880
2.910
2.910
V
V
V
LT1117-3.3
IOUT = 10mA, VIN = 5V, TJ = 25°C
0 ≤ IOUT ≤ 800mA, 4.75V ≤ VIN ≤ 10V
l
3.267
3.235
3.300
3.300
3.333
3.365
V
V
LT1117-5
IOUT = 10mA, VIN = 7V, TJ = 25°C
0 ≤ IOUT ≤ 800mA, 6.5V ≤ VIN ≤ 12V
l
4.950
4.900
5.000
5.000
5.050
5.100
V
V
Line Regulation
LT1117
LT1117-2.85
LT1117-3.3
LT1117-5
IOUT = 10mA, 1.5V ≤ VIN – VOUT ≤ 15V (Note 2)
IOUT = 0mA, 4.25V ≤ VIN ≤ 10V (Note 2)
IOUT = 0mA, 4.75V ≤ VIN ≤ 15V (Note 2)
IOUT = 0mA, 6.5V ≤ VIN ≤ 15V (Note 2)
l
l
l
l
0.035
1
1
1
0.2
6
6
10
%
mV
mV
mV
Load Regulation
LT1117
LT1117-2.85
LT1117-3.3
LT1117-5
(VIN – VOUT) = 3V, 10mA ≤ IOUT ≤ 800mA (Note 2)
VIN = 4.25V, 0 ≤ IOUT ≤ 800mA (Note 2)
VIN = 4.75V, 0 ≤ IOUT ≤ 800mA (Note 2)
VIN = 6.5V, 0 ≤ IOUT ≤ 800mA (Note 2)
l
l
l
l
0.1
1
1
1
0.4
10
10
15
%
mV
mV
mV
IOUT = 100mA, 0°C ≤ TJ ≤ 125°C (Note 3)
IOUT = 500mA, 0°C ≤ TJ ≤ 125°C (Note 3)
IOUT = 800mA, 0°C ≤ TJ ≤ 125°C (Note 3)
1.00
1.05
1.10
1.10
1.15
1.20
V
V
V
IOUT = 100mA, – 40°C ≤ TJ < 0°C (Note 3)
IOUT = 500mA, – 40°C ≤ TJ < 0°C (Note 3)
IOUT = 800mA, – 40°C ≤ TJ < 0°C (Note 3)
1.00
1.05
1.10
1.20
1.25
1.30
V
V
V
950
1200
mA
1.7
5
mA
Dropout Voltage
(VIN – VOUT) = 5V, TJ = 25°C
Current Limit
Minimum Load Current
LT1117
(VIN – VOUT) = 15V (Note 4)
800
l
1117fd
3
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TJ = 25°C.
PARAMETER
Quiescent Current
CONDITIONS
MIN
Thermal Regulation
TA = 25°C, 30ms Pulse
Ripple Rejection
fRIPPLE = 120Hz, (VIN – VOUT) = 3V, VRIPPLE = 1VP-P
l
Adjust Pin Current
10mA ≤ IOUT ≤ 800mA, 1.4V ≤ (VIN – VOUT) ≤ 10V
Adjust Pin Current Change
TYP
MAX
5
5
5
10
10
10
mA
mA
mA
0.01
0.1
%/W
l
l
l
VIN ≤ 10V
VIN ≤ 15V
VIN ≤ 15V
LT1117-2.85
LT1117-3.3
LT1117-5
60
75
TA = 125°C, 1000Hrs
RMS Output Noise
(% of VOUT), 10Hz ≤ f ≤ 10kHz
Thermal Resistance
(Junction-to-Case, at Tab)
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: See thermal regulation specification for changes in output voltage
due to heating effects. Load regulation and line regulation are measured at
a constant junction temperature by low duty cycle pulse testing.
dB
l
55
120
μA
l
0.2
5
μA
Temperature Stability
Long Term Stability
UNITS
0.5
%
0.3
%
0.003
%
15
°C/W
Note 3: 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 4: Minimum load current is defined as the minimum output current
required to maintain regulation.
