Linear Technology LT1963AET-3.3, LT1963AET-1.5, LT1963AET, LT1963AEST-3.3, LT1963AEST-2.5 Datasheet

FEATURES

■

Optimized for Fast Transient Response

■

Output Current: 1.5A

■

Dropout Voltage: 340mV

■

Low Noise: 40mV

■

1mA Quiescent Current

■

No Protection Diodes Needed

■

Controlled Quiescent Current in Dropout

■

Fixed Output Voltages: 1.5V, 1.8V, 2.5V, 3.3V

■

Adjustable Output from 1.21V to 20V

■

<1mA Quiescent Current in Shutdown

■

Stable with 10mF Output Capacitor

■

Stable with Ceramic Capacitors

■

Reverse Battery Protection

■

No Reverse Current

■

Thermal Limiting

(10Hz to 100kHz)

RMS

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APPLICATIO S

■

3.3V to 2.5V Logic Power Supplies

■

Post Regulator for Switching Supplies

LT1963A Series

1.5A, Low Noise,

Fast Transient Response

LDO Regulators

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DESCRIPTIO

The LT®1963A series are low dropout regulators opti­mized for fast transient response. The devices are capable
of supplying 1.5A of output current with a dropout voltage
of 340mV. Operating quiescent current is 1mA, dropping
to < 1mA in shutdown. Quiescent current is well controlled;
it does not rise in dropout as it does with many other
regulators. In addition to fast transient response, the
LT1963A regulators have very low output noise which
makes them ideal for sensitive RF supply applications.

Output voltage range is from 1.21V to 20V. The LT1963A
regulators are stable with output capacitors as low as
10mF. Small ceramic capacitors can be used without the
necessary addition of ESR as is common with other
regulators. Internal protection circuitry includes reverse
battery protection, current limiting, thermal limiting and
reverse current protection. The devices are available in
fixed output voltages of 1.5V, 1.8V, 2.5V, 3.3V and as an
adjustable device with a 1.21V reference voltage. The
LT1963A regulators are available in 5-lead TO-220, DD,
3-lead SOT-223 and 8-lead SO packages.

, LTC and LT are registered trademarks of Linear Technology Corporation.

TYPICAL APPLICATION

3.3V to 2.5V Regulator

IN

> 3V

V

IN

10µF*

SHDN

OUT

LT1963A-2.5

SENSE

GND

1963 TA01

U

2.5V

++

*TANTALUM,
CERAMIC OR
ALUMINUM ELECTROLYTIC

1.5A

10µF*

Dropout Voltage

400

350

300

250

200

150

DROPOUT VOLTAGE (mV)

100

50

0

0.2

0

0.4
OUTPUT CURRENT (A)

0.6

0.8

1.0

1.2

1.4

1963 TA02

1.6

1963af

1

LT1963A Series

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ABSOLUTE AXI U RATI GS

(Note 1)

