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Электронный компонент: LT1117CM-3.3

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1
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
800mA Low Dropout
Positive Regulators
Adjustable and Fixed 2.85V,
3.3V, 5V
Active Terminator for SCSI-2 Bus
Dropout Voltage (V
IN
V
OUT
)
U
A
O
PPLICATI
TYPICAL
D
U
ESCRIPTIO
S
FEATURE
s
Space Saving SOT-223 Surface Mount Package
s
Three-Terminal Adjustable or Fixed 2.85V, 3.3V, 5V
s
Output Current of 800mA
s
Operates Down to 1V Dropout
s
Guaranteed Dropout Voltage at Multiple Current Levels
s
0.2% Line Regulation Max
s
0.4% Load Regulation Max
The LT1117 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 10
F 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.
U
S
A
O
PPLICATI
s
Active SCSI Terminators
s
High Efficiency Linear Regulators
s
Post Regulators for Switching Supplies
s
Battery Chargers
s
5V to 3.3V Linear Regulators
18 TO 27
LINES
LT1117 TA01
+
+
10
F
110
110
110
110
4.75V TO
5.25V
22
F
LT1117-2.85
IN
GND
OUT
OUTPUT CURRENT (mA)
0
0
DROPOUT VOLTAGE (V)
0.2
0.4
0.6
0.8
1.0
1.4
100
400
600
800
LT1117 TPC01
1.2
200 300
500
700
T
J
= 25
C
T
J
= 125
C
INDICATES GUARANTEED TEST POINT
2
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
A
U
G
W
A
W
U
W
A
R
BSOLUTE
XI
TI
S
Input Voltage
Operating Voltage
LT1117, LT1117-3.3, LT1117-5 ...................... 15V
LT1117-2.85 ................................................... 10V
Surge Voltage
LT1117, LT1117-3.3, LT1117-5 ...................... 20V
W
U
U
PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
LT1117CST
LT1117CST-2.85
LT1117CST-3.3
LT1117CST-5
PART MARKING
ORDER PART
NUMBER
LT1117CM
LT1117CM-2.85
LT1117CM-3.3
LT1117CM-5
PART MARKING
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Reference Voltage
LT1117
I
OUT
= 10mA, (V
IN
V
OUT
) = 2V, T
J
= 25
C
1.238
1.250
1.262
V
10
I
OUT
800mA, 1.4V
(V
IN
- V
OUT
)
10V
q
1.225
1.250
1.270
V
Output Voltage
LT1117-2.85
I
OUT
= 10mA, V
IN
= 4.85V, T
J
= 25
C
2.820
2.850
2.880
V
0
I
OUT
800mA, 4.25V
V
IN
10V
q
2.790
2.850
2.910
V
0
I
OUT
500mA, V
IN
= 3.95V
q
2.790
2.850
2.910
V
LT1117-3.3
I
OUT
= 10mA, V
IN
= 5V, T
J
= 25
C
3.267
3.300
3.333
V
0
I
OUT
800mA, 4.75V
V
IN
10V
q
3.235
3.300
3.365
V
LT1117-5
I
OUT
= 10mA, V
IN
= 7V, T
J
= 25
C
4.950
5.000
5.050
V
0
I
OUT
800mA, 6.50V
V
IN
12V
q
4.900
5.000
5.100
V
Line Regulation
LT1117
I
OUT
= 10mA, 1.5V
V
IN
V
OUT
15V (Note 1)
q
0.035
0.2
%
LT1117-2.85
I
OUT
= 0mA, 4.25V
V
IN
10V (Note 1)
q
1
6
mV
LT1117-3.3
I
OUT
= 0mA, 4.75V
V
IN
15V (Note 1)
q
1
6
mV
LT1117-5
I
OUT
= 0mA, 6.5V
V
IN
15V (Note 1)
q
1
10
mV
Load Regulation
LT1117
(V
IN
V
OUT
) = 3V, 10mA
I
OUT
800mA (Note 1)
q
0.1
0.4
%
LT1117-2.85
V
IN
= 4.25V, 0
I
OUT
