LT1962 Series
300mA, Low Noise,
Micropower
LDO Regulators
FEATURES
s
s
s
s
s
s
s
s
s
s
s
DESCRIPTIO
s
s
s
s
Low Noise: 20µV
RMS
(10Hz to 100kHz)
Output Current: 300mA
Low Quiescent Current: 30µA
Wide Input Voltage Range: 1.8V to 20V
Low Dropout Voltage: 270mV
Very Low Shutdown Current: < 1
µ
A
No Protection Diodes Needed
Fixed Output Voltages: 1.5V, 1.8V, 2.5V, 3V, 3.3V, 5V
Adjustable Output from 1.22V to 20V
Stable with 3.3µF Output Capacitor
Stable with Aluminum, Tantalum or
Ceramic Capacitors
Reverse Battery Protection
No Reverse Current
Overcurrent and Overtemperature Protected
8-Lead MSOP Package
APPLICATIO S
s
s
s
Cellular Phones
Battery-Powered Systems
Noise-Sensitive Instrumentation Systems
The LT
®
1962 series are micropower, low noise, low
dropout regulators. The devices are capable of supplying
300mA of output current with a dropout voltage of 270mV.
Designed for use in battery-powered systems, the low
30µA quiescent current makes them an ideal choice.
Quiescent current is well controlled; it does not rise in
dropout as it does with many other regulators.
A key feature of the LT1962 regulators is low output noise.
With the addition of an external 0.01µF bypass capacitor,
output noise drops to 20µV
RMS
over a 10Hz to 100kHz
bandwidth. The LT1962 regulators are stable with output
capacitors as low as 3.3µF. Small ceramic capacitors can
be used without the series resistance required by other
regulators.
Internal protection circuitry includes reverse battery pro-
tection, current limiting, thermal limiting and reverse cur-
rent protection. The parts come in fixed output voltages of
1.5V, 1.8V, 2.5V, 3V, 3.3V and 5V, and as an adjustable
device with a 1.22V reference voltage. The LT1962 regu-
lators are available in the 8-lead MSOP package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
400
3.3V Low Noise Regulator
DROPOUT VOLTAGE (mV)
V
IN
3.7V TO
20V
IN
1µF
OUT
SENSE
LT1962-3.3
SHDN
GND
BYP
1962 TA01
350
3.3V AT 300mA
20µV
RMS
NOISE
10µF
300
250
200
150
100
50
0
0
50
100
150
200
LOAD CURRENT (mA)
250
300
+
0.01µF
U
Dropout Voltage
1962 TA02
U
U
1
LT1962 Series
ABSOLUTE
(Note 1)
AXI U
RATI GS
PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
TOP VIEW
OUT
SENSE/ADJ*
BYP
GND
1
2
3
4
8
7
6
5
IN
NC
NC
SHDN
IN Pin Voltage ........................................................
±20V
OUT Pin Voltage ....................................................
±20V
Input to Output Differential Voltage (Note 2) .........
±20V
SENSE Pin Voltage ...............................................
±20V
ADJ Pin Voltage ......................................................
±7V
BYP Pin Voltage....................................................
±0.6V
SHDN Pin Voltage .................................................
±20V
Output Short-Circuit Duration ......................... Indefinite
Operating Junction Temperature Range
(Note 3) ............................................ – 40°C to 125°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
MS8 PACKAGE
8-LEAD PLASTIC MSOP
*PIN 2: SENSE FOR LT1962-1.5/LT1962-1.8/
LT1962-2.5/LT1962-3/LT1962-3.3/LT1962-5.