TYPICAL PERFORMANCE CHARACTERISTICS
Minimum Operating Current
(Adjustable Device)
Short-Circuit Current
Load Regulation
1.25
TJ = 125°C
TJ = 25°C
2
TJ = –55°C
1
0
0.10
TJ = 125°C
1.00
OUTPUT VOLTAGE DEVIATION (%)
3
SHORT CIRCUIT CURRENT (A)
MINIMUM OPERATING CURRENT (mA)
4
TJ = 25°C
0.75
0.50
0.25
0
0
10
15
5
INPUT/OUTPUT DIFFERENTIAL (V)
20
1117 G01
0
5
10
INPUT/OUTPUT DIFFERENTIAL (V)
15
1117 G02
ΔILOAD = 800mA
0.05
0
–0.05
–0.10
–0.15
–0.20
–50
–25
0
25
50
75
TEMPERATURE (°C)
100
125
1117 G03
1117fd
4
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
TYPICAL PERFORMANCE CHARACTERISTICS
LT1117 Ripple Rejection
vs Current
100
100
90
VRIPPLE ≤ 3VP-P
VRIPPLE ≤
0.5VP-P
80
(VIN – VOUT) ≥ 3V
70
60
50
40
(VIN – VOUT) ≥ VDROPOUT
30
10
0
RIPPLE REJECTION (dB)
100
VRIPPLE ≤ 3VP-P
60
fRIPPLE = 20kHz
50
40
VRIPPLE ≤ 0.5VP-P
30
20
CADJ = 200μF AT f < 60Hz
CADJ = 25μF AT f > 60Hz
IOUT = 0.5A
10
70
fRIPPLE = 120Hz
0
1k
10k
FREQUENCY (Hz)
0
100k
0.2
0.4
0.6
OUTPUT CURRENT (A)
1117 G04
0
–1.0
–2.0
–50 –25
0.8
0.3
80
60
LT1117-5
Load Transient Response
0.3
CIN = 10μF
COUT = 10μF TANTALUM
VIN = 4.25V
PRELOAD = 0.1A
0.2
0.1
OUTPUT VOLTAGE
DEVIATION (V)
OUTPUT VOLTAGE
DEVIATION (V)
100
70
0
CIN = 10μF
0.2 COUT = 10μF TANTALUM
VIN = 6.5V
0.1 PRELOAD = 0.1A
0
–0.1
–0.1
–0.2
–0.2
20
10
0
–50 –25
0
25 50 75 100 125 150
TEMPERATURE (°C)
LOAD CURRENT
(A)
50
40
30
0.5
0
–0.5
0
10 20 30 40 50 60 70 80 90 100
TIME (μs)
1117 G07
–0.5
0
10 20 30 40 50 60 70 80 90 100
TIME (μs)
1117 G09
60
OUTPUT VOLTAGE
DEVIATION (mV)
CIN = 1μF
40 COUT = 10μF TANTALUM
IOUT = 0.1A
20
0
20
0
–20
–40
–40
5.25
4.25
3.25
20 40 60 80 100 120 140 160 180 200
TIME (μs)
1117 G10
CIN = 1μF
COUT = 10μF TANTALUM
IOUT = 0.1A
40
–20
INPUT VOLTAGE
(V)
OUTPUT VOLTAGE
DEVIATION (mV)
0
LT1117-5
Line Transient Response
60
INPUT VOLTAGE
(V)
0.5
1117 G08
LT1117-2.85
Line Transient Response
0
25 50 75 100 125 150
TEMPERATURE (°C)
1117 G06
LT1117-2.85
Load Transient Response
90
0
1117 G05
Adjust Pin Current
ADJUST PIN CURRENT (μA)
1.0
10
LOAD CURRENT
(A)
RIPPLE REJECTION (dB)
80
20
VOUT = 5V
CADJ = 25μF
COUT = 25μF
90
Temperature Stability
2.0
OUTPUT VOLTAGE CHANGE (%)
LT1117 Ripple Rejection
7.50
6.50
5.50
0
20 40 60 80 100 120 140 160 180 200
TIME (μs)
1117 G11
1117fd
5
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
BLOCK DIAGRAM
IN
+
–
THERMAL
LIMIT
ADJ
GND
OUT
FOR FIXED VOLTAGE DEVICE
1117 BD01
1117fd
6
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
APPLICATIONS INFORMATION
The LT1117 family of 3-terminal regulators are easy to
use. They are protected against short circuit and thermal
overloads. Thermal protection circuitry will shut down the
regulator should the junction temperature exceed 165°C
at the sense point. These regulators are pin compatible
with older 3-terminal adjustable regulators, offer lower
dropout voltage and more precise reference tolerance.
