LINER LT1117IST-2.85 800ma low dropout positive regulators adjustable and fixed 2.85v, 3.3v, 5v Datasheet

LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
800mA Low Dropout
Positive Regulators
Adjustable and Fixed 2.85V,
3.3V, 5V
DESCRIPTIO
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FEATURES
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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
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APPLICATIO S
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Active SCSI Terminators
High Efficiency Linear Regulators
Post Regulators for Switching Supplies
Battery Chargers
5V to 3.3V Linear Regulators
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.
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.
, LTC and LT are registered trademarks of Linear Technology Corporation.
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TYPICAL APPLICATIO
Dropout Voltage (VIN – VOUT)
1.4
Active Terminator for SCSI-2 Bus
–40°C ≤ TJ < 0°C
110Ω
110Ω
LT1117-2.85
IN
4.75V TO
5.25V
GND
+
10µF
110Ω
OUT
+
22µF
110Ω
18 TO 27
LINES
DROPOUT VOLTAGE (V)
1.2
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
LT1117 • TA01
0
0
100 200 300 400 500 600 700 800
OUTPUT CURRENT (mA)
LT1117 • TPC01
1
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
W W
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ABSOLUTE
RATI GS
(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)
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PACKAGE/ORDER I FOR ATIO
FRONT VIEW
3
TAB IS
VOUT
2
1
IN
OUT
ADJ/GND
ST PACKAGE
3-LEAD PLASTIC SOT-223
TJ MAX = 125°C,θJC = 15°C/W
ORDER PART
NUMBER
LT1117CST
LT1117CST-2.85
LT1117CST-3.3
LT1117CST-5
LT1117IST
LT1117IST-2.85
LT1117IST-3.3
LT1117IST-5
ST PART MARKING
1117
1117I
11172 1117I2
11173 1117I3
11175 1117I5
ORDER PART
NUMBER
LT1117CM
LT1117CM-2.85
LT1117CM-3.3
LT1117CM-5
FRONT VIEW
TAB IS
VOUT
3
IN
2
OUT
1
ADJ/GND
M PACKAGE
3-LEAD PLASTIC DD
DD PART MARKING
TJ MAX = 125°C,θJC = 10°C/W
1117
11172
11173
11175
Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TJ = 25°C.
PARAMETER
Reference Voltage
Output Voltage
CONDITIONS
LT1117
LT1117-2.85
LT1117-3.3
LT1117-5
Line Regulation
2
LT1117
LT1117-2.85
LT1117-3.3
LT1117-5
MIN
TYP
MAX
UNITS
IOUT = 10mA, (VIN – VOUT) = 2V, TJ = 25°C
10 ≤ IOUT ≤ 800mA, 1.4V ≤ (VIN – VOUT) ≤ 10V
●
1.238
1.225
1.250 1.262
1.250 1.270
V
V
IOUT = 10mA, VIN = 4.85V, TJ = 25°C
0 ≤ IOUT ≤ 800mA, 4.25V ≤ VIN ≤ 10V
0 ≤ IOUT ≤ 500mA, VIN = 3.95V
●
●
2.820
2.790
2.790
2.850 2.880
2.850 2.910
2.850 2.910
V
V
V
IOUT = 10mA, VIN = 5V, TJ = 25°C
0 ≤ IOUT ≤ 800mA, 4.75V ≤ VIN ≤ 10V
●
3.267
3.235
3.300 3.333
3.300 3.365
V
V
IOUT = 10mA, VIN = 7V, TJ = 25°C
0 ≤ IOUT ≤ 800mA, 6.50V ≤ VIN ≤ 12V
●
4.950
4.900
5.000 5.050
5.000 5.100
V
V
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)
●
●
●
●
0.035
1
1
1
0.2
6
6
10
%
mV
mV
mV
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TJ = 25°C.
PARAMETER
Load Regulation
CONDITIONS
MIN
TYP
MAX
UNITS
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
(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)
LT1117
LT1117-2.85
LT1117-3.3
LT1117-5
Dropout Voltage
Current Limit
●
●
●
●
(VIN – VOUT) = 5V, TJ = 25°C,
800
Minimum Load Current
LT1117
(VIN – VOUT) = 15V (Note 4)
●
1.7
5
mA
Quiescent Current
LT1117-2.85
LT1117-3.3
LT1117-5
VIN ≤ 10V
VIN ≤ 15V
VIN ≤ 15V
●
●
●
5
5
5
10
10
10
mA
mA
mA
0.01
0.1
%/W
Thermal Regulation
TA = 25°C, 30ms Pulse
Ripple Rejection
fRIPPLE = 120Hz, (VIN – VOUT) = 3V, VRIPPLE = 1VP-P
●
Adjust Pin Current
10mA ≤ IOUT ≤ 800mA, 1.4V ≤ (VIN – VOUT) ≤ 10V
Adjust Pin Current Change
60
75
dB
●
55
120
µA
●
0.2
5
µA
Temperature Stability
0.5
Long Term Stability
TA = 125°C, 1000Hrs
RMS Output Noise
(% of VOUT), 10Hz ≤ f ≤ 10kHz
Thermal Resistance
(Junction-to-Case, at Tab)
Note 1: Absolute Maximum Ratings are those values beyond which the life
to the device may be imparied.