ADJ FOR LT1962
T
JMAX
= 150°C,
θ
JA
= 125°C/ W
SEE THE APPLICATIONS
INFORMATION SECTION
FOR ADDITIONAL
INFORMATION ON
THERMAL RESISTANCE
LT1962EMS8
LT1962EMS8-1.5
LT1962EMS8-1.8
LT1962EMS8-2.5
LT1962EMS8-3
LT1962EMS8-3.3
LT1962EMS8-5
MS8 PART MARKING
LTML
LTSZ
LTTA
LTPT
LTPQ
LTPS
LTPR
Consult factory for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The
q
denotes specifications which apply over the full operating temperature range, otherwise specifications are T
A
= 25°C. (Note 3)
PARAMETER
Minimum Operating Voltage
Regulated Output Voltage
(Notes 4, 5)
CONDITIONS
(LT1962)
LT1962-1.5
LT1962-1.8
LT1962-2.5
LT1962-3
LT1962-3.3
LT1962-5
ADJ Pin Voltage
(Notes 4, 5)
Line Regulation
LT1962
LT1962-1.5
LT1962-1.8
LT1962-2.5
LT1962-3
LT1962-3.3
LT1962-5
LT1962 (Note 4)
LT1962-1.5
LT1962-1.8
I
LOAD
= 300mA (Notes 4, 12)
V
IN
= 2V, I
LOAD
= 1mA
2.5V < V
IN
< 20V, 1mA < I
LOAD
< 300mA
V
IN
= 2.3V, I
LOAD
= 1mA
2.8V < V
IN
< 20V, 1mA < I
LOAD
< 300mA
V
IN
= 3V, I
LOAD
= 1mA
3.5V < V
IN
< 20V, 1mA < I
LOAD
< 300mA
V
IN
= 3.5V, I
LOAD
= 1mA
4V < V
IN
< 20V, 1mA < I
LOAD
< 300mA
V
IN
= 3.8V, I
LOAD
= 1mA
4.3V < V
IN
< 20V, 1mA < I
LOAD
< 300mA
V
IN
= 5.5V, I
LOAD
= 1mA
6V < V
IN
< 20V, 1mA < I
LOAD
< 300mA
V
IN
= 2V, I
LOAD
= 1mA
2.3V < V
IN
< 20V, 1mA < I
LOAD
< 300mA
∆V
IN
= 2V to 20V, I
LOAD
= 1mA
∆V
IN
= 2.3V to 20V, I
LOAD
= 1mA
∆V
IN
= 3V to 20V, I
LOAD
= 1mA
∆V
IN
= 3.5V to 20V, I
LOAD
= 1mA
∆V
IN
= 3.8V to 20V, I
LOAD
= 1mA
∆V
IN
= 5.5V to 20V, I
LOAD
= 1mA
∆V
IN
= 2V to 20V, I
LOAD
= 1mA
V
IN
= 2.5V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 2.5V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 2.8V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 2.8V,
∆I
LOAD
= 1mA to 300mA
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
MIN
1.485
1.462
1.782
1.755
2.475
2.435
2.970
2.925
3.267
3.220
4.950
4.875
1.208
1.190
TYP
1.8
1.500
1.500
1.800
1.800
2.500
2.500
3.000
3.000
3.300
3.300
5.000
5.000
1.220
1.220
1
1
1
1
1
1
1
3
4
MAX
2.3
1.515
1.538
1.818
1.845
2.525
2.565
3.030
3.075
3.333
3.380
5.050
5.125
1.232
1.250
5
5
5
5
5
5
5
8
15
9
18
UNITS
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
Load Regulation
q
2
U
W
U
U
W W
W
LT1962 Series
ELECTRICAL CHARACTERISTICS
The
q
denotes specifications which apply over the full operating temperature range, otherwise specifications are T
A
= 25°C. (Note 3)
PARAMETER
Load Regulation
CONDITIONS
LT1962-2.5
LT1962-3
LT1962-3.3
LT1962-5
LT1962 (Note 4)
Dropout Voltage
V
IN
= V
OUT(NOMINAL)
(Notes 6, 7, 12)
I
LOAD
= 10mA
I
LOAD
= 10mA
I
LOAD
= 50mA
I
LOAD
= 50mA
I
LOAD
= 100mA
I
LOAD
= 100mA
I
LOAD
= 300mA
I
LOAD
= 300mA
GND Pin Current
V
IN
= V
OUT(NOMINAL)
(Notes 6, 8)
I
LOAD
= 0mA
I
LOAD
= 1mA
I
LOAD
= 50mA
I
LOAD
= 100mA
I
LOAD
= 300mA
C
OUT
= 10µF, C
BYP
= 0.01µF, I
LOAD
= 300mA, BW = 10Hz to 100kHz
(Notes 4, 9)
V
OUT
= Off to On
V
OUT
= On to Off
V
SHDN
= 0V
V
SHDN
= 20V
V
IN
= 6V, V
SHDN
= 0V
V
IN
– V
OUT
= 1.5V (Avg), V
RIPPLE
= 0.5V
P-P
, f
RIPPLE
= 120Hz,
I
LOAD
= 300mA
V
IN
= 7V, V
OUT
= 0V
V
IN
= V
OUT(NOMINAL)
+ 1V,
∆V
OUT
= – 0.1V
V
IN
= – 20V, V
OUT
= 0V
LT1962-1.5
LT1962-1.8
LT1962-2.5
LT1962-3
LT1962-3.3
LT1962-5
LT1962 (Note 4)
V
OUT
= 1.5V, V
IN
< 1.5V
V
OUT
= 1.8V, V
IN
< 1.8V
V
OUT
= 2.5V, V
IN
< 2.5V
V
OUT
= 3V, V
IN
< 3V
V
OUT
= 3.3V, V
IN
< 3.3V
V
OUT
= 5V, V
IN
< 5V
V
OUT
= 1.22V, V
IN
< 1.22V
q
q
q
q
MIN
V
IN