IN Pin Voltage........................................................ ± 20V

OUT Pin Voltage .................................................... ±20V

Input to Output Differential Voltage (Note 2) ......... ±20V

SENSE Pin Voltage ............................................... ±20V

ADJ Pin Voltage ...................................................... ±7V

UU

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PACKAGE/ORDER I FOR ATIO

FRONT VIEW

5

TAB IS

GND

5-LEAD PLASTIC DD

*PIN 5 = SENSE FOR LT1963A-1.8/LT1963A-2.5/LT1963A-3.3

= ADJ FOR LT1963A

T

JMAX

4
3
2
1

Q PACKAGE

= 150∞C, qJA = 30∞C/W

SENSE/ADJ*
OUT
GND
IN
SHDN

ORDER PART

NUMBER

LT1963AEQ
LT1963AEQ-1.5
LT1963AEQ-1.8
LT1963AEQ-2.5
LT1963AEQ-3.3

ORDER PART

NUMBER

SHDN Pin Voltage................................................. ± 20V

Output Short-Circuit Duration......................... Indefinite

Operating Junction Temperature Range –45∞C to 125∞C

Storage Temperature Range ................. –65∞C to 150∞C

Lead Temperature (Soldering, 10 sec)..................300∞C

FRONT VIEW

5
4
3
2
1

TAB IS

GND

*PIN 5 = SENSE FOR LT1963A-1.8/LT1963A-2.5/LT1963A-3.3

= ADJ FOR LT1963A

T PACKAGE

5-LEAD PLASTIC TO-220

= 150∞C, qJA = 50∞C/W

T

JMAX

SENSE/ADJ*
OUT
GND
IN
SHDN

ORDER PART

NUMBER

LT1963AET
LT1963AET-1.5
LT1963AET-1.8
LT1963AET-2.5
LT1963AET-3.3

ORDER PART

NUMBER

FRONT VIEW

TAB IS

GND

ST PACKAGE

3-LEAD PLASTIC SOT-223

T

= 150∞C, qJA = 50∞C/W

JMAX

3

OUT

2

GND

1

IN

LT1963AEST-1.5
LT1963AEST-1.8
LT1963AEST-2.5
LT1963AEST-3.3

ST PART

MARKING

963A15
963A18
963A25
963A33

Consult LTC Marketing for parts specified with wider operating temperature ranges.

TOP VIEW

OUT

1

SENSE/ADJ*

*PIN 2 = SENSE FOR LT1963A-1.8/LT1963A-2.5/LT1963A-3.3

= ADJ FOR LT1963A

2

GND

3

NC

4

S8 PACKAGE

8-LEAD PLASTIC SO

= 150∞C, qJA = 70∞C/W

T

JMAX

IN

8

GND

7

GND

6

SHDN

5

LT1963AES8
LT1963AES8-1.5
LT1963AES8-1.8
LT1963AES8-2.5
LT1963AES8-3.3

S8 PART

MARKING

1963A
963A15
963A18
963A25
963A33

2

1963af

LT1963A Series

ELECTRICAL CHARACTERISTICS

The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25∞C. (Note 2)

PARAMETER CONDITIONS MIN TYP MAX UNITS

Minimum Input Voltage (Notes 4,12) I

Regulated Output Voltage (Note 5) LT1963A-1.5 VIN = 2.21V, I

ADJ Pin Voltage LT1963A VIN = 2.21V, I
(Notes 4, 5) 2.5V < V

Line Regulation LT1963A-1.5 DVIN = 2.21V to 20V, I

Load Regulation LT1963A-1.5 VIN = 2.5V, DI

Dropout Voltage I
VIN = V

OUT(NOMINAL)

(Notes 6, 7, 12)

GND Pin Current I

= V

V

IN

OUT(NOMINAL)

+ 1V I

(Notes 6, 8)

Output Voltage Noise C
ADJ Pin Bias Current (Notes 4, 9) 3 10 mA
Shutdown Threshold V