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.
%
0.3
%
0.003
%
°C/W
15
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.
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TYPICAL PERFOR A CE 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
5
10
15
INPUT/OUTPUT DIFFERENTIAL (V)
20
LT1117 • TPC02
0
5
10
INPUT/OUTPUT DIFFERENTIAL (V)
15
LT1117 • TPC03
∆ ILOAD = 800mA
0.05
0
– 0.05
– 0.10
– 0.15
– 0.20
–50
–25
0
25
50
75
TEMPERATURE (°C)
100
125
LT1117 • TPC04
3
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
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TYPICAL PERFOR A CE CHARACTERISTICS
LT1117 Ripple Rejection
LT1117 Ripple Rejection vs Current
100
60
50
40
(VIN – VOUT) ≥ VDROPOUT
30
10
0
100
fRIPPLE = 120Hz
VRIPPLE ≤ 3VP-P
70
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
1.0
0
–1.0
10
–2.0
–50 –25
0
1k
10k
FREQUENCY (Hz)
0
100k
0.2
0.4
0.6
OUTPUT CURRENT (A)
LT1117 • TPC05
0.8
0.3
OUPUT VOLTAGE
DEVIATION (V)
100
80
70
60
LT1117-5
Load Transient Response
0.3
CIN = 10µF
COUT = 10µF TANTALUM
VIN = 4.25V
PRELOAD = 0.1A
0.2
0.1
0
CIN = 10µF
0.2 COUT = 10µF TANTALUM
VIN = 6.5V
0.1 PRELOAD = 0.1A
0
–0.1
40
–0.2
–0.2
20
10
0
–50 –25
0
25 50 75 100 125 150
TEMPERATURE (°C)
0.5
0
–0.5
0
10 20 30 40 50 60 70 80 90 100
TIME (µs)
LT1117 • TPC08
–0.5
0
10 20 30 40 50 60 70 80 90 100
TIME (µs)
LT1117 • TPC10
60
OUPUT 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)
LT1117 • TPC11
CIN = 1µF
COUT = 10µF TANTALUM
IOUT = 0.1A
40
–20
INPUT VOLTAGE
(V)
OUPUT VOLTAGE
DEVIATION (mV)
INPUT VOLTAGE
(V)
0
LT1117-5
Line Transient Response
60
4
0.5
LT1117 • TPC09
LT1117-2.8
Line Transient Response
0
LOAD CURRENT
(A)
–0.1
LOAD CURRENT
(A)
50
30
25 50 75 100 125 150
TEMPERATURE (°C)
LT1117 • TPC07
LT1117-2.85
Load Transient Response
90
0
LT1117 • TPC06
Adjust Pin Current
AJUST PIN CURRENT (µA)
OUTPUT VOLTAGE CHANGE (%)
70
RIPPLE REJECTION (dB)
(VIN – VOUT) ≥ 3V
OUPUT VOLTAGE
DEVIATION (V)
80
RIPPLE REJECTION (dB)
VOUT = 5V
90 CADJ = 25µF
COUT = 25µF
80
VRIPPLE ≤
0.5VP-P
VRIPPLE ≤ 3VP-P
90
20
Temperature Stability
2.0
100
7.50
6.50
5.50
0
20 40 60 80 100 120 140 160 180 200
TIME (µs)
LT1117 • TPC12
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
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BLOCK DIAGRA
IN
+
–
THERMAL
LIMIT
ADJ
GND
OUT
FOR FIXED VOLTAGE DEVICE
LT1117 • BD01
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APPLICATIO HI TS
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.
5
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
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APPLICATIO HI TS
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
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.
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:
LT1117 • TA02
RP ×
Figure 1
R2 + R1
,RP = Parasitic Line Resistance
R1
Output Voltage
RP
PARASITIC
LINE RESISTANCE
LT1117
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
VIN
IN
OUT
ADJ
R1
CONNECT
R1 TO CASE
RL
R2
LT1117
LT1117 • TA04
VIN
+
IN
ADJ
IADJ
50µA
VOUT
OUT
( )
VREF
R2
VOUT = VREF 1 + — + IADJ R2
R1
R1
Figure 3. Connections for Best Load Regulation
R2
LT1117 • TA03
Figure 2. Basic Adjustable Regulator
6
CONNECT
R2 TO LOAD
For fixed voltage devices the top of R1 is internally Kelvin
connected, and the ground pin can be used for negative
side sensing.