= 3.5V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 3.5V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 4V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 4V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 4.3V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 4.3V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 6V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 6V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 2.3V,
∆I
LOAD
= 1mA to 300mA
V
IN
= 2.3V,
∆I
LOAD
= 1mA to 300mA
q
TYP
5
7
MAX
12
25
15
30
17
33
25
50
6
12
0.15
0.21
0.20
0.28
0.24
0.33
0.33
0.43
75
120
1.6
3
12
100
2
0.5
5
1
UNITS
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
V
V
V
V
V
V
V
V
µA
µA
mA
mA
mA
µV
RMS
nA
V
V
µA
µA
µA
dB
mA
mA
q
7
q
12
q
2
q
0.10
q
0.15
q
0.18
q
0.27
q
q
q
q
q
q
30
65
1.1
2
8
20
30
0.25
0.8
0.65
0.01
1
0.1
55
65
700
320
Output Voltage Noise
ADJ Pin Bias Current
Shutdown Threshold
SHDN Pin Current
(Note 10)
Quiescent Current in Shutdown
Ripple Rejection
Current Limit
Input Reverse Leakage Current
Reverse Output Current
(Note 11)
1
10
10
10
10
10
10
5
20
20
20
20
20
20
10
mA
µA
µA
µA
µA
µA
µA
µA
Note 1:
Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2:
Absolute maximum input to output differential voltage cannot be
achieved with all combinations of rated IN pin and OUT pin voltages. With
the IN pin at 20V, the OUT pin may not be pulled below 0V. The total
measured voltage from in to out can not exceed
±20V.
Note 3:
The LT1962 regulators are tested and specified under pulse load
conditions such that T
J
≈
T
A
. The LT1962 is 100% tested at T
A
= 25°C.
Performance at – 40°C and 125°C is assured by design, characterization
and correlation with statistical process controls.
Note 4:
The LT1962 (adjustable version) is tested and specified for these
conditions with the ADJ pin connected to the OUT pin.
3
LT1962 Series
ELECTRICAL CHARACTERISTICS
Note 5:
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 6:
To satisfy requirements for minimum input voltage, the LT1962
(adjustable version) is tested and specified for these conditions with an
external resistor divider (two 250k resistors) for an output voltage of
2.44V. The external resistor divider will add a 5µA DC load on the output.
Note 7:
Dropout voltage is the minimum input to output voltage differential
needed to maintain regulation at a specified output current. In dropout, the
output voltage will be equal to: V
IN
– V
DROPOUT
.
Note 8:
GND pin current is tested with V
IN
= V
OUT(NOMINAL)
or V
IN
= 2.3V
(whichever is greater) and a current source load. This means the device is
tested while operating in its dropout region. This is the worst-case GND
pin current. The GND pin current will decrease slightly at higher input
voltages.
Note 9:
ADJ pin bias current flows into the ADJ pin.
Note 10:
SHDN pin current flows into the SHDN pin. This current is
included in the specification for GND pin current.
Note 11:
Reverse output current is tested with the IN pin grounded and the
OUT pin forced to the rated output voltage. This current flows into the OUT
pin and out the GND pin.
Note 12:
For the LT1962, LT1962-1.5 and LT1962-1.8 dropout voltage will
be limited by the minimum input voltage specification under some output
voltage/load conditions. See the curve of Minimum Input Voltage in the
Typical Performance Characteristics. For other fixed voltage versions of
the LT1962, the minimum input voltage is limited by the dropout voltage.