800mA (Note 1)
q
1
10
mV
LT1117-3.3
V
IN
= 4.75V, 0
I
OUT
800mA (Note 1)
q
1
10
mV
LT1117-5
V
IN
= 6.5V, 0
I
OUT
800mA (Note 1)
q
1
15
mV
Dropout Voltage
I
OUT
= 100mA (Note 2)
q
1.00
1.10
V
I
OUT
= 500mA (Note 2)
q
1.05
1.15
V
I
OUT
= 800mA (Note 2)
q
1.10
1.20
V
Current Limit
(V
IN
V
OUT
) = 5V, T
J
= 25
C,
800
950
1200
mA
Minimum Load Current
LT1117
(V
IN
V
OUT
) = 15V (Note 3)
q
1.7
5
mA
ELECTRICAL C
C
HARA TERISTICS
Operating JunctionTemperature Range ..... 0
C to 125
C
Storage Temperature Range ................. 65
C to 150
C
Lead Temperature ................... (See Soldering Methods)
T
J MAX
= 125
C,
JC
= 15
C/W
FRONT VIEW
TAB IS
V
OUT
IN
OUT
ADJ/GND
ST PACKAGE
3-LEAD PLASTIC SOT-223
3
2
1
M PACKAGE
3-LEAD PLASTIC DD
FRONT VIEW
3
2
1
IN
OUT
ADJ/GND
TAB IS
V
OUT
T
J MAX
= 125
C,
JC
= 10
C/W
11173
11175
1117
11172
11173
11175
1117
11172
Consult factory for Industrial and Military grade parts.
3
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Quiescent Current
LT1117-2.85
V
IN
10V
q
5
10
mA
LT1117-3.3
V
IN
15V
q
5
10
mA
LT1117-5
V
IN
15V
q
5
10
mA
Thermal Regulation
T
A
= 25
C, 30ms Pulse
0.01
0.1
%/W
Ripple Rejection
f
RIPPLE
= 120Hz, (V
IN
V
OUT
) = 3V,
V
RIPPLE
= 1Vp-p
q
60
75
dB
Adjust Pin Current
q
55
120
A
Adjust Pin Current Change
10mA
I
OUT
800mA, 1.4V
(V
IN
V
OUT
)
10V
q
0.2
5
A
Temperature Stability
0.5
%
Long Term Stability
T
A
= 125
C, 1000Hrs
0.3
%
RMS Output Noise
(% of V
OUT
), 10Hz
f
10kHz
0.003
%
Thermal Resistance
(Junction-to-Case, at Tab)
15
C/W
ELECTRICAL C
C
HARA TERISTICS
The
q
denotes specifications which apply over the full operating
temperature range.
Note 1: 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.
Note 2: 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 3: Minimum load current is defined as the minimum output current
required to maintain regulation.
C
C
HARA TERISTICS
U
W
A
TYPICAL PERFOR
CE
Minimum Operating Current
(Adjustable Device)
Short-Circuit Current
Load Regulation
INPUT/OUTPUT DIFFERENTIAL (V)
0
0
MINIMUM OPERATING CURRENT (mA)
1
3
4
10
15
20
LT1117 TPC02
5
T
J
= 25
C
T
J
= 125
C
T
J
= 55
C
2
INPUT/OUTPUT DIFFERENTIAL (V)
0
0
SHORT CIRCUIT CURRENT (A) 0.25
0.50
0.75
1.25
10
15
LT1117 TPC03
5
1.00
T
J
= 25
C
T
J
= 125
C
TEMPERATURE (
C)
50
0.20
OUTPUT VOLTAGE DEVIATION (%) 0.15
0.10
0.05
0.10
50
75
125
LT1117 TPC04
0
0.05
0
25
25
100
I
LOAD
= 800mA
4
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
C
C
HARA TERISTICS
U
W
A
TYPICAL PERFOR
CE
LT1117-5
Line Transient Response
LT1117-2.8
Line Transient Response
LT1117 Ripple Rejection

LT1117 Ripple Rejection vs Current
Temperature Stability
LT1117-2.85
LT1117-5
Adjust Pin Current
Load Transient Response
Load Transient Response
TEMPERATURE (
C)
50
2.0
OUTPUT VOLTAGE CHANGE (%)