SHDN Pin Current V
(Note 10) V

Quiescent Current in Shutdown VIN = 6V, V
Ripple Rejection VIN – V

Current Limit VIN = 7V, V

= 0.5A 1.9 V

LOAD

I

= 1.5A ● 2.1 2.5 V

LOAD

= 1mA 1.477 1.500 1.523 V

2.5V < V

LT1963A-1.8 VIN = 2.3V, I

2.8V < VIN < 20V, 1mA < I

LT1963A-2.5 VIN = 3V, I

3.5V < V

LT1963A-3.3 VIN = 3.8V, I

4.3V < V

LT1963A-1.8 DV
LT1963A-2.5 DV

IN
IN

LT1963A-3.3 DVIN = 3.8V to 20V, I
LT1963A (Note 4) DV

IN

= 2.5V, DI

V

IN

LT1963A-1.8 VIN = 2.8V, DI

= 2.8V, DI

V

IN

LT1963A-2.5 VIN = 3.5V, DI

= 3.5V, DI

V

IN

LT1963A-3.3 VIN = 4.3V, DI

= 4.3V, DI

V

IN

LT1963A (Note 4) VIN = 2.5V, DI

= 2.5V, DI

V

IN

= 1mA 0.02 0.06 V

LOAD

I

= 1mA ● 0.10 V

LOAD

I

= 100mA 0.10 0.17 V

LOAD

I

= 100mA ● 0.22 V

LOAD

I

= 500mA 0.19 0.27 V

LOAD

I

= 500mA ● 0.35 V

LOAD

I

= 1.5A 0.34 0.45 V

LOAD

I

= 1.5A ● 0.55 V

LOAD

= 0mA ● 1.0 1.5 mA

LOAD

= 1mA ● 1.1 1.6 mA

LOAD

I

= 100mA ● 3.8 5.5 mA

LOAD

I

= 500mA ● 15 25 mA

LOAD

= 1.5A ● 80 120 mA

I

LOAD

= 10mF, I

OUT

= Off to On ● 0.90 2 V

OUT

= On to Off ● 0.25 0.75 V

V

OUT

= 0V 0.01 1 mA

SHDN

= 20V 3 30 mA

SHDN

OUT

= 120Hz, I

f

RIPPLE

= V

V

IN

OUT(NOMINAL)

= 1.5A, BW = 10Hz to 100kHz 40 mV

LOAD

= 0V 0.01 1 mA

SHDN

= 1.5V (Avg), V

= 0.75A

LOAD

= 0V 2 A

OUT

+ 1V, DV

LOAD

< 20V, 1mA < I

IN

= 1mA 1.773 1.800 1.827 V

LOAD

= 1mA 2.462 2.500 2.538 V

LOAD

< 20V, 1mA < I

IN

= 1mA 3.250 3.300 3.350 V

LOAD

< 20V, 1mA < I

IN

= 1mA 1.192 1.210 1.228 V

LOAD

< 20V, 1mA < I

IN

= 2.3V to 20V, I
= 3V to 20V, I

LOAD

LOAD

LOAD

= 2.21V to 20V, I

= 1mA to 1.5A 2 9 mV

LOAD

= 1mA to 1.5A ● 18 mV

LOAD

= 1mA to 1.5A 2 10 mV

LOAD

= 1mA to 1.5A ● 20 mV

LOAD

= 1mA to 1.5A 2.5 15 mV

LOAD

= 1mA to 1.5A ● 30 mV

LOAD

= 1mA to 1.5A 3 20 mV

LOAD

= 1mA to 1.5A ● 35 mV

LOAD

= 1mA to 1.5A 2 8 mV

LOAD

= 1mA to 1.5A ● 15 mV

LOAD

= 0.5V

RIPPLE

OUT

P-P

= –0.1V ● 1.6 A

< 1.5A ● 1.447 1.500 1.545 V

LOAD

< 1.5A ● 1.737 1.800 1.854 V

LOAD

< 1.5A ● 2.412 2.500 2.575 V

LOAD

< 1.5A ● 3.200 3.300 3.400 V

LOAD

< 1.5A ● 1.174 1.210 1.246 V

LOAD

= 1mA ● 2.0 6 mV

LOAD

= 1mA ● 2.5 7 mV

= 1mA ● 3.0 10 mV

= 1mA ● 3.5 10 mV

= 1mA ● 1.5 5 mV

LOAD

,5563dB

RMS

1963af

3

LT1963A Series

TEMPERATURE (°C)

–50

DROPOUT VOLTAGE (mV)

500
450
400
350
300
250
200
150
100

50

0

0

50

75

1963 G03

–25

25

100

125

IL = 100mA

IL = 1mA

IL = 0.5A

IL = 1.5A

ELECTRICAL CHARACTERISTICS

The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25∞C. (Note 2)

PARAMETER CONDITIONS MIN TYP MAX UNITS

Input Reverse Leakage Current (Note 13) Q, T, S8 Packages VIN = –20V, V

ST Package VIN = –20V, V

Reverse Output Current (Note 11) LT1963A-1.5 V

LT1963A-1.8 V
LT1963A-2.5 V
LT1963A-3.3 V
LT1963A (Note 4) V

= 1.5V, VIN < 1.5V 600 1200 mA

OUT

= 1.8V, VIN < 1.8V 600 1200 mA

OUT

= 2.5V, VIN < 2.5V 600 1200 mA

OUT

= 3.3V, VIN < 3.3V 600 1200 mA

OUT

= 1.21V, VIN < 1.21V 300 600 mA

OUT

= 0V ● 1mA

OUT

= 0V ● 2mA

OUT

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 can not 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 LT1963A regulators are tested and specified under pulse load
conditions such that T
TA = 25∞C. Performance at –40∞C and 125∞C is assured by design,
characterization and correlation with statistical process controls.