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
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APPLICATIO HI TS
Thermal Considerations
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.
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
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.
* Tab of device attached to topside copper
7
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
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TYPICAL APPLICATIO S
1.2V to 10V Adjustable Regulator
5V Regulator with Shutdown
LT1117
LT1117
VIN
IN
VOUT†
OUT
R1
121Ω
ADJ
+
IN
R2
1k
121Ω
1%
10µF
C2
100µF
5V
OUT
ADJ
+
+
C1*
10µF
VIN
+
100µF
1k
2N3904
TTL
1k
365Ω
1%
* NEEDED IF DEVICE IS FAR FROM FILTER CAPACITORS
R2
†V
—
OUT = 1.25V 1 + R1
( )
LT1117 • TA06
LT1117 • TA05
Remote Sensing
RP
(MAX. DROP 300mV)
LT1117
VIN
IN
OUTPUT
5V
OUT
ADJ
VIN
+
100µF
25Ω
+
7
6
–
LM301A
1
10µF
121Ω
2
+
8
4
5µF
+
365Ω
RL
3 1k
100pF
RETURN
25Ω
RETURN
LT1117 • TA07
Adjusting Output Voltage of Fixed Regulators
Regulator with Reference
LT1117-5
LT1117-5
VIN > 12V
IN
+
OUT
GND
10µF
+
5V TO 10V
100µF
10µF
+
IN
OUT
GND
+
10V
100µF
5VOUT
+
10µF*
VIN > 11.5V
LT1029
1k
LT1117 • TA06
* OPTIONAL IMPROVES RIPPLE REJECTION
LT1117 • TA05
8
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
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TYPICAL APPLICATIO S
Battery Charger
Battery Backed Up Regulated Supply
LT1117
VIN
LT1117-5
IF
OUT
IN
VOUT
RS
1.25V
VIN
+
50Ω
( )
( )
R2
VOUT – 1.25V 1 + —
R1
SELECT FOR
CHARGE RATE
R2
–RS 1 + —
R1
∆IF
=
∆VOUT
1
( )
R2
–RS 1 + —
R1
6.5V
10µF
OUT
GND
10µF
+
100µF
LT1117 • TA07
LT1117 • TA08
Automatic Light Control
LT1117
LT1117
+
LT1117-5
IN
+
Improving Ripple Rejection
IN
GND
R1
IF =
5.2V LINE
5.0V BATTERY
OUT
10µF
ADJ
VIN
IN
OUT
ADJ
R2
365Ω
* C1 IMPROVES RIPPLE
1%
REJECTION. XC SHOULD BE
≈ R1 AT RIPPLE FREQUENCY
VIN ≥ 16.5V
R1
121Ω
1%
IN
+
10µF
+
OUT
ADJ
1.2k
100µF
150µF
C1
10µF
LT1117 • TA10
LT1117 • TA09
High Efficiency Dual Supply
FEEDBACK PATH
MUR410
3.3V OUTPUT (TYPICAL)
+
470µF
LT1117-5
MUR410
IN
+5V
0.5A
OUT
+
GND
+
470µF
10µF
1N4002
10µF
1N4002
+VIN
LT1117-5
MUR410
SWITCHING
REGULATOR
IN
OUT
GND
+
470µF
+
–5V
0.5A
LT1117 • TA11
9
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
U
TYPICAL APPLICATIO S
High Efficiency Dual Linear Supply
L1
285µH
MBR360
(HEAT SINK)
2N6667 Q1
(DARLINGTON)
10k
1k
LT1117-5
IN
+
1000µF
GND
2.4k
510k
LT1004-2.5
30k
+
MDA201
V+
+
–
5V
0.5A
OUT
+
20k*
+
100µF
D11
1N4002
100µF
D2
1N4002
30.1k*
1/2
LT1018
4700µF
–
130VAC
TO 90VAC
L1
285µH
STANCOR
P-8685
MBR360
(HEAT SINK)
2N6667
(DARLINGTON)
10k
1k
LT1117-5
IN
+
1000µF
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
LT1117 • TA12
Low Dropout Negative Supply
LT1117-5
VIN
IN
+
10µF
FLOATING INPUT
10
OUT
GND
+
100µF
VOUT = –5V
LT1117 • TA13
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
W U
SOLDERI G
ETHODS
The SOT-223 is manufactured with gull wing leadform for
surface mount applications. The leads and heat sink are
solder plated and allow easy soldering using nonactive or
mildly active fluxes. The package is constructed with three
leads exiting one side of the package and one heat sink
exiting the other side, and the die attached to the heat sink
internally.
these methods can easily damage the part with excessive
thermal gradients across the package.
Care must be exercised during surface mount to minimize
large (> 30°C per second) thermal shock to the package.
