LT1963AEFE-2.5#TRPBF [Linear]
LT1963A Series - 1.5A, Low Noise, Fast Transient Response LDO Regulators; Package: TSSOP; Pins: 16; Temperature Range: -40°C to 85°C;型号: | LT1963AEFE-2.5#TRPBF |
厂家: | Linear |
描述: | LT1963A Series - 1.5A, Low Noise, Fast Transient Response LDO Regulators; Package: TSSOP; Pins: 16; Temperature Range: -40°C to 85°C 光电二极管 输出元件 调节器 |
文件: | 总28页 (文件大小:613K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
LT1963A Series
1.5A, Low Noise,
Fast Transient Response
LDO Regulators
FeaTures
DescripTion
TheLT ®1963Aseriesarelowdropoutregulatorsoptimized
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
<1µA in shutdown. Quiescent current is well controlled; it
does not rise in dropout as it does with many other regula-
tors. In addition to fast transient response, the LT1963A
regulators have very low output noise which makes them
ideal for sensitive RF supply applications.
n
Optimized for Fast Transient Response
n
Output Current: 1.5A
n
Dropout Voltage: 340mV
n
Low Noise: 40µV
1mA Quiescent Current
(10Hz to 100kHz)
RMS
n
n
n
n
n
n
n
n
n
n
n
n
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
<1µA Quiescent Current in Shutdown
Stable with 10µF Output Capacitor*
Stable with Ceramic Capacitors*
Reverse Battery Protection
Output voltage range is from 1.21V to 20V. The LT1963A
regulators are stable with output capacitors as low as
10µF. Internal protection circuitry includes reverse bat-
tery 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, 8-lead SO and 16-lead TSSOP packages.
No Reverse Current
Thermal Limiting
5-Lead TO-220, DD, 3-Lead SOT-223 and
8-Lead SO Packages
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners. Protected by U.S. Patents including 6118263, 6144250.
applicaTions
n
3.3V to 2.5V Logic Power Supplies
*See Applications Information Section.
n
Post Regulator for Switching Supplies
Typical applicaTion
Dropout Voltage
400
3.3V to 2.5V Regulator
350
300
250
200
150
100
50
2.5V
1.5A
IN
OUT
+
+
V
> 3V
10µF*
10µF*
IN
LT1963A-2.5
SHDN SENSE
GND
*TANTALUM,
CERAMIC OR
ALUMINUM ELECTROLYTIC
1963A TA01
0
0.8 1.0
0
0.2 0.4 0.6
1.2 1.4 1.6
OUTPUT CURRENT (A)
1963A TA02
1963aff
1
For more information www.linear.com/LT1963A
LT1963A Series
absoluTe MaxiMuM raTings
(Note 1)
Operating Junction Temperature Range (Note 3)
IN Pin Voltage ........................................................ ±20V
OUT Pin Voltage......................................................±20V
Input to Output Differential Voltage (Note 2)...........±20V
SENSE Pin Voltage ............................................... ±20V
ADJ Pin Voltage ...................................................... ±±V
SHDN Pin Voltage ................................................. ±20V
Output Short-Circuit Duration ........................ Indefinite
LT1963AE...........................................–40°C to 125°C
LT1963AI............................................–40°C to 125°C
LT1963AMP .......................................–55°C to 125°C
Storage Temperature Range...................–65°C to 150°C
Lead Temperature (Soldering, 10 sec) .................. 300°C
pin conFiguraTion
TOP VIEW
GND
NC
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
GND
NC
FRONT VIEW
FRONT VIEW
OUT
IN
SENSE/
ADJ*
5
4
3
2
1
SENSE/ADJ*
OUT
5
4
3
2
1
OUT
IN
17
OUT
GND
IN
OUT
IN
TAB IS
GND
GND
SENSE/ADJ*
GND
NC
IN
SHDN
GND
SHDN
SHDN
GND
Q PACKAGE
5-LEAD PLASTIC DD
TAB IS
GND
T PACKAGE
5-LEAD PLASTIC TO-220
FE PACKAGE
*PIN 5 = SENSE FOR LT1963A-1.5/LT1963A-1.8/
LT1963A-2.5/LT1963A-3.3
*PIN 5 = SENSE FOR LT1963A-1.5/LT1963A-1.8/
LT1963A-2.5/LT1963A-3.3
16-LEAD PLASTIC TSSOP
EXPOSED PAD (PIN 17) IS GND. MUST BE
= ADJ FOR LT1963A
SOLDERED TO THE PCB.
= ADJ FOR LT1963A
*PIN 6 = SENSE FOR LT1963A-1.5/LT1963A-1.8/
LT1963A-2.5/LT1963A-3.3
T
= 150°C, θ = 50°C/ W
T
= 150°C, θ = 30°C/ W
JMAX
JA
JMAX
JA
= ADJ FOR LT1963A
= 150°C, θ = 38°C/ W
T
JMAX
JA
FRONT VIEW
TOP VIEW
OUT
SENSE/ADJ*
GND
1
2
3
4
8
7
6
5
IN
3
2
1
OUT
GND
IN
GND
GND
SHDN
TAB IS
GND
NC
S8 PACKAGE
ST PACKAGE
3-LEAD PLASTIC SOT-223
= 150°C, θ = 50°C/ W
8-LEAD PLASTIC SO
*PIN 2 = SENSE FOR LT1963A-1.5/LT1963A-1.8/
LT1963A-2.5/LT1963A-3.3
T
JMAX
JA
= ADJ FOR LT1963A
T
= 150°C, θ = ±0°C/ W
JMAX
JA
1963aff
2
For more information www.linear.com/LT1963A
LT1963A Series
orDer inForMaTion
LEAD FREE FINISH
TAPE AND REEL
PART MARKING*
LT1963AEQ
LT1963AIQ
LT1963AMPQ
LT1963AEQ-1.5
LT1963AEQ-1.8
LT1963AEQ-2.5
LT1963AEQ-3.3
LT1963AET
LT1963AIT
PACKAGE DESCRIPTION
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–55°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–55°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–55°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
LT1963AEQ#PBF
LT1963AEQ#TRPBF
LT1963AIQ#TRPBF
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic TO-220
5-Lead Plastic TO-220
5-Lead Plastic TO-220
5-Lead Plastic TO-220
5-Lead Plastic TO-220
5-Lead Plastic TO-220
16-Lead Plastic TSSOP
16-Lead Plastic TSSOP
16-Lead Plastic TSSOP
16-Lead Plastic TSSOP
16-Lead Plastic TSSOP
16-Lead Plastic TSSOP
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
8-Lead Plastic SO
LT1963AIQ#PBF
LT1963AMPQ#PBF
LT1963AEQ-1.5#PBF
LT1963AEQ-1.8#PBF
LT1963AEQ-2.5#PBF
LT1963AEQ-3.3#PBF
LT1963AET#PBF
LT1963AMPQ#TRPBF
LT1963AEQ-1.5#TRPBF
LT1963AEQ-1.8#TRPBF
LT1963AEQ-2.5#TRPBF
LT1963AEQ-3.3#TRPBF
LT1963AET#TRPBF
LT1963AIT#PBF
LT1963AIT#TRPBF
LT1963AET-1.5#PBF
LT1963AET-1.8#PBF
LT1963AET-2.5#PBF
LT1963AET-3.3#PBF
LT1963AEFE#PBF
LT1963AIFE#PBF
LT1963AEFE-1.5#PBF
LT1963AEFE-1.8#PBF
LT1963AEFE-2.5#PBF
LT1963AEFE-3.3#PBF
LT1963AEST-1.5#PBF
LT1963AEST-1.8#PBF
LT1963AEST-2.5#PBF
LT1963AEST-3.3#PBF
LT1963AES8#PBF
LT1963AIS8#PBF
LT1963AMPS8#PBF
LT1963AES8-1.5#PBF
LT1963AES8-1.8#PBF
LT1963AES8-2.5#PBF
LT1963AES8-3.3#PBF
LEAD BASED FINISH
LT1963AEQ
LT1963AET-1.5#TRPBF
LT1963AET-1.8#TRPBF
LT1963AET-2.5#TRPBF
LT1963AET-3.3#TRPBF
LT1963AEFE#TRPBF
LT1963AIFE#TRPBF
LT1963AEFE-1.5#TRPBF
LT1963AEFE-1.8#TRPBF
LT1963AEFE-2.5#TRPBF
LT1963AEFE-3.3#TRPBF
LT1963AEST-1.5#TRPBF
LT1963AEST-1.8#TRPBF
LT1963AEST-2.5#TRPBF
LT1963AEST-3.3#TRPBF
LT1963AES8#TRPBF
LT1963AIS8#TRPBF
LT1963AMPS8#TRPBF
LT1963AES8-1.5#TRPBF
LT1963AES8-1.8#TRPBF
LT1963AES8-2.5#TRPBF
LT1963AES8-3.3#TRPBF
TAPE AND REEL