1.0
0
2.0
0
50
100
150
LT1117 TPC07
1.0
25
25
75
125
TEMPERATURE (
C)
50
0
AJUST PIN CURRENT (
A)
20
50
100
0
50
100
150
LT1117 TPC08
80
25
25
75
125
10
30
40
60
70
90
FREQUENCY (Hz)
20
RIPPLE REJECTION (dB)
40
60
80
100
10
1k
10k
100k
LT1117 TPC05
0
100
90
70
50
30
10
C
ADJ
= 200
F AT f < 60Hz
C
ADJ
= 25
F AT f > 60Hz
I
OUT
= 0.5A
(V
IN
V
OUT)
V
DROPOUT
V
RIPPLE
3V
P-P
V
RIPPLE
0.5V
P-P
(V
IN
V
OUT)
3V
TIME (
s)
0
0.5
LOAD CURRENT
(A)
0.3
20
50
70
100
LT1117 TPC09
0.1
10
30
60
80
0
0.5
0.2
0
0.2
0.1
40
90
OUPUT VOLTAGE
DEVIATION (V)
C
IN
= 10
F
C
OUT
= 10
F TANTALUM
V
IN
= 4.25V
PRELOAD = 0.1A
TIME (
s)
0
0.5
LOAD CURRENT
(A)
0.3
20
50
70
100
LT1117 TPC10
0.1
10
30
60
80
0
0.5
0.2
0
0.2
0.1
40
90
OUPUT VOLTAGE
DEVIATION (V)
C
IN
= 10
F
C
OUT
= 10
F TANTALUM
V
IN
= 6.5V
PRELOAD = 0.1A
TIME (
s)
0
3.25
INPUT VOLTAGE
(V)
60
40
100
140
200
LT1117 TPC11
20
20
60
120
160
4.25
5.25
40
0
40
20
80
180
OUPUT VOLTAGE
DEVIATION (mV)
C
IN
= 1
F
C
OUT
= 10
F TANTALUM
I
OUT
= 0.1A
TIME (
s)
0
5.50
INPUT VOLTAGE
(V)
60
40
100
140
200
LT1117 TPC12
20
20
60
120
160
6.50
7.50
40
0
40
20
80
180
OUPUT VOLTAGE
DEVIATION (mV)
C
IN
= 1
F
C
OUT
= 10
F TANTALUM
I
OUT
= 0.1A
OUTPUT CURRENT (A)
0
0
RIPPLE REJECTION (dB)
20
30
50
80
100
0.2
0.4
0.6
0.8
LT1117 TPC06
10
40
60
70
90
V
OUT
= 5V
C
ADJ
= 25
F
C
OUT
= 25
F
V
RIPPLE
3V
P-P
f
RIPPLE
=
120Hz
f
RIPPLE
=
20kHz
V
RIPPLE
0.5V
P-P
5
LT1117/LT1117-2.85
LT1117-3.3/LT1117-5
W
I
D AGRA
BLOCK
U
A
O
PPLICATI
HI
U
TS
The LT1117 family of three-terminal regulators are easy to
use. They are protected against short circuit and thermal
overloads. Thermal protection circuitry will shutdown the
regulator should the junction temperature exceed 165
C
at the sense point. These regulators are pin compatible
with older three-terminal adjustable regulators, offer
lower dropout voltage and more precise reference toler-
ance. Reference stability over temperature is improved
over older types of regulators.
Stability
The LT1117 family of regulators requires an output ca-
pacitor as part of the device frequency compensation. A
minimum of 10
F of tantalum or 50
F of aluminum
electrolytic is required. The ESR of the output capacitor
should be less than 0.5
. Surface mount tantalum capaci-
tors, 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 22
F tantalum or 150
F aluminum
electrolytic when the adjust pin is bypassed.
Normally, capacitor values on the order of 100
F are used
in the output of many regulators to ensure good load
transient response with large load current changes. Out-
put 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 stress-
ing 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
LT1117 BD01
+
THERMAL
LIMIT
OUT
IN
ADJ
GND
FOR FIXED VOLTAGE DEVICE