Reference stability over temperature is improved over
older types of regulators.
Stability
The LT1117 family of regulators requires an output
capacitor as part of the device frequency compensation.
A minimum of 10μF of tantalum or 50μF of aluminum
electrolytic is required. The ESR of the output capacitor
should be less than 0.5Ω. Surface mount tantalum
capacitors, which have very low ESR, are available from
several manufacturers.
When using the LT1117 adjustable device, the adjust
terminal can be bypassed to improve ripple rejection.
When the adjust terminal is bypassed, the required value
of the output capacitor increases. The device will require
an output capacitor of 22μF tantalum or 150μF aluminum
electrolytic when the adjust pin is bypassed.
Normally, capacitor values on the order of 100μF are
used in the output of many regulators to ensure good
load transient response with large load current changes.
Output capacitance can be increased without limit and
larger values of output capacitance further improve stability
and transient response.
Protection Diodes
In normal operation, the LT1117 family does not need any
protection diodes. Older adjustable regulators required
protection diodes between the adjust pin and the output
and between the output and input to prevent over stressing
the die. The internal current paths on the LT1117 adjust
pin are limited by internal resistors. Therefore, even with
capacitors on the adjust pin, no protection diode is needed
to ensure device safety under short-circuit conditions.
The adjust pin can be driven, on a transient basis, ± 25V with
respect to the output without any device degradation.
Diodes between input and output are not usually needed.
The internal diode between the output and input pins of
the device can withstand microsecond surge currents of
10A to 20A. Normal power supply cycling can not generate
currents of this magnitude. Only with extremely large output
capacitors, such as 1000μF and larger, and with the input
pin instantaneously shorted to ground can damage occur.
A crowbar circuit at the input of the LT1117 in combination
with a large output capacitor could generate currents large
enough to cause damage. In this case a diode from output
to input is recommended, as shown in Figure 1.
D1
1N4002
(OPTIONAL)
LT1117
VIN
IN
OUT
ADJ
+
+
R1
CADJ
10μF
VOUT
COUT
150μF
R2
1117 F01
Figure 1
1117fd
7
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
APPLICATIONS INFORMATION
Output Voltage
The LT1117 develops a 1.25V reference voltage between the
output and the adjust terminal (see Figure 2). 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.
Because IADJ is very small and constant when compared
to the current through R1, it represents a small error and
can usually be ignored. For fixed voltage devices R1 and
R2 are included in the device.
RP
PARASITIC
LINE RESISTANCE
LT1117
VIN
IN
OUT
ADJ
R1
CONNECT
R1 TO CASE
RL
R2
1117 F03
CONNECT
R2 TO LOAD
Figure 3. Connections for Best Load Regulation
LT1117
VIN
IN
+
VOUT
OUT
ADJ
VREF
R1
IADJ
50μA
R2
VOUT = VREF 1 + — + IADJ R2
R1
For fixed voltage devices the top of R1 is internally Kelvin
connected, and the ground pin can be used for negative
side sensing.