LT1963AET-1.5
LT1963AET-1.8
LT1963AET-2.5
LT1963AET-3.3
1963AEFE
1963AIFE
1963AEFE15
1963AEFE18
1963AEFE25
1963AEFE33
963A15
963A18
963A25
963A33
1963A
1963A
8-Lead Plastic SO
963AMP
8-Lead Plastic SO
963A15
8-Lead Plastic SO
963A18
8-Lead Plastic SO
963A25
8-Lead Plastic SO
963A33
8-Lead Plastic SO
PART MARKING*
LT1963AEQ
LT1963AIQ
LT1963AMPQ
LT1963AEQ-1.5
LT1963AEQ-1.8
LT1963AEQ-2.5
LT1963AEQ-3.3
LT1963AET
LT1963AIT
PACKAGE DESCRIPTION
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic DD-Pak
5-Lead Plastic TO-220
5-Lead Plastic TO-220
LT1963AEQ#TR
LT1963AIQ
LT1963AIQ#TR
LT1963AMPQ
LT1963AMPQ#TR
LT1963AEQ-1.5
LT1963AEQ-1.5#TR
LT1963AEQ-1.8#TR
LT1963AEQ-2.5#TR
LT1963AEQ-3.3#TR
LT1963AET#TR
LT1963AEQ-1.8
LT1963AEQ-2.5
LT1963AEQ-3.3
LT1963AET
LT1963AIT
LT1963AIT#TR
1963aff
3
For more information www.linear.com/LT1963A
LT1963A Series
orDer inForMaTion
LEAD BASED FINISH
LT1963AET-1.5
LT1963AET-1.8
LT1963AET-2.5
LT1963AET-3.3
LT1963AEFE
TAPE AND REEL
PART MARKING*
LT1963AET-1.5
LT1963AET-1.8
LT1963AET-2.5
LT1963AET-3.3
1963AEFE
1963AIFE
PACKAGE DESCRIPTION
5-Lead Plastic TO-220
5-Lead Plastic TO-220
5-Lead Plastic TO-220
5-Lead Plastic TO-220
16-Lead Plastic TSSOP
16-Lead Plastic TSSOP
16-Lead Plastic TSSOP
16-Lead Plastic TSSOP
16-Lead Plastic TSSOP
16-Lead Plastic TSSOP
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
3-Lead Plastic SOT-223
8-Lead Plastic SO
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–55°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
LT1963AET-1.5#TR
LT1963AET-1.8#TR
LT1963AET-2.5#TR
LT1963AET-3.3#TR
LT1963AEFE#TR
LT1963AIFE
LT1963AIFE#TR
LT1963AEFE-1.5
LT1963AEFE-1.8
LT1963AEFE-2.5
LT1963AEFE-3.3
LT1963AEST-1.5
LT1963AEST-1.8
LT1963AEST-2.5
LT1963AEST-3.3
LT1963AES8
LT1963AEFE-1.5#TR
LT1963AEFE-1.8#TR
LT1963AEFE-2.5#TR
LT1963AEFE-3.3#TR
LT1963AEST-1.5#TR
LT1963AEST-1.8#TR
LT1963AEST-2.5#TR
LT1963AEST-3.3#TR
LT1963AES8#TR
1963AEFE15
1963AEFE18
1963AEFE25
1963AEFE33
963A15
963A18
963A25
963A33
1963A
LT1963AIS8
LT1963AIS8#TR
1963A
8-Lead Plastic SO
LT1963AMPS8
LT1963AES8-1.5
LT1963AES8-1.8
LT1963AES8-2.5
LT1963AES8-3.3
LT1963AMPS8#TR
LT1963AES8-1.5#TR
LT1963AES8-1.8#TR
LT1963AES8-2.5#TR
LT1963AES8-3.3#TR
963AMP
8-Lead Plastic SO
963A15
8-Lead Plastic SO
963A18
8-Lead Plastic SO
963A25
8-Lead Plastic SO
963A33
8-Lead Plastic SO
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
1963aff
4
For more information www.linear.com/LT1963A
LT1963A Series
The l denotes specifications which apply over the full operating
elecTrical characTerisTics
temperature range, otherwise specifications are at TA = 25°C. (Note 3)
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Minimum Input Voltage (Notes 4,12)
I
I
= 0.5A
= 1.5A
1.9
2.1
V
V
LOAD
LOAD
l
l
l
l
l
l
2.5
Regulated Output Voltage (Note 5)
LT1963A-1.5
LT1963A-1.8
LT1963A-2.5
LT1963A-3.3
LT1963A
V
= 2.21V, I
= 1mA
1.4±±
1.44±
1.500
1.500
1.523
1.545
V
V
IN
LOAD
2.5V < V < 20V, 1mA < I
< 1.5A
< 1.5A
< 1.5A
< 1.5A
< 1.5A
IN
LOAD
LOAD
LOAD
LOAD
LOAD
V
= 2.3V, I
= 1mA
LOAD
1.±±3
1.±3±
1.800
1.800
1.82±
1.854
V
V
IN
2.8V < V < 20V, 1mA < I
IN
V
= 3V, I
= 1mA
LOAD
2.462
2.412
2.500
2.500
2.538
2.5±5
V
V
IN
3.5V < V < 20V, 1mA < I
IN
V
= 3.8V, I
= 1mA
LOAD
3.250
3.200
3.300
3.300
3.350
3.400
V
V
IN
4.3V < V < 20V, 1mA < I
IN
ADJ Pin Voltage (Notes 4, 5)
Line Regulation
V
IN
= 2.21V, I
= 1mA
1.192
1.1±4
1.210
1.210
1.228
1.246
V
V
LOAD
2.5V < V < 20V, 1mA < I
IN
l
l
l
l
l
LT1963A-1.5
LT1963A-1.8
LT1963A-2.5
LT1963A-3.3
∆V = 2.21V to 20V, I
= 1mA
2.0
2.5
3.0
3.5
1.5
6
±
10
10
5
mV
mV
mV
mV
mV
IN
LOAD
∆V = 2.3V to 20V, I
= 1mA
IN
LOAD
LOAD
∆V = 3V to 20V, I
= 1mA
IN
∆V = 3.8V to 20V, I
= 1mA
= 1mA
IN
LOAD
LOAD
LT1963A (Note 4) ∆V = 2.21V to 20V, I
IN
Load Regulation
LT1963A-1.5
LT1963A-1.8
LT1963A-2.5
LT1963A-3.3
LT1963A (Note 4)
V
V
= 2.5V, ∆I
= 2.5V, ∆I
= 1mA to 1.5A
= 1mA to 1.5A
2
9
mV
mV
IN
IN
LOAD
LOAD
●
●
●
●
●
●
●
●
●
18
V
V
= 2.8V, ∆I
= 2.8V, ∆I
= 1mA to 1.5A
= 1mA to 1.5A
2
10
20
mV
mV
IN
IN
LOAD
LOAD
V
V
= 3.5V, ∆I
= 3.5V, ∆I
= 1mA to 1.5A
= 1mA to 1.5A
2.5
3
15
30
mV
mV
IN
IN
LOAD
LOAD
V
V
= 4.3V, ∆I
= 4.3V, ∆I
= 1mA to 1.5A
= 1mA to 1.5A
20
35
mV
mV
IN
IN
LOAD
LOAD
V
V
= 2.5V, ∆I
= 2.5V, ∆I
= 1mA to 1.5A
= 1mA to 1.5A
2
8
15
mV
mV
IN
IN
LOAD
LOAD
Dropout Voltage
= V
I
I
= 1mA
= 1mA
0.02
0.10
0.19
0.34
0.06
0.10
V
V
LOAD
LOAD
V
IN
OUT(NOMINAL)
(Notes 6, ±, 12)
I
I
= 100mA
= 100mA
0.1±
0.22
V
V
LOAD
LOAD
I
I
= 500mA
= 500mA
0.2±
0.35
V
V
LOAD
LOAD
I
I
= 1.5A
= 1.5A
0.45
0.55
V
V
LOAD
LOAD
GND Pin Current
I
I
I
I
I
= 0mA
●
●
●
●
●
1.0
1.1
3.8
15
1.5
1.6
5.5
25
mA
mA
mA
mA
mA
LOAD
LOAD
LOAD
LOAD
LOAD
V
= V
+ 1V
= 1mA
IN
OUT(NOMINAL)
(Notes 6, 8)
= 100mA
= 500mA
= 1.5A
80
120
Output Voltage Noise
ADJ Pin Bias Current
Shutdown Threshold
C
= 10µF, I
= 1.5A, BW = 10Hz to 100kHz
40
3
µV
RMS
OUT
LOAD
(Notes 4, 9)
10
2
µA
V
OUT
V
OUT
= Off to On
= On to Off
●
●
0.90
0.±5
V
V
0.25
SHDN Pin Current (Note 10)
V
SHDN
V
SHDN
= 0V
= 20V
0.01
3
1
30
µA
µA
Quiescent Current in Shutdown
V
IN
= 6V, V
= 0V
SHDN
0.01
1
µA
1963aff
5
For more information www.linear.com/LT1963A
LT1963A Series
The l denotes specifications which apply over the full operating
elecTrical characTerisTics
temperature range, otherwise specifications are at TA = 25°C. (Note 3)
PARAMETER
CONDITIONS
– V = 1.5V (Avg), V
MIN
TYP
MAX
UNITS
Ripple Rejection
V
= 0.5V ,
P-P
55
63
dB
IN
OUT
RIPPLE
f
= 120Hz, I
= 0.±5A
RIPPLE
LOAD
Current Limit
V
IN
V
IN
= ±V, V
= 0V
2
A
A
OUT
●
= V
+ 1V, ∆V
= –0.1V
1.6
OUT(NOMINAL)
OUT
Input Reverse Leakage Current (Note 13) Q, T, S8 Packages
ST Package
V
IN
V
IN
= –20V, V
= –20V, V
= 0
= 0
●
●
1
2
mA
mA
OUT
OUT
Reverse Output Current (Note 11)
LT1963A-1.5
LT1963A-1.8
LT1963A-2.5
LT1963A-3.3
LT1963A (Note 4)
V
OUT
V
OUT
V
OUT
V
OUT
V
OUT
= 1.5V, V < 1.5V
600
600
600
600
300
1200
1200
1200
1200
600
µA
µA
µA
µA
µA
IN
= 1.8V, V < 1.8V
IN
= 2.5V, V < 2.5V
IN
= 3.3V, V < 3.3V
IN
= 1.21V, V < 1.21V
IN
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: 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 6: To satisfy requirements for minimum input voltage, the LT1963A
(adjustable version) is tested and specified for these conditions with an
external resistor divider (two 4.12k resistors) for an output voltage of 2.4V.