The recommended methods of soldering SOT-223 are:
vapor phase reflow and infrared reflow with preheat of
component to within 65°C of the solder temperature. Hand
soldering and wave soldering are not recommended since
U
PACKAGE DESCRIPTIO
LT1117 • TA15
Dimensions in inches (millimeters) unless otherwise noted.
M Package
3-Lead Plastic DD Pak
(LTC DWG # 05-08-1460)
0.256
(6.502)
0.060
(1.524)
0.060
(1.524)
TYP
0.390 – 0.415
(9.906 – 10.541)
0.165 – 0.180
(4.191 – 4.572)
0.045 – 0.055
(1.143 – 1.397)
15° TYP
0.060
(1.524)
0.183
(4.648)
0.059
(1.499)
TYP
0.330 – 0.370
(8.382 – 9.398)
(
+0.203
0.102 –0.102
BOTTOM VIEW OF DD PAK
HATCHED AREA IS SOLDER PLATED
COPPER HEAT SINK
)
0.095 – 0.115
(2.413 – 2.921)
0.075
(1.905)
0.300
(7.620)
+0.008
0.004 –0.004
(
+0.012
0.143 – 0.020
+0.305
3.632 –0.508
)
0.090 – 0.110
(2.286 – 2.794)
0.050 ± 0.012
(1.270 ± 0.305)
0.013 – 0.023
(0.330 – 0.584)
0.050
(1.270)
BSC
M (DD3) 1098
ST Package
3-Lead Plastic SOT-223
(LTC DWG # 05-08-1630)
0.248 – 0.264
(6.30 – 6.71)
0.114 – 0.124
(2.90 – 3.15)
10° – 16°
0.264 – 0.287
(6.70 – 7.30)
0.130 – 0.146
(3.30 – 3.71)
0.010 – 0.014
(0.25 – 0.36)
10°
MAX
0.071
(1.80)
MAX
10° – 16°
0.024 – 0.033
(0.60 – 0.84)
0.181
(4.60)
NOM
0.0905
(2.30)
NOM
0.012
(0.31)
MIN
0.0008 – 0.0040
(0.0203 – 0.1016)
ST3 (SOT-233) 1298
0.033 – 0.041
(0.84 – 1.04)
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.
11
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
U
TYPICAL APPLICATIO
High Efficiency Regulator
LT1117
1mH
28V INPUT
IN
+
10,000µF
MR1122
10k
OUTPUT
OUT
ADJ
240Ω
470Ω
28V
1k
+
100µF
2k
OUTPUT
ADJUST
1N914
1M
4N28
10k
+
LT1011
10k
–
28V
1N914
LT1117 • TA14
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1120
125mA Low Dropout Regulator with 20µA IQ
Includes 2.5V Reference and Comparator
LT1121
150mA Micropower Low Dropout Regulator
30µA IQ, SOT-223 Package
LT1129
700mA Micropower Low Dropout Regulator
50µA Quiescent Current
LT1175
500mA Negative Low Dropout Micropower Regulator
45µA IQ, 0.26V Dropout Voltage, SOT-223 Package
LT1374
4.5A, 500kHz Step-Down Converter
4.5A, 0.07Ω Internal Switch, SO-8 Package
LT1521
300mA Low Dropout Micropower Regulator with Shutdown
15µA IQ, Reverse Battery Protection
TM
LT1573
UltraFast Transient Response Low Dropout Regulator
Drives External PNP
LT1575
UltraFast Transient Response Low Dropout Regulator
Drives External N-Channel MOSFET
LT1735
Synchronous Step-Down Converter
High Efficiency, OPTI-LOOPTM Compensation
LT1761 Series
100mA, Low Noise, Low Dropout Micropower Regulators in SOT-23
20µA Quiescent Current, 20µVRMS Noise, SOT-23 Package
LT1762 Series
150mA, Low Noise, LDO Micropower Regulators
25µA Quiescent Current, 20µVRMS Noise, MSOP Package
LT1763 Series
500mA, Low Noise, LDO Micropower Regulators
30µA Quiescent Current, 20µVRMS Noise, SO-8 Package
LT1764 Series
3A, Low Noise, Fast Transient Response LDO
40µVRMS Noise, DD and TO-220 Packages
LT1962
300mA, Low Noise, LDO Micropower Regulator
20µVRMS Noise, MSOP Package
LT1963
1.5A, Low Noise, Fast Transient Response LDO
40µVRMS Noise, SOT-223 Package
UltraFast and OPT-LOOP are trademarks of Linear Technology Corporation.
12
Linear Technology Corporation
sn1117 1117fcs LT/TP 0500 2K REV C • PRINTED IN
1630 McCarthy Blvd., Milpitas, CA 95035-7417
USA
(408)432-1900 FAX: (408) 434-0507 www.linear-tech.com
 LINEAR TECHNOLOGY CORPORATION 1993
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