R2
Thermal Considerations
1117 F02
Figure 2. Basic Adjustable Regulator
Load Regulation
Because the LT1117 is a 3-terminal device, it is not possible
to provide true remote load sensing. Load regulation will be
limited by the resistance of the wire connecting the regulator
to the load. The data sheet specification for load regulation
is measured at the output pin of the device. Negative side
sensing is a true Kelvin connection, with the bottom of the
output divider returned to the negative side of the load.
Although it may not be immediately obvious, best load
regulation is obtained when the top of the resistor divider
(R1) is returned directly to the output pin of the device,
not to the load. This is illustrated in Figure 3. Connected
as shown, RP is not multiplied by the divider ratio. If R1
were connected to the load, the effective resistance between
the regulator and the load would be:
RP ×
LT1117 series regulators have internal thermal limiting
circuitry designed to protect the device during overload
conditions. For continuous normal load conditions however,
the maximum junction temperature rating of 125°C must
not be exceeded.
It is important to give careful consideration to all sources
of thermal resistance from junction to ambient. For
the SOT-223 package, which is designed to be surface
mounted, additional heat sources mounted near the device
must also be considered. Heat sinking is accomplished
using the heat spreading capability of the PC board and
its copper traces. The thermal resistance of the LT1117 is
15°C/W from the junction to the tab. Thermal resistances
from tab to ambient can be as low as 30°C/W. The total
thermal resistance from junction to ambient can be as low
as 45°C/W. This requires a reasonable sized PC board with
at least one layer of copper to spread the heat across the
board and couple it into the surrounding air.
R2+R1
,RP = Parasitic Line Resistance
R1
1117fd
8
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
APPLICATIONS INFORMATION
Experiments have shown that the heat spreading copper
layer does not need to be electrically connected to the
tab of the device. The PC material can be very effective at
transmitting heat between the pad area, attached to the
tab of the device, and a ground plane layer either inside
or on the opposite side of the board. Although the actual
thermal resistance of the PC material is high, the Length/
Area ratio of the thermal resistor between layers is small.
The data in Table 1 was taken using 1/16" FR-4 board with
1oz. copper foil. It can be used as a rough guideline in
estimating thermal resistance.
Table 1.
COPPER AREA
TOPSIDE*
BACKSIDE
THERMAL RESISTANCE
BOARD AREA (JUNCTION-TO-AMBIENT)
2500 Sq. mm 2500 Sq. mm
2500 Sq. mm
45°C/W
1000 Sq. mm 2500 Sq. mm
2500 Sq. mm
45°C/W
225 Sq. mm
2500 Sq. mm
2500 Sq. mm
53°C/W
100 Sq. mm
2500 Sq. mm
2500 Sq. mm
59°C/W
1000 Sq. mm 1000 Sq. mm
1000 Sq. mm
52°C/W
1000 Sq. mm 0
1000 Sq. mm
55°C/W
* Tab of device attached to topside copper
The thermal resistance for each application will be
affected by thermal interactions with other components
on the board. Some experimentation will be necessary to
determine the actual value.
The power dissipation of the LT1117 is equal to:
PD = ( VIN – VOUT )( IOUT )
Maximum junction temperature will be equal to:
TJ = TA(MAX) + PD (Thermal Resistance (junction-toambient))
Maximum junction temperature must not exceed 125°C.
Ripple Rejection
The curves for Ripple Rejection were generated using
an adjustable device with the adjust pin bypassed. These
curves will hold true for all values of output voltage. For
proper bypassing, and ripple rejection approaching the
values shown, the impedance of the adjust pin capacitor,
at the ripple frequency, should be < R1. R1 is normally in
the range of 100Ω to 200Ω. The size of the required adjust
pin capacitor is a function of the input ripple frequency. At
120Hz, with R1 = 100Ω, the adjust pin capacitor should
be >13μF. At 10kHz only 0.16μF is needed.