The external resistor divider will add a 300µA 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 – V
.
IN
DROPOUT
Note 8: GND pin current is tested with V = V
+ 1V and a
IN
OUT(NOMINAL)
current source load. The GND pin current will decrease at higher input
voltages.
Note 3: The LT1963A regulators are tested and specified under pulse load
conditions such that T ≈ T . The LT1963AE is 100% tested at T = 25°C.
J
A
A
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.
Performance at –40°C and 125°C is assured by design, characterization and
correlation with statistical process controls. The LT1963AI is guaranteed
over the full –40°C to 125°C operating junction temperature range. The
LT1963AMP is 100% tested and guaranteed over the –55°C to 125°C
operating junction temperature range.
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.
1963aff
6
For more information www.linear.com/LT1963A
LT1963A Series
Typical perForMance characTerisTics
Typical Dropout Voltage
Guaranteed Dropout Voltage
Dropout Voltage
500
450
400
350
300
250
200
150
100
50
500
450
400
350
300
250
200
150
100
50
600
500
400
300
200
100
0
= TEST POINTS
T ≤ 125°C
J
T = 125°C
J
I
= 1.5A
L
T ≤ 25°C
J
T = 25°C
J
I
= 0.5A
L
I
= 100mA
L
I
= 1mA
L
0
0
0
1.4
0
0.8
1.2 1.4
0.2 0.4 0.6 0.8 1.0 1.2
OUTPUT CURRENT (A)
1.6
0.2 0.4 0.6
1.0
1.6
–50
0
25
50
75 100 125
–25
OUTPUT CURRENT (A)
TEMPERATURE (°C)
1963A G01
1963A G02
1963A G03
Quiescent Current
LT1963A-1.8 Output Voltage
LT1963A-1.5 Output Voltage
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
1.54
1.84
1.83
1.82
1.81
1.80
1.79
1.78
1.77
1.76
I
L
= 1mA
I
L
= 1mA
1.53
1.52
LT1963A-1.5/1.8/-2.5/-3.3
1.51
1.50
1.49
1.48
1.47
LT1963A
V
= 6V
IN
L
R
= ∞, I = 0
L
V
= V
IN
SHDN
1.46
25
50
TEMPERATURE (°C)
75
100 125
–50 –25
0
–25
0
25
50
75
125
–50
100
–25
0
50
75 100 125
–50
25
TEMPERATURE (°C)
TEMPERATURE (°C)
1963A G04
1963A G05
1963A G40
LT1963A-2.5 Output Voltage
LT1963A-3.3 Output Voltage
LT1963A ADJ Pin Voltage
2.58
2.56
2.54
2.52
2.50
2.48
2.46
2.44
2.42
3.38
3.36
3.34
3.32
3.30
3.28
3.26
3.24
3.22
1.230
1.225
1.220
1.215
1.210
1.205
1.200
1.195
1.190
I
L
= 1mA
I
= 1mA
I = 1mA
L
L
–25
0
25
50
75
125
–25
0
25
50
75
125
–25
0
25
50
75
125
–50
100
–50
100
–50
100
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
1963A G06
1963A G07
1963A G08
1963aff
7
For more information www.linear.com/LT1963A
LT1963A Series
Typical perForMance characTerisTics
LT1963A-2.5 Quiescent Current
LT1963A-1.5 Quiescent Current
LT1963A-1.8 Quiescent Current
14
12
14
12
10
8
14
12
10
8
T = 25°C
J
T = 25°C
J
T = 25°C
J
R
V
= ∞
R
V
= ∞
L
R
V
= ∞
L
L
= V
= V
SHDN
IN
= V
SHDN
IN
SHDN
IN
10
8
6
4
2
6
6
4
4
2
2
0
0
0
5
6
7
8
9
10
0
3
5
6
7
8
9
10
0
3
4
5
6
7
8
9
10
0
1
2
3
4
1
2
4
1
2
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
1963A G09
1963A G10
1963A G41
LT1963A Quiescent Current
LT1963A-1.5 GND Pin Current
LT1963A-3.3 Quiescent Current
25
20
15
14
12
10
8
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
T = 25°C
J
T = 25°C
J
T = 25°C
J
R
V
= V
IN
R
V
= ∞
SHDN
= 4.3k
L
L
*FOR V
= 1.5V
= V
OUT
V
= V
SHDN
IN
SHDN
IN
R
L
= 150, I = 10mA*
L
6
R
L
= 5, I = 300mA*
L
10
5
4
R
L
= 15, I = 100mA*
L
2
0
0
1
2
3
4
5
6
7
8
9
10
0
3
4
5
6
7
8
9
10
0
1
2
0
6
8
10 12 14 16 18 20
2
4
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
1963A G11
1963A G42
1963A G12
LT1963A-1.8 GND Pin Current
LT1963A-3.3 GND Pin Current
LT1963A-2.5 GND Pin Current
25
20
15
10
5
25
20
15
10
5
25
20
15
10
5
T = 25°C
J
T = 25°C
J
T = 25°C
J
V
= V
IN
V
= V
V
= V
SHDN
SHDN
IN
SHDN
IN
*FOR V
= 1.8V
*FOR V
= 3.3V
*FOR V
= 2.5V
OUT
OUT
OUT
R
L
= 8.33, I = 300mA*
L
R
L
= 11, I = 300mA*
L
R
L
= 6, I = 300mA*
L
R
L
= 25, I = 100mA*
L
R
L
= 33, I = 100mA*
L
R
L
= 18, I = 100mA*
L
R
2
= 180, I = 10mA*
L
L
R
= 250, I = 10mA*
R
= 330, I = 100mA*
L L
L
L
0
0
0
0
1
2
3
4
5
6
7
8
9
10
0
1
3
4
5
6
7
8
9 10
0
1
2
3
4
5
6
7
8
9 10
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
1963A G15
1963A G13
1963A G14
1963aff
8
For more information www.linear.com/LT1963A
LT1963A Series
Typical perForMance characTerisTics
LT1963A GND Pin Current
LT1963A-1.5 GND Pin Current
LT1963A-1.8 GND Pin Current
100
90
80
70
60
50
40
30
20
10
0
10
8
100
90
80
70
60
50
40
30
20
10
0
T = 25°C
J
T = 25°C
J
T = 25°C
J
V
= V
IN
V
= V
IN
OUT
SHDN
V
= V
SHDN
SHDN
IN
*FOR V
= 1.5V
*FOR V
= 1.8V
*FOR V
= 1.21V
OUT
OUT
R
= 4.33, I = 300mA*
L
L
R
= 1.2, I = 1.5A*
L
6
L
R
L
= 1, I = 1.5A*
L
R
= 1.5, I = 1A*
L
L
4
R
L
= 1.8, I = 1A*
L
R
L
= 12.1, I = 100mA*
L
R
L
= 3, I = 500mA*
L
2
R
L