Note 4: The LT1963A (adjustable version) is tested and specified for these
conditions with the ADJ pin connected to the OUT pin.

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 LT1963A
(adjustable version) is tested and specified for these conditions with an

TYPICAL PERFOR A CE CHARACTERISTICS

Typical Dropout Voltage

500
450
400
350
300
250
200
150

DROPOUT VOLTAGE (mV)

100

50

0

4

0

0.2 0.6

ª TA. The LT1963A is 100% tested at

J

TJ = 125°C

TJ = 25°C

1.4

1.0

1.2

1.6

1963 • G01

0.4

0.8

OUTPUT CURRENT (A)

UW

Guaranteed Dropout Voltage

600

TEST POINTS

500

400

300

200

100

GUARANTEED DROPOUT VOLTAGE (mV)

0

0

0.2 0.6

0.4

external resistor divider (two 4.12k resistors) for an output voltage of

2.4V. The external resistor divider will add a 300mA 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

Note 8: GND pin current is tested with V
current source load. The GND pin current will decrease 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.
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 LT1963A, LT1963A-1.5 and LT1963A-1.8 dropout voltage
will be limited by the minimum input voltage specification under some
output voltage/load conditions.

Note 13. For the ST package, the input reverse leakage current increases
due to the additional reverse leakage current for the SHDN pin, which is
tied internally to the IN pin.

TJ ≤ 125°C

TJ ≤ 25°C

0.8

OUTPUT CURRENT (A)

1.0

1.2

1.4

1963 • G02

1.6

IN

– V

DROPOUT

= V

IN

.

OUT(NOMINAL)

Dropout Voltage

+ 1V and a

1963af

UW

TYPICAL PERFOR A CE CHARACTERISTICS

LT1963A Series

Quiescent Current

1.4

1.2

LT1963A-1.5/1.8/-2.5/-3.3

1.0

0.8

0.6

0.4

QUIESCENT CURRENT (mA)

VIN = 6V

0.2

= ∞, IL = 0

R

L

= V

V

SHDN

0

–50

IN

–25 0

25 75

TEMPERATURE (°C)

LT1963A-2.5 Output Voltage

2.58
IL = 1mA

2.56

2.54

2.52

2.50

2.48

OUTPUT VOLTAGE (V)

2.46

2.44

2.42

–50

050

–25 25 75 125

TEMPERATURE (°C)

LT1963A

50 100 125

1963 G04

100

1963 G06

LT1963A-1.5 Output Voltage

1.54
IL = 1mA

1.53

1.52

1.51

1.50

1.49

OUTPUT VOLTAGE (V)

1.48

1.47

1.46

–25 0 50

–50

25

TEMPERATURE (°C)

LT1963A-3.3 Output Voltage

3.38
IL = 1mA

3.36

3.34

3.32

3.30

3.28

OUTPUT VOLTAGE (V)

3.26

3.24

3.22

–50

050

–25 25 75 125

TEMPERATURE (°C)

75 100 125

1963 G40

100

1963 G07

LT1963A-1.8 Output Voltage

1.84
IL = 1mA

1.83

1.82

1.81

1.80

1.79

OUTPUT VOLTAGE (V)

1.78

1.77

1.76

–25 25 75 125

–50

050

TEMPERATURE (°C)

LT1963A ADJ Pin Voltage

1.230
IL = 1mA

1.225

1.220

1.215

1.210

1.205

ADJ PIN VOLTAGE (V)

1.200

1.195

1.190

–50

050

–25 25 75 125

TEMPERATURE (°C)

100

1963 G05

100

1963 G08

LT1963A-1.5 Quiescent Current

14

TJ = 25°C

= ∞

R

L

12

10

QUIESCENT CURRENT (mA)

= V

V

SHDN

IN

8

6

4

2

0

0

2

1

3

5

68

4

INPUT VOLTAGE (V)

LT1963A-1.8 Quiescent Current

14

12

10

8

6

4

QUIESCENT CURRENT (mA)