TYPICAL PERFOR A CE CHARACTERISTICS
Typical Dropout Voltage
400
GUARANTEED DROPOUT VOLTAGE (mV)
350
DROPOUT VOLTAGE (mV)
DROPOUT VOTLAGE (mV)
T
J
= 125°C
300
250
200
150
100
50
0
0
50
200
250
150
OUTPUT CURRENT (mA)
100
300
1962 G01
T
J
= 25°C
Quiescent Current
50
45
1.532
1.524
OUTPUT VOLTAGE (V)
QUIESCENT CURRENT (µA)
40
35
30
25
20
15
10
5
V
IN
= 6V
V
SHDN
= V
IN
R
L
=
∞
, I
L
= 0 (LT1962-1.5/-1.8
/2.5/-3/-3.3/-5)
R
L
= 250k, I
L
= 5µA (LT1962)
50
25
0
75
TEMPERATURE (°C)
100
125
1.508
1.500
1.492
1.484
1.476
1.468
–50
–25
50
75
0
25
TEMPERATURE (°C)
100
125
OUTPUT VOLTAGE (V)
0
–50 –25
4
U W
1962 G04
Guaranteed Dropout Voltage
500
450
400
350
300
250
200
150
100
50
0
0
50
250
150
200
100
OUTPUT CURRENT (mA)
300
= TEST POINTS
T
J
≤
125°C
T
J
≤
25°C
400
350
Dropout Voltage
I
L
= 300mA
300
250
200
150
100
50
0
– 50 – 25
0
I
L
= 10mA
I
L
= 1mA
75
50
25
TEMPERATURE (°C)
100
125
I
L
= 50mA
I
L
= 100mA
1962 G02
1962 G03
LT1962-1.5 Output Voltage
I
L
= 1mA
1.836
1.827
1.818
1.809
1.800
1.791
1.782
1.773
LT1962-1.8 Output Voltage
I
L
= 1mA
1.516
1.764
–50
–25
50
75
0
25
TEMPERATURE (°C)
100
125
1962 G05
1962 G06
LT1962 Series
TYPICAL PERFOR A CE CHARACTERISTICS
LT1962-2.5 Output Voltage
2.54
2.53
OUTPUT VOTLAGE (V)
I
L
= 1mA
OUTPUT VOTLAGE (V)
2.51
2.50
2.49
2.48
2.47
2.46
– 50 – 25
0
75
50
25
TEMPERATURE (°C)
100
125
3.015
3.000
2.985
2.970
2.955
2.940
– 50 – 25
0
75
50
25
TEMPERATURE (°C)
100
125
OUTPUT VOTLAGE (V)
2.52
LT1962-5 Output Voltage
5.100
5.075
I
L
= 1mA
1.240
1.235
QUIESCENT CURRENT (µA)
OUTPUT VOTLAGE (V)
ADJ PIN VOTLAGE (V)
5.050
5.025
5.000
4.975
4.950
4.925
4.900
– 50 – 25
0
75
50
25
TEMPERATURE (°C)
100
125
LT1962-1.8 Quiescent Current
800
700
QUIESCENT CURRENT (µA)
800
QUIESCENT CURRENT (µA)
600
500
400
300
200
100
0
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
V
SHDN
= 0V
V
SHDN
= V
IN
600
500
400
300
200
100
0
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
V
SHDN
= 0V
V
SHDN
= V
IN
QUIESCENT CURRENT (µA)
U W
1962 G07
LT1962-3 Output Voltage
3.060
3.045
3.030
I
L
= 1mA
LT1962-3.3 Output Voltage
3.360
3.345
3.330
3.315
3.300
3.285
3.270
3.255
3.240
– 50 – 25
0
75
50
25
TEMPERATURE (°C)
100
125
I
L
= 1mA
1962 G08
1962 G09
LT1962 ADJ Pin Voltage
I
L
= 1mA
LT1962-1.5 Quiescent Current
800
700
600
500
400
300
200
100
0
V
SHDN
= 0V
V
SHDN
= V
IN
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
T
J
= 25°C
R
L
=
∞
1.230
1.225
1.220
1.215
1.210
1.205
1.200
– 50 – 25
0
75
50
25
TEMPERATURE (°C)
100
125
1962 G10
1962 G11
1962 G12
LT1962-2.5 Quiescent Current
700
T
J
= 25°C
R
L
=
∞
800
700
600
500
400
300
200
100
0
LT1962-3 Quiescent Current
T
J
= 25°C
R
L
=
∞
T
J
= 25°C
R
L
=
∞
V
SHDN
= 0V
V
SHDN
= V
IN
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
1962 G13
1962 G14
1962 G15
5
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