= 3.6, I = 500mA*
L
R
L
= 121, I = 10mA*
L
0
4
0
1
2
3
5
6
7
8
9
10
0
1
2
3
4
5
6
7
8
9 10
0
1
2
3
4
5
6
7
8
9
10
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
1963A G17
1963A G16
1963A G43
LT1963A-2.5 GND Pin Current
LT1963A GND Pin Current
LT1963A-3.3 GND Pin Current
100
90
80
70
60
50
40
30
20
10
0
100
90
80
70
60
50
40
30
20
10
0
100
90
80
70
60
50
40
30
20
10
0
T = 25°C
J
T = 25°C
J
T = 25°C
J
V
= V
IN
V
= V
SHDN
V
= V
IN
SHDN
IN
SHDN
*FOR V
= 3.3V
*FOR V
= 1.21V
OUT
*FOR V
= 2.5V
OUT
OUT
R
L
= 2.2, I = 1.5A*
L
R
L
= 1.67, I = 1.5A*
L
R
L
= 0.81, I = 1.5A*
L
R
L
= 2.5, I = 1A*
L
R
L
= 3.3, I = 1A*
L
R
L
= 1.21, I = 1A*
L
R
L
= 5, I = 500mA*
L
R
L
= 6.6, I = 500mA*
L
R
L
= 2.42, I = 500mA*
L
4
0
1
2
3
4
6
7
8
9
10
4
0
1
2
3
5
6
7
8
9
10
5
0
1
2
3
6
7
8
9
10
5
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
1963A G18
1963A G19
1963A G20
GND Pin Current vs ILOAD
SHDN Pin Threshold (Off-to-On)
SHDN Pin Threshold (On-to-Off)
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
100
90
80
70
60
50
40
30
20
10
0
I
= 1mA
V
IN
= V
+1V
L
OUT (NOMINAL)
I
= 1.5A
L
I
= 1mA
L
–50
0
25
50
75 100 125
–50
0
25
50
75 100 125
–25
–25
0.8
OUTPUT CURRENT (A)
0
0.2 0.4 0.6
1.0 1.2 1.4 1.6
TEMPERATURE (°C)
TEMPERATURE (°C)
1963A G22
1963A G23
1963A G21
1963aff
9
For more information www.linear.com/LT1963A
LT1963A Series
Typical perForMance characTerisTics
SHDN Pin Input Current
SHDN Pin Input Current
ADJ Pin Bias Current
7
6
5
4
3
2
1
0
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
V
SHDN
= 20V
–50 –25
0
25
50
75
100 125
0
2
4
6
10 12 14 16 18 20
–50
–25
0
25
50
75 100 125
8
TEMPERATURE (°C)
TEMPERATURE (°C)
SHDN PIN VOLTAGE (V)
1963A G25
1963A G24
1963A G26
Current Limit
Current Limit
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
3.0
2.5
2.0
1.5
1.0
0.5
0
V
V
= 7V
IN
OUT
= 0V
T = 25°C
J
T = –50°C
J
T = 125°C
J
ΔV
OUT
= 100mV
–50
0
25
50
75 100 125
–25
0
2
4
6
8
10 12 14 16 18 20
TEMPERATURE (°C)
INPUT/OUTPUT DIFFERENTIAL (V)
1963A G28
1963A G27
Reverse Output Current
Reverse Output Current
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
V
V
V
V
V
V
= 0V
IN
= 1.21V (LT1963A)
OUT
OUT
OUT
OUT
OUT
LT1963A-1.8
LT1963A-1.5
= 1.5V (LT1963A-1.5)
= 1.8V (LT1963A-1.8)
= 2.5V (LT1963A-2.5)
= 3.3V (LT1963A-3.3)
LT1963A
LT1963A-1.8/-2.5/-3.3
LT1963A-3.3
T = 25°C
IN
CURRENT FLOWS INTO
OUTPUT PIN
J
V
LT1963A
= 0V
LT1963A-2.5
V
OUT
V
OUT
= V
(LT1963A)
ADJ
FB
= V (LT1963A-1.5/1.8/-2.5/-3.3)
4
50
TEMPERATURE (°C)
125
0
1
2
3
5
6
7
8
9
10
–50
0
25
75 100
–25
OUTPUT VOLTAGE (V)
1963A G29
1963A G30
1963aff
10
For more information www.linear.com/LT1963A
LT1963A Series
Typical perForMance characTerisTics
Ripple Rejection
Ripple Rejection
LT1963A Minimum Input Voltage
80
70
60
50
40
30
20
10
0
76
74
72
70
68
66
64
62
3.0
2.5
2.0
1.5
1.0
0.5
0
I
= 1.5A
L
I
= 500mA
L
I
L
= 100mA
C
OUT
= 100µF TANTALUM
+10 × 1µF CERAMIC
C
= 10µF TANTALUM
OUT
I
= 0.75A
L
I
= 0.75A
L
V
= V
+1V + 0.5V
IN
OUT(NOMINAL) P-P
V
= V
+1V + 50mV
10k
RIPPLE
RMS
IN
OUT(NOMINAL)
RIPPLE AT f = 120Hz
–50 –25 25
TEMPERATURE (°C)
10
100
1k
100k
1M
50
75
100 125
50
TEMPERATURE (°C)
100 125
0
–50
–25
0
25
75
FREQUENCY (Hz)
1963A G31
1963A G32
1963A G33
Load Regulation
Output Noise Spectral Density
10
1.0
0.1
C
L
= 10µF
OUT
I
=1.5A
5
0
LT1963A-1.5
LT1963A
LT1963A-2.5
LT1963A-1.8
LT1963A-3.3
–5
LT1963A-2.5
LT1963A-3.3
–10
–15
–20
LT1963A
V
V
= V
+1V
IN
OUT(NOMINAL)
LT1963A-1.8
LT1963A-1.5
(LT1963A-1.8/-2.5/-3.3)
= 2.7V (LT1963A/LT1963A-1.5)
IN
L
ΔI = 1mA TO 1.5A
0.01
50
100 125
–50 –25
0
25
75
10
100
1k
10k
100k
FREQUENCY (Hz)
TEMPERATURE (°C)
1963A G35
1963A G34
RMS Output Noise vs Load
Current (10Hz to 100kHz)
LT1963A-3.3 10Hz to 100kHz Output Noise
50
C
OUT
= 10µF
45
40
35
30
25
20
15
10
5
LT1963A-3.3
LT1963A-2.5
LT1963A-1.8
V
OUT
100µV/DIV
LT1963A-1.5
LT1963A
0
1963A G37
C
LOAD
= 10µF
= 1.5A
0.0001 0.001
0.01
0.1
1
10
1ms/DIV
OUT
I
LOAD CURRENT (A)
1963A G36
1963aff
11
For more information www.linear.com/LT1963A
LT1963A Series
Typical perForMance characTerisTics
LT1963A-3.3 Transient Response
LT1963A-3.3 Transient Response
200
150
100
50
V
C
C
= 4.3V
IN
IN
= 3.3µF TANTALUM
150
100
50
= 10µF TANTALUM
OUT
0
0
–50
–100
–150
1.5
1.0
0.5
0
–50
–100
0.6
0.4
0.2
0
V
C
C
= 4.3V
IN
IN
= 33µF TANTALUM
= 100µF TANTALUM
OUT
+10 × 1µF CERAMIC
8
0
2
4
6
10 12 14 16 18 20
250
300 350 400 450 500
0
50 100 150 200
TIME (µs)
TIME (µs)
1963A G38
1963A G39
1963aff
12
For more information www.linear.com/LT1963A
LT1963A Series
pin FuncTions
OUT: Output. The output supplies power to the load.