For fixed voltage devices, and adjustable devices without
an adjust pin capacitor, the output ripple will increase as
the ratio of the output voltage to the reference voltage
(VOUT/VREF). For example, with the output voltage equal
to 5V, the output ripple will be increased by the ratio of
5V/1.25V. It will increase by a factor of four. Ripple
rejection will be degraded by 12dB from the value shown
on the curve.
1117fd
9
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
TYPICAL APPLICATIONS
1.2V to 10V Adjustable Regulator
5V Regulator with Shutdown
LT1117
LT1117
VIN
IN
VOUT†
OUT
R1
121Ω
ADJ
+
IN
121Ω
1%
10μF
C2
100μF
R2
1k
5V
OUT
ADJ
+
+
C1*
10μF
VIN
+
100μF
1k
2N3904
TTL
365Ω
1%
1k
* NEEDED IF DEVICE IS FAR FROM FILTER CAPACITORS
R2
†V
—
OUT = 1.25V 1 + R1
( )
1117 TA04
1117 TA03
Remote Sensing
RP
(MAX. DROP 300mV)
LT1117
VIN
IN
OUTPUT
5V
OUT
ADJ
VIN
+
100μF
25Ω
+
7
6
LM301A
1
10μF
121Ω
2
–
4
100pF
5μF
+
365Ω
RL
3 1k
+
8
RETURN
25Ω
RETURN
1117 TA05
Adjusting Output Voltage of Fixed Regulators
Regulator with Reference
LT1117-5
VIN > 12V
IN
+
OUT
GND
10μF
LT1117-5
+
5V TO 10V
100μF
10μF
+
IN
OUT
GND
+
10V
100μF
5VOUT
+
10μF*
VIN > 11.5V
1k
LT1029
1117 TA07
* OPTIONAL IMPROVES RIPPLE REJECTION
1117 TA06
1117fd
10
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
TYPICAL APPLICATIONS
Battery Charger
LT1117
VIN
Battery Backed Up Regulated Supply
LT1117-5
IF
OUT
IN
VOUT
RS
1.25V
VIN
IN
+
GND
10μF
ADJ
R1
50Ω
( )
( )
R2
VOUT – 1.25V 1 + —
R1
IF =
R2
–RS 1 + —
R1
ΔIF
=
ΔVOUT
SELECT FOR
CHARGE RATE
1
( )
R2
–RS 1 + —
R1
+
IN
OUT
GND
10μF
+
100μF
1117 TA09
1117 TA08
Automatic Light Control
LT1117
LT1117
10μF
LT1117-5
IN
+
6.5V
Improving Ripple Rejection
VIN
5.2V LINE
5.0V BATTERY
OUT
OUT
ADJ
* C1 IMPROVES RIPPLE
REJECTION. XC SHOULD BE
≈ R1 AT RIPPLE FREQUENCY
R2
365Ω
1%
5V
R1
121Ω
1%
+
+
IN
+
OUT
ADJ
10μF
+
1.2k
100μF
150μF
C1
10μF
1117 TA11
1117 TA10
High Efficiency Dual Supply
FEEDBACK PATH
MUR410
3.3V OUTPUT (TYPICAL)
+
470μF
LT1117-5
MUR410
IN
+
GND
+
+5V
0.5A
OUT
470μF
10μF
1N4002
10μF
1N4002
+VIN
LT1117-5
MUR410
SWITCHING
REGULATOR
IN
OUT
GND
+
470μF
+
–5V
0.5A
1117 TA12
1117fd
11
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
TYPICAL APPLICATIONS
High Efficiency Dual Linear Supply
L1
285μH
+
MBR360
(HEAT SINK)
2N6667 Q1
