Storage Temperature Range................... –65°C to 150°C
Operating Junction Temperature Range (Note 2)
Commercial............................................ 0°C to 125°C
Industrial ......................................... –40°C to 125°C
Lead Temperature (Soldering, 10 sec) .................. 300°C
*For applications requiring input voltage ratings greater than 20V, contact
the factory.
PIN CONFIGURATION
TOP VIEW
TOP VIEW
OUT
SENSE/ADJ*
NC
GND
1
2
3
4
8
7
6
5
IN
NC
NC
SHDN
OUT 1
SENSE/ADJ* 2
GND 3
NC 4
8
7
6
5
IN
GND
GND
SHDN
TAB IS
GND
FRONT VIEW
3
2
1
OUT
GND
IN
MS8 PACKAGE
8-LEAD PLASTIC MSOP
*PIN 2 = SENSE FOR LT1521-3/
LT1521-3.3/LT1521-5
PIN 2 = ADJ FOR LT1521
T
JMAX
= 125°C,
θ
JA
= 125°C/W
S8 PACKAGE
8-LEAD PLASTIC SO
*PIN 2 = SENSE FOR LT1521-3/LT1521-3.3/LT1521-5
= ADJ FOR LT1521
T
JMAX
= 125°C,
θ
JA
= 70°C/W
SEE THE APPLICATIONS INFORMATION SECTION
ST PACKAGE
3-LEAD PLASTIC SOT-223
T
JMAX
= 125°C,
θ
JA
= 50°C/W
SEE THE APPLICATIONS INFORMATION SECTION
ORDER INFORMATION
LEAD FREE FINISH
LT1521CMS8#PBF
LT1521CMS8-3#PBF
LT1521CMS8-3.3#PBF
LT1521CMS8-5#PBF
LT1521CS8#PBF
LT1521CS8-3#PBF
LT1521CS8-3.3#PBF
LT1521CS8-5#PBF
LT1521IS8#PBF
LT1521IS8-3#PBF
LT1521IS8-3.3#PBF
LT1521IS8-5#PBF
TAPE AND REEL
LT1521CMS8#TRPBF
LT1521CMS8-3#TRPBF
LT1521CMS8-5#TRPBF
LT1521CS8#TRPBF
LT1521CS8-3#TRPBF
LT1521CS8-3.3#TRPBF
LT1521CS8-5#TRPBF
LT1521IS8#TRPBF
LT1521IS8-3#TRPBF
LT1521IS8-3.3#TRPBF
LT1521IS8-5#TRPBF
PART MARKING*
LTEZ
LTFB
LTFA
1521
15213
152133
15215
1521I
1521I3
1521I33
1521I5
PACKAGE DESCRIPTION
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic SOIC
8-Lead Plastic SOIC
8-Lead Plastic SOIC
8-Lead Plastic SOIC
8-Lead Plastic SOIC
8-Lead Plastic SOIC
8-Lead Plastic SOIC
8-Lead Plastic SOIC
TEMPERATURE RANGE
0°C to 125°C
0°C to 125°C
0°C to 125°C
0°C to 125°C
0°C to 125°C
0°C to 125°C
0°C to 125°C
0°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
LT1521CMS8-3.3#TRPBF LTDU
2
Rev. C
For more information
www.analog.com
LT1521/LT1521-3
LT1521-3.3/LT1521-5
ORDER INFORMATION
LEAD FREE FINISH
LT1521CST-3#PBF
LT1521CST-3.3#PBF
LT1521CST-5#PBF
LT1521IST-3#PBF
LT1521IST-3.3#PBF
LT1521IST-5#PBF
TAPE AND REEL
LT1521CST-3#TRPBF
LT1521CST-3.3#TRPBF
LT1521CST-5#TRPBF
LT1521IST-3#TRPBF
LT1521IST-3.3#TRPBF
LT1521IST-5#TRPBF
PART MARKING*
15213
152133
15215
1521I3
1521I33
1521I5
PACKAGE DESCRIPTION
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
TEMPERATURE RANGE
0°C to 125°C
0°C to 125°C
0°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
Contact the factory for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
Tape and reel specifications.
Some packages are available in 500 unit reels through designated sales channels with #TRMPBF suffix.
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C.