A minimum output capacitor of 10µF is required to
prevent oscillations. Larger output capacitors will be
required for applications with large transient loads to limit
peak voltage transients. See the Applications Information
section for more information on output capacitance and
reverse output characteristics.
be off when the SHDN pin is pulled low. The SHDN pin can
be driven either by 5V logic or open-collector logic with a
pull-up resistor. The pull-up resistor is required to supply
the pull-up current of the open-collector gate, normally
severalmicroamperes,andtheSHDNpincurrent,typically
3µA. If unused, the SHDN pin must be connected to V .
IN
The device will be in the low power shutdown state if the
SHDN pin is not connected.
SENSE: Sense. For fixed voltage versions of the LT1963A
(LT1963A-1.5/LT1963A-1.8/LT1963A-2.5/LT1963A-3.3),
the SENSE pin is the input to the error amplifier. Optimum
regulation will be obtained at the point where the SENSE
pin is connected to the OUT pin of the regulator. In criti-
cal applications, small voltage drops are caused by the
IN: Input. Power is supplied to the device through the IN
pin. A bypass capacitor is required on this pin if the device
is more than six inches away from the main input filter
capacitor. In general, the output impedance of a battery
rises with frequency, so it is advisable to include a bypass
capacitor in battery-powered circuits. A bypass capacitor
in the range of 1µF to 10µF is sufficient. The LT1963A
regulators are designed to withstand reverse voltages
on the IN pin with respect to ground and the OUT pin. In
the case of a reverse input, which can happen if a battery
is plugged in backwards, the device will act as if there is
a diode in series with its input. There will be no reverse
current flow into the regulator and no reverse voltage
will appear at the load. The device will protect both itself
and the load.
resistance (R ) of PC traces between the regulator and the
P
load. These may be eliminated by connecting the SENSE
pin to the output at the load as shown in Figure 1 (Kelvin
Sense Connection). Note that the voltage drop across
the external PC traces will add to the dropout voltage of
the regulator. The SENSE pin bias current is 600µA at
the nominal rated output voltage. The SENSE pin can be
pulled below ground (as in a dual supply system where
the regulator load is returned to a negative supply) and
still allow the device to start and operate.
ADJ: Adjust. For the adjustable LT1963A, this is the input
to the error amplifier. This pin is internally clamped to ±±V.
It has a bias current of 3µA which flows into the pin. The
ADJ pin voltage is 1.21V referenced to ground and the
output voltage range is 1.21V to 20V.
IN
OUT
LT1963A
R
P
+
+
SHDN SENSE
LOAD
V
IN
GND
R
P
1963A F01
SHDN:Shutdown.TheSHDNpinisusedtoputtheLT1963A
regulatorsintoalowpowershutdownstate.Theoutputwill
Figure 1. Kelvin Sense Connection
1963aff
13
For more information www.linear.com/LT1963A
LT1963A Series
applicaTions inForMaTion
The LT1963A series are 1.5A low dropout regulators opti-
mized for fast transient response. The devices are capable
of supplying 1.5A at a dropout voltage of 350mV. The low
operating quiescent current (1mA) drops to less than 1µA
in shutdown. In addition to the low quiescent current, the
LT1963Aregulatorsincorporateseveralprotectionfeatures
whichmakethemidealforuseinbattery-poweredsystems.
The devices are protected against both reverse input and
reverse output voltages. In battery backup applications
where the output can be held up by a backup battery when
the input is pulled to ground, the LT1963A-X acts like it
has a diode in series with its output and prevents reverse
current flow. Additionally, in dual supply applications
where the regulator load is returned to a negative supply,
the output can be pulled below ground by as much as 20V
and still allow the device to start and operate.
IN
OUT
V
OUT
+
V
IN
R2
R1
LT1963A
ADJ
R2
VOUT =1.21V 1+
+ I
(
R2
ADJ)( )
R1
GND
V
ADJ =1.21V
ADJ =3µA AT 25°C
OUTPUT RANGE = 1.21V TO 20V
I
1963A F02
Figure 2. Adjustable Operation
makeitstable. FortheLT1963A, thefrequencycompensa-
tion is both internal and external—the output capacitor.
The size of the output capacitor, the type of the output
capacitor, and the ESR of the particular output capacitor
all affect the stability.
In addition to stability, the output capacitor also affects
the high frequency transient response. The regulator
loop has a finite band width. For high frequency transient
loads, recovery from a transient is a combination of the
output capacitor and the bandwidth of the regulator. The
LT1963A was designed to be easy to use and accept a
wide variety of output capacitors. However, the frequency
compensationisaffectedbytheoutputcapacitorandopti-
mumfrequencystabilitymayrequiresomeESR,especially
with ceramic capacitors.
Adjustable Operation
The adjustable version of the LT1963A has an output
voltage range of 1.21V to 20V. The output voltage is set
by the ratio of two external resistors as shown in Figure
2. The device servos the output to maintain the voltage at
the ADJ pin at 1.21V referenced to ground. The current
in R1 is then equal to 1.21V/R1 and the current in R2 is
the current in R1 plus the ADJ pin bias current. The ADJ
pin bias current, 3µA at 25°C, flows through R2 into the
ADJ pin. The output voltage can be calculated using the
formula in Figure 2. The value of R1 should be less than
4.1±k to minimize errors in the output voltage caused by
the ADJ pin bias current. Note that in shutdown the output
is turned off and the divider current will be zero.
Foreaseofuse,lowESRpolytantalumcapacitors(POSCAP)
are a good choice for both the transient response and
stability of the regulator. These capacitors have intrinsic
ESR that improves the stability. Ceramic capacitors have
extremely low ESR, and while they are a good choice in
many cases, placing a small series resistance element
will sometimes achieve optimum stability and minimize
ringing. In all cases, a minimum of 10µF is required while
the maximum ESR allowable is 3Ω.
The adjustable device is tested and specified with the ADJ
pin tied to the OUT pin for an output voltage of 1.21V.
Specifications for output voltages greater than 1.21V will
be proportional to the ratio of the desired output voltage
The place where ESR is most helpful with ceramics is
low output voltage. At low output voltages, below 2.5V,
someESRhelpsthestabilitywhenceramicoutputcapaci-
tors are used. Also, some ESR allows a smaller capaci-
tor value to be used. When small signal ringing occurs
with ceramics due to insufficient ESR, adding ESR or
increasing the capacitor value improves the stability and
reduces the ringing. Table 1 gives some recommended
values of ESR to minimize ringing caused by fast, hard
current transitions.
to 1.21V: V /1.21V. For example, load regulation for an
OUT
output current change of 1mA to 1.5A is –3mV typical at
V
= 1.21V. At V
= 5V, load regulation is:
OUT
OUT
(5V/1.21V)(–3mV) = –12.4mV
Output Capacitors and Stability
The LT1963A regulator is a feedback circuit. Like any
feedback circuit, frequency compensation is needed to
1963aff
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Table 1. Capacitor Minimum ESR
POSCAP capacitors are used. The output voltage is at the
worst case value of 1.2V. Trace A, is with a 10µF ceramic
outputcapacitorandshowssignificantringingwithapeak
amplitude of 25mV. For Trace B, a 22µF/45mΩ POSCAP
is added in parallel with the 10µF ceramic. The output is
well damped and settles to within 10mV in less than 20µs.
V
10µF
20mΩ
20mΩ
15mΩ
5mΩ
22µF
15mΩ
15mΩ
10mΩ
5mΩ
47µF
10mΩ
10mΩ
10mΩ
5mΩ
100µF
5mΩ
5mΩ
5mΩ
5mΩ
5mΩ
0mΩ
OUT
1.2V
1.5V
1.8V
2.5V
3.3V
≥5V
0mΩ
0mΩ
0mΩ
ForTraceC,a100µF/35mΩPOSCAPisconnectedinparallel
withthe10µFceramiccapacitor.Inthiscasethepeakoutput
deviation is less than 20mV and the output settles in about
10µs. For improved transient response the value of the
bulk capacitor (tantalum or aluminum electrolytic) should
be greater than twice the value of the ceramic capacitor.
0mΩ
0mΩ
0mΩ
Figures3through8showtheeffectofESRonthetransient
response of the regulator. These scope photos show the
transientresponsefortheLT1963Aatthreedifferentoutput
voltageswithvariouscapacitorsandvariousvaluesofESR.
The output load conditions are the same for all traces. In
all cases there is a DC load of 500mA. The load steps up
to 1A at the first transition and steps back to 500mA at
the second transition.
Tantalum and Polytantalum Capacitors
There is a variety of tantalum capacitor types available,
with a wide range of ESR specifications. Older types have
ESRspecificationsinthehundredsofmΩtoseveralOhms.