(DARLINGTON)
10k
LT1117-5
IN
1000μF
1k
–
GND
2.4k
510k
LT1004-2.5
30k
+
MDA201
5V
0.5A
OUT
V+
+
+
20k*
+
100μF
D11
1N4002
100μF
D2
1N4002
30.1k*
1/2
LT1018
4700μF
–
130VAC
TO 90VAC
L1
285μH
STANCOR
P-8685
(HEAT SINK)
2N6667
(DARLINGTON)
IN
+
MBR360
10k
LT1117-5
1000μF
1k
2.4k
510k
30k
+
MDA201
LT1004-2.5
+
20k*
+
+
–
OUT
GND
30.1k*
1/2
LT1018
4700μF
V–
–
–5V
0.5A
* = 1% FILM RESISTORS
MDA = MOTOROLA
L1 = PULSE ENGINEERING, INC. #PE-92106
1117 TA13
Low Dropout Negative Supply
LT1117-5
VIN
IN
+
10μF
FLOATING INPUT
OUT
GND
+
100μF
VOUT = –5V
1117 TA14
1117fd
12
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
PACKAGE DESCRIPTION
M Package
3-Lead Plastic DD Pak
(Reference LTC DWG # 05-08-1460)
.256
(6.502)
.060
(1.524)
TYP
.060
(1.524)
.390 – .415
(9.906 – 10.541)
.165 – .180
(4.191 – 4.572)
.045 – .055
(1.143 – 1.397)
15°
.060
(1.524)
.183
(4.648)
.330 – .370
(8.382 – 9.398)
+.008
.004 –.004
+0.203
0.102 –0.102
(
.059
(1.499)
)
.095 – .115
(2.413 – 2.921)
.075
(1.905)
.300
(7.620)
+.012
.143 –.020
+0.305
3.632 –0.508
(
BOTTOM VIEW OF DD PAK
HATCHED AREA IS SOLDER PLATED
COPPER HEAT SINK
.050
(1.270)
.100
(2.54)
BSC
)
.013 – .023
(0.330 – 0.584)
.050 ± .012
(1.270 ± 0.305)
.420
.080
.420
.276
.325
.350
.205
.565
.565
.320
.090
.100
.070
RECOMMENDED SOLDER PAD LAYOUT
.090
.100
M (DD3) 0204
.070
RECOMMENDED SOLDER PAD LAYOUT
FOR THICKER SOLDER PASTE APPLICATIONS
NOTE:
1. DIMENSIONS IN INCH/(MILLIMETER)
2. DRAWING NOT TO SCALE
1117fd
13
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
PACKAGE DESCRIPTION
ST Package
3-Lead Plastic SOT-223
(Reference LTC DWG # 05-08-1630)
.248 – .264
(6.30 – 6.71)
.129 MAX
.114 – .124
(2.90 – 3.15)
.059 MAX
.264 – .287
(6.70 – 7.30)
.248 BSC
.130 – .146
(3.30 – 3.71)
.039 MAX
.059 MAX
.181 MAX
.033 – .041
(0.84 – 1.04)
.0905
(2.30)
BSC
RECOMMENDED SOLDER PAD LAYOUT
10° – 16°
.010 – .014
(0.25 – 0.36)
10°
MAX
.071
(1.80)
MAX
.090
BSC
10° – 16°
.024 – .033
(0.60 – 0.84)
.181
(4.60)
BSC
.012
(0.31)
MIN
.0008 – .0040
(0.0203 – 0.1016)
ST3 (SOT-233) 0502
1117fd
14
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
REVISION HISTORY
(Revision history begins at Rev D)
REV
DATE
DESCRIPTION
PAGE NUMBER
D
4/10
Updated DD-Pak part markings in Order Information section and revised all other sections.