PARAMETER
Regulated Output Voltage
(Note 4)
CONDITIONS
LT1521-3
LT1521-3.3
LT1521-5
LT1521 (Note 5)
Line Regulation
LT1521-3
LT1521-3.3
LT1521-5
LT1521 (Note 5)
Load Regulation
LT1521-3
LT1521-3.3
LT1521-5
LT1521 (Note 5)
LT1521-3
LT1521-3.3
LT1521-5
LT1521 (Note 5)
Dropout Voltage (Note 6)
V
IN
= 3.5V, I
OUT
= 1mA, T
J
= 25°C
4V < V
IN
< 20V, 1mA < I
OUT
< 300mA
V
IN
= 3.8V, I
OUT
= 1mA, T
J
= 25°C
4.3V < V
IN
< 20V, 1mA < I
OUT
< 300mA
V
IN
= 5.5V, I
OUT
= 1mA, T
J
= 25°C
6V < V
IN
< 20V, 1mA < I
OUT
< 300mA
V
IN
= 4.3V, I
OUT
= 1mA, T
J
= 25°C
4.8V < V
IN
< 20V, 1mA < I
OUT
< 300mA
∆V
IN
= 4.5 to 20V, I
OUT
= 1mA
∆V
IN
= 4.8 to 20V, I
OUT
= 1mA
∆V
IN
= 5.5 to 20V, I
OUT
= 1mA
∆V
IN
= 4.3 to 20V, I
OUT
= 1mA
∆I
LOAD
= 1mA to 300mA, T
J
≤ 25°C
∆I
LOAD
= 1mA to 300mA, T
J
≤ 25°C
∆I
LOAD
= 1mA to 300mA, T
J
≤ 25°C
∆I
LOAD
= 1mA to 300mA, T
J
≤ 25°C
∆I
LOAD
= 1mA to 300mA, T
J
> 25°C
∆I
LOAD
= 1mA to 300mA, T
J
> 25°C
∆I
LOAD
= 1mA to 300mA, T
J
> 25°C
∆I
LOAD
= 1mA to 300mA, T
J
> 25°C
l
l
l
l
l
l
l
l
l
ELECTRICAL CHARACTERISTICS
MIN
2.950
2.900
3.250
3.200
4.925
4.850
3.695
3.640
TYP
3.000
3.000
3.300
3.300
5.000
5.000
3.750
3.750
1.5
1.5
1.5
1.5
–20
–20
–25
–20
–20
–20
–25
–20
130
290
MAX
3.050
3.100
3.350
3.400
5.075
5.150
3.805
3.860
20
20
20
20
–30
–30
–45
–30
–55
–55
–75
–55
170
250
350
450
420
550
470
600
600
750
UNITS
V
V
V
V
V
V
V
V
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
I
LOAD
= 1mA, T
J
= 25°C
I
LOAD
= 1mA
I
LOAD
= 50mA, T
J
= 25°C
I
LOAD
= 50mA
I
LOAD
= 100mA, T
J
= 25°C
I
LOAD
= 100mA
I
LOAD
= 150mA, T
J
= 25°C
I
LOAD
= 150mA
I
LOAD
= 300mA, T
J
= 25°C
I
LOAD
= 300mA
l
350
l
400
l
500
l
For more information
www.analog.com
3
Rev. C
LT1521/LT1521-3
LT1521-3.3/LT1521-5
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C.
PARAMETER
Ground Pin Current (Note 7)
CONDITIONS
I
LOAD
= 0mA
I
LOAD
= 1mA
I
LOAD
= 10mA
I
LOAD
= 50mA
I
LOAD
= 100mA
I
LOAD
= 150mA
I
LOAD
= 300mA
Adjust Pin Bias Current (Notes 5, 8)
Shutdown Threshold
Shutdown Pin Current (Note 9)
Quiescent Current in Shutdown (Note 10)
Ripple Rejection
Current Limit
Input Reverse Leakage Current
Reverse Output Current (Note 11)
T
J
= 25°C
V
OUT
= Off to On
V
OUT
= On to Off
V
SHDN
= 0V
V
IN
= V
OUT
(NOMINAL) + 1V, V
SHDN
= 0V
V
IN
– V
OUT
= 1V(Avg), V
RIPPLE
= 0.5V
P–P
,
f
RIPPLE
= 120Hz, I
LOAD
= 150mA
V
IN
– V
OUT
= 7V, T
J
= 25°C
V
IN
= V
OUT
(NOMINAL) + 1.5V, ∆V
OUT
= –0.1V
V
IN
= –20V, V
OUT
= 0V
LT1521-3
LT1521-3.3
LT1521-5
LT1521 (Note 5)
V
OUT
= 3V, V
IN
< 3V, T
J
= 25°C
V
OUT
= 3.3V, V
IN
< 3.3V, T
J
= 25°C
V
OUT
= 5V, V
IN
< 5V, T
J
= 25°C
V
OUT
= 3.8V, V
IN
< 3.75V, T
J
= 25°C
l
l
l
l
l
l
l
l
l
l
l
l
l
ELECTRICAL CHARACTERISTICS
MIN
TYP
12
65
300
0.8
1.4
2.2
6.5
50
1.20
0.75
2.0
6
MAX
25
100
450
1.5
2.5
4.0
12.0
100
2.80
5.0
12
UNITS
µA
µA
µA
mA
mA
mA
mA
nA
V
V
µA
µA
dB
0.25
50
58
400
400
5
5
5
5
800
1.0
10
10
10
10
320
mA
mA
mA
µA
µA
µA
µA
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:
The shutdown pin input voltage rating is required for a low
impedance source. Internal protection devices connected to the shutdown
pin will turn on and clamp the pin to approximately 7V or –0.6V. This
range allows the use of 5V logic devices to drive the pin directly. For high
impedance sources or logic running on supply voltages greater than 5.5V,
the maximum current driven into the shutdown pin must be limited to less
than 5mA.
Note 3:
For junction temperatures greater than 110°C, a minimum load
of 1mA is recommended. For T
J
> 110°C and I
OUT
< 1mA, output voltage
may increase by 1%.
Note 4:
Operating conditions are limited by maximum junction
temperature. The regulated output voltage specification will not apply
for all possible combinations of input voltage and output current. When
operating at maximum input voltage, the output current range must be
limited. When operating at maximum output current, the input voltage
range must be limited.
Note 5:
The LT1521 (adjustable version) is tested and specified with the
adjust pin connected to the output pin.
Note 6:
Dropout voltage is the minimum input/output voltage required to
maintain regulation at the specified output current. In dropout the output
voltage will be equal to: (V
IN
– V
DROPOUT
).
Note 7:
Ground pin current is tested with V
IN
= V
OUT
(nominal) and a
current source load. This means the device is tested while operating in its
dropout region. This is the worst-case ground pin current. The ground pin
current will decrease slightly at higher input voltages.
Note 8:
Adjust pin bias current flows into the adjust pin.
Note 9:
Shutdown pin current at V
SHDN
= 0V flows out of the shutdown
pin.
Note 10:
Quiescent current in shutdown is equal to the total sum of the
shutdown pin current (2µA) and the ground pin current (4µA).
Note 11:
Reverse output current is tested with the input pin grounded and
the output pin forced to the rated output voltage. This current flows into