Some newer types of polytantalum with multi-electrodes
havemaximumESRspecificationsaslowas5mΩ. Ingen-
eral the lower the ESR specification, the larger the size and
the higher the price. Polytantalum capacitors have better
surge capability than older types and generally lower ESR.
Some types such as the Sanyo TPE and TPB series have
ESR specifications in the 20mΩ to 50mΩ range, which
provide near optimum transient response.
At the worst case point of 1.2V
with 10µF C
OUT
OUT
(Figure 3), a minimum amount of ESR is required. While
20mΩ is enough to eliminate most of the ringing, a value
closer to 50mΩ provides a more optimum response. At
2.5V output with 10µF C
(Figure 4) the output rings
OUT
at the transitions with 0Ω ESR but still settles to within
10mV in 20µs after the 0.5A load step. Once again a small
value of ESR will provide a more optimum response.
At 5V
with 10µF C
(Figure 5) the response is well
OUT
OUT
Aluminum Electrolytic Capacitors
damped with 0Ω ESR.
Aluminumelectrolyticcapacitorscanalsobeusedwiththe
LT1963A.Thesecapacitorscanalsobeusedinconjunction
with ceramic capacitors. These tend to be the cheapest
and lowest performance type of capacitors. Care must be
used in selecting these capacitors as some types can have
ESR which can easily exceed the 3Ω maximum value.
With a C of 100µF at 0Ω ESR and an output of 1.2V
OUT
(Figure 6), the output rings although the amplitude is
only 20mV . With C of 100µF it takes only 5mΩ to
p-p
OUT
20mΩ of ESR to provide good damping at 1.2V output.
Performanceat2.5Vand5Voutputwith100µFC shows
OUT
similar characteristics to the 10µF case (see Figures ±-8).
At2.5V
5mΩto20mΩcanimprovetransientresponse.
OUT
Ceramic Capacitors
At 5V
the response is well damped with 0Ω ESR.
OUT
Extra consideration must be given to the use of ceramic
capacitors. Ceramic capacitors are manufactured with a
variety of dielectrics, each with different behavior over
temperature and applied voltage. The most common
dielectrics used are Z5U, Y5V, X5R and X±R. The Z5U and
CapacitortypeswithinherentlyhigherESRcanbecombined
with 0mΩ ESR ceramic capacitors to achieve both good
high frequency bypassing and fast settling time. Figure
9 illustrates the improvement in transient response that
can be seen when a parallel combination of ceramic and
1963aff
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V
= 1.2V
V
= 1.2V
OUT
OUT
OUT
OUT
I
= 500mA WITH
500mA PULSE
= 10µF
I
= 500mA WITH
500mA PULSE
= 100µF
0
5
0
C
OUT
C
OUT
20
10
20
50
100
1963A F03
1963A F06
20µs/DIV
50µs/DIV
Figure 3
Figure 6
V
= 2.5V
V
= 2.5V
OUT
OUT
OUT
OUT
I
= 500mA WITH
500mA PULSE
= 10µF
I
= 500mA WITH
500mA PULSE
= 100µF
0
0
5
C
C
OUT
OUT
20
50
10
20
100
1963A F04
1963A F07
20µs/DIV
50µs/DIV
Figure 4
Figure 7
V
OUT
= 5V
V
= 5V
OUT
OUT
OUT
I
= 500mA WITH
500mA PULSE
= 10µF
I
= 500mA WITH
500mA PULSE
= 100µF
0
5
0
20
C
C
OUT
OUT
10
20
50
100
1963A F05
1963A F08
20µs/DIV
50µs/DIV
Figure 8
Figure 5
V
= 1.2V
OUT
OUT
I
= 500mA WITH 500mA PULSE
=
A
C
OUT
A = 10µF CERAMIC
B = 10µF CERAMIC II 22µF/45mΩ POLY
C = 10µF CERAMIC II 100µF/35mΩ POLY
B
C
1963A F09
50µs/DIV
Figure 9
1963aff
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Y5Vdielectricsaregoodforprovidinghighcapacitancesin
asmallpackage,butexhibitstrongvoltageandtemperature
coefficients as shown in Figures 10 and 11. When used
with a 5V regulator, a 10µF Y5V capacitor can exhibit an
effective value as low as 1µF to 2µF over the operating
temperature range. The X5R and X7R dielectrics result in
more stable characteristics and are more suitable for use
as the output capacitor. The X7R type has better stability
across temperature, while the X5R is less expensive and
is available in higher values.
“FREE” Resistance with PC Traces
The resistance values shown in Table 2 can easily be made
using a small section of PC trace in series with the output
capacitor. The wide range of non-critical ESR makes it
easy to use PC trace. The trace width should be sized to
handle the RMS ripple current associated with the load.
Theoutputcapacitoronlysourcesorsinkscurrentforafew
microsecondsduringfastoutputcurrenttransitions.There
is no DC current in the output capacitor. Worst case ripple
current will occur if the output load is a high frequency
(>100kHz) square wave with a high peak value and fast
edges (< 1µs). Measured RMS value for this case is 0.5
times the peak-to-peak current change. Slower edges or
lower frequency will significantly reduce the RMS ripple
current in the capacitor.
Voltage and temperature coefficients are not the only
sources of problems. Some ceramic capacitors have a
piezoelectric response. A piezoelectric device generates
voltage across its terminals due to mechanical stress,
similar to the way a piezoelectric accelerometer or micro-
phone works. For a ceramic capacitor the stress can be
induced by vibrations in the system or thermal transients.
Table 2. PC Trace Resistors
10mΩ
20mΩ
30mΩ
"
"
"
0.5oz C
1.0oz C
2.0oz C
Width
0.011 (0.28mm)
0.011 (0.28mm)
0.011 (0.28mm)
U
U
U
"
"
"
Length
0.102 (2.6mm)
0.204 (5.2mm)
0.307 (7.8mm)
"
"
"
Width
Length
0.006 (0.15mm)
0.006 (0.15mm)
0.006 (0.15mm)
"
"
"
0.110 (2.8mm)
0.220 (5.6mm)
0.330 (8.4mm)
"
"
"
"
Width
Length
0.006 (0.15mm)
0.006 (0.15mm)
0.006 (0.15mm)
"
"
0.224 (5.7mm)
0.450 (11.4mm)
0.670 (17mm)
40
20
20
0
BOTH CAPACITORS ARE 16V,
1210 CASE SIZE, 10µF
X5R
X5R
0
–20
–40
–60
–80
–100
–20
–40
–60
–80
–100
Y5V
Y5V
BOTH CAPACITORS ARE 16V,
1210 CASE SIZE, 10µF
0
8
12 14
50
TEMPERATURE (°C)
100 125
2
4
6
10
16
–50 –25
0
25
75
DC BIAS VOLTAGE (V)
1963A F10
1963A F11
Figure 11. Ceramic Capacitor Temperature Characteristics
Figure 10. Ceramic Capacitor DC Bias Characteristics
1963aff
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This resistor should be made using one of the inner
layers of the PC board which are well defined. The resistiv-
ity is determined primarily by the sheet resistance of the
copper laminate with no additional plating steps. Table
2 gives some sizes for 0.75A RMS current for various
copper thicknesses. More detailed information regarding
resistors made from PC traces can be found in Application
Note 69, Appendix A.
typically 40nV/√Hz over this frequency bandwidth for
the LT1963A (adjustable version). For higher output
voltages (generated by using a resistor divider), the
output voltage noise will be gained up accordingly. This
results in RMS noise over the 10Hz to 100kHz bandwidth
of 14µV
for the LT1963A increasing to 38µV
for
RMS
RMS
the LT1963A-3.3.
Higher values of output voltage noise may be measured
when care is not exercised with regard to circuit layout
and testing. Crosstalk from nearby traces can induce
unwanted noise onto the output of the LT1963A-X.
Powersupplyripplerejectionmustalsobeconsidered;the
LT1963A regulators do not have unlimited power supply
rejection and will pass a small portion of the input noise
through to the output.
Overload Recovery
LikemanyICpowerregulators,theLT1963A-Xhassafeop-
eratingareaprotection.Thesafeareaprotectiondecreases
the current limit as input-to-output voltage increases and
keeps the power transistor inside a safe operating region
for all values of input-to-output voltage. The protection
is designed to provide some output current at all values
of input-to-output voltage up to the device breakdown.