1 to 16
1117fd
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
15
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
TYPICAL APPLICATION
High Efficiency Regulator
LT1117
1mH
28V INPUT
IN
+
MR1122
10k
ADJ
10,000μF
OUTPUT
OUT
240Ω
470Ω
28V
1k
1N914
2k
OUTPUT
ADJUST
+
100μF
1M
4N28
10k
+
LT1011
10k
–
28V
1N914
1117 TA15
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1118
Low IQ, Low Dropout, 800mA, Source
and Sink Regulators
Sources and Sinks Current, 600mA Quiescent Current, Dropout Voltage: 1V, SOIC-8 and
SOT-223 Packages
LT1129
700mA Micropower Low Dropout
Regulator
50μA Quiescent Current
LT1763
500mA, Low Noise LDO
300mV Dropout Voltage, Low Noise: 20μVRMS, VIN = 1.8V to 20V, SO-8 Package
LT1764, LT1764A
3A, Fast Transient Response, Low Noise
LDO
340mV Dropout Voltage, Low Noise: 40μVRMS, VIN = 2.7V to 20V, TO-220 and DD
Packages “A” version stable also with ceramic caps
LT1963, LT1763A
1.5A Low Noise, Fast Transient Response 340mV Dropout Voltage, Low Noise: 40μVRMS, VIN = 2.5V to 20V, “A” version stable
LDO
with ceramic caps, TO-220, DD, SOT-223 and SO-8 Packages
LT1965
1.1A, Low Noise, Low Dropout Linear
Regulator
290mV Dropout Voltage, Low Noise: 40μVRMS, VIN: 1.8V to 20V, VOUT: 1.2V to 19.5V,
stable with ceramic caps, TO-220, DDPak, MSOP and 3 × 3 DFN Packages
LT3021
500mA, Low Voltage, VLDO Linear
Regulator
VIN: 0.9V to 10V, Dropout Voltage: 160mV Typical, Adjustable Output (VREF = VOUT(MIN)
= 200mV), Fixed Output Voltages: 1.2V, 1.5V, 1.8V, Stable with Low ESR, Ceramic
Output Capacitors 16-Pin DFN (5mm × 5mm) and 8-Lead SO Packages
LT3080, LT3080-1
1.1A, Parallelable, Low Noise, Low
Dropout Linear Regulator
300mV Dropout Voltage (2-supply operation), Low Noise: 40μVRMS, VIN: 1.2V to 36V,
VOUT: 0V to 35.7V, current-based reference with 1-resistor VOUT set; directly parallelable
(no op amp required), stable with ceramic caps, TO-220, SOT-223, MS8E and 3 × 3
DFN-8 Packages; “-1” version has integrated internal ballast resistor
LT3085
500mA, Parallelable, Low Noise, Low
Dropout Linear Regulator
275mV Dropout Voltage (2-supply operation), Low Noise: 40μVRMS, VIN: 1.2V to 36V,
VOUT: 0V to 35.7V, current-based reference with 1-resistor VOUT set; directly parallelable
(no op amp required), stable with ceramic caps, MS8E and 2 × 3 DFN-6 packages
LTC3025-1, LTC3025-2, 500mA Micropower VLDO Linear
LTC3025-3, LTC3025-4 Regulator in 2 × 2 DFN
VIN = 0.9V to 5.5V, Dropout Voltage: 75mV, Low Noise 80μVRMS, Low IQ: 54μA, Fixed
Output: 1.2V (LTC3025-2), 1.5V (LTC3025-3), 1.8V (LTC3025-4); Adjustable Output
Range: 0.4V to 3.6V (LTC3025-1), 2mm × 2mm 6-Lead DFN Package
LTC3026
VIN: 1.14V to 3.5V (Boost Enabled), 1.14V to 5.5V (with External 5V), VDO = 0.1V, IQ =
950μA, Stable with 10μF Ceramic Capacitors, 10-Lead MSOP-E and DFN-10 Packages
1.5A, Low Input Voltage VLDO Linear
Regulator
1117fd
16 Linear Technology Corporation
LT 0410 REV D• PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com
© LINEAR TECHNOLOGY CORPORATION 1993
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