2

9

1963 G41

10

7

0

0

2

1

34
INPUT VOLTAGE (V)

TJ = 25°C

= ∞

R

L

= V

V

SHDN

IN

5678910

1963 G09

LT1963A-2.5 Quiescent Current

14

12

10

8

6

4

QUIESCENT CURRENT (mA)

2

0

0

2

1

34
INPUT VOLTAGE (V)

TJ = 25°C

= ∞

R

L

= V

V

SHDN

IN

1056789

1963 G10

1963af

5

LT1963A Series

INPUT VOLTAGE (V)

100

90
80
70
60
50
40
30
20
10

0

GND PIN CURRENT (mA)

1963 G17

0123

4

5

678910

RL = 1.8, IL = 1A*

RL = 1.2, IL = 1.5A*

RL = 3.6, IL = 500mA*

TJ = 25°C
V

SHDN

= V

IN

*FOR V

OUT

= 1.8V

UW

TYPICAL PERFOR A CE CHARACTERISTICS

LT1963A-3.3 Quiescent Current

14

12

10

8

6

4

QUIESCENT CURRENT (mA)

2

0

0

2

1

34
INPUT VOLTAGE (V)

LT1963A-1.8 GND Pin Current

25

TJ = 25°C

= V

V

SHDN

IN

*FOR V

20

15

10

GND PIN CURRENT (mA)

5

0

0

= 1.8V

OUT

RL = 18, IL = 100mA*

RL = 180, IL = 10mA*

1

3

2

INPUT VOLTAGE (V)

RL = 6, IL = 300mA*

4

TJ = 25°C

= ∞

R

L

= V

V

SHDN

IN

1963 G11

1963 G13

QUIESCENT CURRENT (mA)

1056789

GND PIN CURRENT (mA)

1098765

LT1963A Quiescent Current

14

12

10

8

6

4

2

0

0

4

2

68
INPUT VOLTAGE (V)

LT1963A-2.5 GND Pin Current

25

20

15

10

5

0

0

RL = 8.33, IL = 300mA*

RL = 25, IL = 100mA*

RL = 250, IL = 10mA*

1

3

2

INPUT VOLTAGE (V)

TJ = 25°C
V

SHDN

*FOR V

4

TJ = 25°C

= 4.3k

R

L

= V

V

SHDN

= V

IN

= 2.5V

OUT

IN

1963 G12

1963 G14

GND PIN CURRENT (mA)

2010 12 14 16 18

GND PIN CURRENT (mA)

1098765

LT1963A-1.5 GND Pin Current

25

TJ = 25°C

= V

V

SHDN

IN

*FOR V

20

15

10

5

0

0

= 1.5V

OUT

RL = 150, IL = 10mA*

123

45

INPUT VOLTAGE (V)

RL = 5, IL = 300mA*

RL = 15, IL = 100mA*

67 9

LT1963A-3.3 GND Pin Current

25

20

15

10

5

0

0

RL = 330, IL = 100mA*

1

3

2

INPUT VOLTAGE (V)

TJ = 25°C
V

SHDN

*FOR V

RL = 11, IL = 300mA*

RL = 33, IL = 100mA*

4

= V

OUT

8

IN

= 3.3V

10

1963 G42

1098765

1963 G15

10

8

6

4

GND PIN CURRENT (mA)

2

0

6

LT1963A GND Pin Current

TJ = 25°C

= V

V

SHDN

*FOR V

RL = 4.33, IL = 300mA*

RL = 12.1, IL = 100mA*

RL = 121, IL = 10mA*

1

0

2

3

4

INPUT VOLTAGE (V)

OUT

IN

= 1.21V

1963 G16

LT1963A-1.8 GND Pin CurrentLT1963A-1.5 GND Pin Current

100

90
80
70
60
50
40
30

GND PIN CURRENT (mA)

20
10

1098765

0

0

RL = 1, IL = 1.5A*

21

INPUT VOLTAGE (V)

TJ = 25°C
V

SHDN

*FOR V

RL = 1.5, IL = 1A*

RL = 3, IL = 500mA*

67 9

43

5

= V

OUT

IN

= 1.5V

8

10

1963 G43

1963af