Thermal Considerations
Thepowerhandlingcapabilityofthedeviceislimitedbythe
maximum rated junction temperature (125°C). The power
dissipated by the device is made up of two components:
When power is first turned on, as the input voltage rises,
the output follows the input, allowing the regulator to start
up into very heavy loads. During the start-up, as the input
voltage is rising, the input-to-output voltage differential
is small, allowing the regulator to supply large output
currents. With a high input voltage, a problem can occur
wherein removal of an output short will not allow the
output voltage to recover. Other regulators, such as the
LT1085, also exhibit this phenomenon, so it is not unique
to the LT1963A-X.
1. Output current multiplied by the input/output voltage
differential: (I )(V – V ), and
OUT
IN
OUT
2. GND pin current multiplied by the input voltage: (I
)
GND
(V ).
IN
The GND pin current can be found using the GND Pin
CurrentcurvesintheTypicalPerformanceCharacteristics.
Power dissipation will be equal to the sum of the two
components listed above.
The problem occurs with a heavy output load when the
inputvoltageishighandtheoutputvoltageislow.Common
situations are immediately after the removal of a short-
circuit or when the shutdown pin is pulled high after the
input voltage has already been turned on. The load line for
such a load may intersect the output current curve at two
points. If this happens, there are two stable output operat-
ing points for the regulator. With this double intersection,
the input power supply may need to be cycled down to
zero and brought up again to make the output recover.
The LT1963A series regulators have internal thermal
limiting designed to protect the device during overload
conditions. For continuous normal conditions, the maxi-
mum 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 ambi-
ent. Additional heat sources mounted nearby must also
be considered.
For surface mount devices, heat sinking is accomplished
by using the heat spreading capabilities of the PC board
and its copper traces. Copper board stiffeners and plated
through-holes can also be used to spread the heat gener-
ated by power devices.
Output Voltage Noise
The LT1963A regulators have been designed to provide
low output voltage noise over the 10Hz to 100kHz band-
width while operating at full load. Output voltage noise is
1963aff
18
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The following tables list thermal resistance for several The power dissipated by the device will be equal to:
different board sizes and copper areas. All measurements
I
(V
– V ) + I (V
)
OUT(MAX) IN(MAX)
OUT
GND IN(MAX)
were taken in still air on 1/16" FR-4 board with one ounce
copper.
where,
I
= 500mA
= 6V
OUT
OUT(MAX)
Table 3. Q Package, 5-Lead DD
V
IN(MAX)
COPPER AREA
THERMAL RESISTANCE
I
at (I
= 500mA, V = 6V) = 10mA
TOPSIDE* BACKSIDE BOARD AREA (JUNCTION-TO-AMBIENT)
GND
IN
2
2
2
2
2
2
2
2
So,
2500mm
1000mm
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
23°C/W
25°C/W
33°C/W
P = 500mA(6V – 3.3V) + 10mA(6V) = 1.41W
2
125mm
Using a DD package, the thermal resistance will be in the
range of 23°C/W to 33°C/W depending on the copper
area. So the junction temperature rise above ambient will
be approximately equal to:
*Device is mounted on topside
Table 4. S0-8 Package, 8-Lead SO
COPPER AREA
TOPSIDE* BACKSIDE BOARD AREA (JUNCTION-TO-AMBIENT)
THERMAL RESISTANCE
1.41W(28°C/W) = 39.5°C
2
2
2
2
2
2
2
2
2
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
55°C/W
55°C/W
63°C/W
69°C/W
2
The maximum junction temperature will then be equal to
the maximum junction temperature rise above ambient
plus the maximum ambient temperature or:
1000mm
2
225mm
125mm
2
*Device is mounted on topside
T
JMAX
= 50°C + 39.5°C = 89.5°C
Table 5. SOT-223 Package, 3-Lead SOT-223
Protection Features
COPPER AREA
THERMAL RESISTANCE
The LT1963A regulators incorporate several protection
featureswhichmakethemidealforuseinbattery-powered
circuits. In addition to the normal protection features
associated with monolithic regulators, such as current
limiting and thermal limiting, the devices are protected
against reverse input voltages, reverse output voltages
and reverse voltages from output to input.
TOPSIDE* BACKSIDE BOARD AREA (JUNCTION-TO-AMBIENT)
2
2
2
2500mm
1000mm
2500mm
2500mm
2500mm
2500mm
42°C/W
42°C/W
2
2
2
2
2
2
2
2
2
2
2
225mm
100mm
2500mm
2500mm
1000mm
2500mm
2500mm
1000mm
1000mm
50°C/W
56°C/W
49°C/W
52°C/W
2
2
2
1000mm
1000mm
2
0mm
Current limit protection and thermal overload protection
areintendedtoprotectthedeviceagainstcurrentoverload
conditions at the output of the device. For normal opera-
tion, the junction temperature should not exceed 125°C.
*Device is mounted on topside
T Package, 5-Lead TO-220
Thermal Resistance (Junction-to-Case) = 4°C/W
The input of the device will withstand reverse voltages of
20V. Current flow into the device will be limited to less
than 1mA (typically less than 100µA) and no negative
voltage will appear at the output. The device will protect
both itself and the load. This provides protection against
batteries that can be plugged in backward.
Calculating Junction Temperature
Example: Given an output voltage of 3.3V, an input volt-
age range of 4V to 6V, an output current range of 0mA
to 500mA and a maximum ambient temperature of 50°C,
what will the maximum junction temperature be?
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The output of the LT1963A can be pulled below ground
withoutdamagingthedevice.Iftheinputisleftopencircuit
or grounded, the output can be pulled below ground by
20V. For fixed voltage versions, the output will act like a
large resistor, typically 5k or higher, limiting current flow
to typically less than 600µA. For adjustable versions, the
output will act like an open circuit; no current will flow out
of the pin. If the input is powered by a voltage source, the
output will source the short-circuit current of the device
and will protect itself by thermal limiting. In this case,
grounding the SHDN pin will turn off the device and stop
the output from sourcing the short-circuit current.
In circuits where a backup battery is required, several
different input/output conditions can occur. The output
voltage may be held up while the input is either pulled
to ground, pulled to some intermediate voltage, or is left
open circuit. Current flow back into the output will follow
the curve shown in Figure 12.
When the IN pin of the LT1963A is forced below the OUT
pin or the OUT pin is pulled above the IN pin, input cur-
rent will typically drop to less than 2µA. This can happen
if the input of the device is connected to a discharged
(low voltage) battery and the output is held up by either
a backup battery or a second regulator circuit. The state
of the SHDN pin will have no effect on the reverse output
current when the output is pulled above the input.
The ADJ pin of the adjustable device can be pulled above
or below ground by as much as 7V without damaging the
device. Iftheinputisleftopencircuitorgrounded, theADJ
pin will act like an open circuit when pulled below ground
and like a large resistor (typically 5k) in series with a diode
when pulled above ground.
5.0
LT1963A
V
= V
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
OUT
ADJ
LT1963A-1.5
= V
V
OUT
FB
In situations where the ADJ pin is connected to a resistor
dividerthatwouldpulltheADJpinaboveits7Vclampvolt-
age if the output is pulled high, the ADJ pin input current
must be limited to less than 5mA. For example, a resistor
divider is used to provide a regulated 1.5V output from the
1.21V reference when the output is forced to 20V. The top
resistor of the resistor divider must be chosen to limit the
current into the ADJ pin to less than 5mA when the ADJ
pin is at 7V. The 13V difference between OUT and ADJ
pins divided by the 5mA maximum current into the ADJ
pin yields a minimum top resistor value of 2.6k.
LT1963A-1.8
= V
V
OUT
FB
LT1963A-2.5
= V
V
OUT
FB
LT1963A-3.3
= V
V
OUT
FB
T = 25°C
J
IN
V
= 0V
CURRENT FLOWS
INTO OUTPUT PIN
0
1
2
3
4
5
6
7
8
9
10
OUTPUT VOLTAGE (V)
1963A F12
Figure 12. Reverse Output Current
1963aff
20
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LT1963A Series
Typical applicaTions
SCR Pre-Regulator Provides Efficiency Over Line Variations
L1
500µH
LT1963A-3.3
3.3V
1.5A
OUT
IN
OUT
L2
1N4148
1k
+
+
10VAC AT
115V
SHDN
GND
FB
10000µF
22µF
IN
90-140
VAC
34k*
10VAC AT
115V
IN
1N4002
“SYNC”
1N4002
1N4002
12.1k*
+V
2.4k
C1A
TO ALL “+V”
POINTS
200k
+
1N4148
+
1/2
22µF
750Ω
LT1018
0.1µF
–
+V
C1B
+
750Ω
+V
A1
0.033µF
1/2
LT1018
+
–
1N4148
10k
–
LT1006
10k
10k
+V
1µF
+V
L1 = COILTRONICS CTX500-2-52
L2 = STANCOR P-8559
* = 1% FILM RESISTOR
= NTE5437
LT1004
1.2V
1963A TA03
Paralleling of Regulators for Higher Output Current
R1, 0.01Ω
LT1963A-3.3
3.3V
3A
C2
22µF
IN
OUT
+
+
C1
100µF
V
IN
> 3.7V
SHDN
GND
FB
R2
0.01Ω
LT1963A
IN
OUT
R6
6.65k
SHDN
GND
FB
SHDN
R7
4.12k
R3
2.2k
R4
2.2k
R5
1k
3
2
8
+
–
1
1/2
LT1366
C3
0.01µF
4
1963A TA05
1963aff
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LT1963A Series
pacKage DescripTion
Q Package
5-Lead Plastic DD Pak
(Reference LTC DWG # 05-08-1461 Rev F)
.060
(1.524)
TYP
.390 – .415
(9.906 – 10.541)
.060
(1.524)
.165 – .180
(4.191 – 4.572)
.256
(6.502)
.045 – .055
(1.143 – 1.397)
15° TYP
+.008
.004
–.004
.060
(1.524)
.059
(1.499)
TYP
.183
(4.648)
.330 – .370
(8.382 – 9.398)
+0.203
–0.102
0.102
(
)
.095 – .115
(2.413 – 2.921)
.075
(1.905)
DETAIL A
.067
(1.702)
BSC
.050 .012
(1.270 0.305)
.300
(7.620)
.013 – .023
(0.330 – 0.584)
+.012
.143
–.020
.028 – .038
(0.711 – 0.965)
TYP
+0.305
BOTTOM VIEW OF DD PAK
HATCHED AREA IS SOLDER PLATED
COPPER HEAT SINK
3.632
(
)
–0.508
DETAIL A
0° – 7° TYP
0° – 7° TYP
.420
.276
.080
.420
.350
.325
.585
.205
.320
.585
.090
.042
.090
.067
.042
.067
RECOMMENDED SOLDER PAD LAYOUT
NOTE:
1. DIMENSIONS IN INCH/(MILLIMETER)
2. DRAWING NOT TO SCALE
RECOMMENDED SOLDER PAD LAYOUT
FOR THICKER SOLDER PASTE APPLICATIONS
Q(DD5) 0811 REV F
1963aff
22
For more information www.linear.com/LT1963A
LT1963A Series
pacKage DescripTion
S8 Package
8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610)
.189 – .197
(4.801 – 5.004)
.045 .005
NOTE 3
.050 BSC
7
5
8
6
.245
MIN
.160 .005
.150 – .157
(3.810 – 3.988)
NOTE 3
.228 – .244
(5.791 – 6.197)
.030 .005
TYP
1
3
4
2
RECOMMENDED SOLDER PAD LAYOUT
.010 – .020
(0.254 – 0.508)
× 45°
.053 – .069
(1.346 – 1.752)
.004 – .010
(0.101 – 0.254)
.008 – .010
(0.203 – 0.254)
0°– 8° TYP
.016 – .050
(0.406 – 1.270)
.050
(1.270)
BSC
.014 – .019
(0.355 – 0.483)
TYP
NOTE:
INCHES
1. DIMENSIONS IN
(MILLIMETERS)
2. DRAWING NOT TO SCALE
3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)
SO8 0303
1963aff
23
For more information www.linear.com/LT1963A
LT1963A Series
pacKage DescripTion
ST Package
3-Lead Plastic SOT-223
(Reference LTC DWG # 05-08-1630)
.248 – .264
(6.30 – 6.71)
.129 MAX
.114 – .124
(2.90 – 3.15)
.059 MAX
.264 – .287
(6.70 – 7.30)
.248 BSC
.130 – .146
(3.30 – 3.71)
.039 MAX
.059 MAX
.090
BSC
.181 MAX
RECOMMENDED SOLDER PAD LAYOUT
.033 – .041
(0.84 – 1.04)
.0905
(2.30)
BSC
10° – 16°
.010 – .014
10°
MAX
.071
(1.80)
MAX
(0.25 – 0.36)
10° – 16°
.0008 – .0040
(0.0203 – 0.1016)
.024 – .033
(0.60 – 0.84)
.012
(0.31)
MIN
.181
(4.60)
BSC
ST3 (SOT-233) 0502
1963aff
24
For more information www.linear.com/LT1963A
LT1963A Series
pacKage DescripTion
T Package
5-Lead Plastic TO-220 (Standard)
(Reference LTC DWG # 05-08-1421)
.165 – .180
(4.191 – 4.572)
.147 – .155
(3.734 – 3.937)
DIA
.390 – .415
(9.906 – 10.541)
.045 – .055
(1.143 – 1.397)
.230 – .270
(5.842 – 6.858)
.570 – .620
(14.478 – 15.748)
.620
(15.75)
TYP
.460 – .500
(11.684 – 12.700)
.330 – .370
(8.382 – 9.398)
.700 – .728
(17.78 – 18.491)
.095 – .115
(2.413 – 2.921)
SEATING PLANE
.152 – .202
(3.861 – 5.131)
.155 – .195*
(3.937 – 4.953)
.260 – .320
(6.60 – 8.13)
.013 – .023
(0.330 – 0.584)
.067
BSC
.135 – .165
(3.429 – 4.191)
.028 – .038
(0.711 – 0.965)
(1.70)
* MEASURED AT THE SEATING PLANE
T5 (TO-220) 0801
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25
For more information www.linear.com/LT1963A
LT1963A Series
pacKage DescripTion
FE Package
16-Lead Plastic TSSOP (4.4mm)
(Reference LTC DWG # 05-08-1663 Rev J)
Exposed Pad Variation BB
4.70
(.185)
3.58
DETAIL A
4.90 – 5.10*
(.193 – .201)
0.56
(.022)
REF
(.141)
3.58
(.141)
0.53
(.021)
REF
NOTE 5
16 1514 13 12 1110
9
NOTE 5
DETAIL A IS THE PART OF THE
LEAD FRAM FEATURE FOR
REFERENCE ONLY
6.60 ±0.10
2.94 3.05
(.116) (.120)
4.50 ±0.10
DETAIL A
NO MEASUREMENT PUROSE
6.40
(.252)
BSC
SEE NOTE 4
2.94
(.116)
1.05 ±0.10
0.45 ±0.05
0.65 BSC
5
7
8
1
2
3
4
6
RECOMMENDED SOLDER PAD LAYOUT
1.10
(.0433)
MAX
4.30 – 4.50*
(.169 – .177)
0.25
REF
0° – 8°
0.65
(.0256)
BSC
0.09 – 0.20
(.0035 – .0079)
0.50 – 0.75
(.020 – .030)
0.05 – 0.15
(.002 – .006)
FE16 (BB) TSSOP REV J 1012
0.195 – 0.30
(.0077 – .0118)
TYP
NOTE:
1. CONTROLLING DIMENSION: MILLIMETERS
5. BOTTOM EXPOSED PADDLE MAY HAVE METAL PROTRUSION
IN THIS AREA. THIS REGION MUST BE FREE OF ANY EXPOSED
TRACES OR VIAS ON PBC LAYOUT
MILLIMETERS
2. DIMENSIONS ARE IN
(INCHES)
*DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.150mm (.006") PER SIDE
3. DRAWING NOT TO SCALE
4. RECOMMENDED MINIMUM PCB METAL SIZE
FOR EXPOSED PAD ATTACHMENT
1963aff
26
For more information www.linear.com/LT1963A
LT1963A Series
revision hisTory (Revision history begins at Rev E)
REV
DATE
DESCRIPTION
PAGE NUMBER
E
02/11 Updated FE and Q package drawings in Package Description section
09/13 Replaced graphs with correct versions
22, 26
16
F
1963aff
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 representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
27
LT1963A Series
Typical applicaTion
Adjustable Current Source
R5
0.01Ω
LT1963A-1.8
LOAD
IN
OUT
R1
1k
+
C1
10µF
SHDN
GND
FB
V
IN
> 2.7V
LT1004-1.2
R4
R6
R8
100k
R2
80.6k
C3
1µF
2.2k 2.2k
R3
2k
R7
2
3
470Ω
8
4
+
–
1
1/2
LT1366
C2
3.3µF
NOTE: ADJUST R1 FOR
0A TO 1.5A CONSTANT CURRENT
1963A TA04
relaTeD parTs
PART NUMBER
DESCRIPTION
COMMENTS
V : –20V to –4.3V, V
LT1175
500mA, Micropower, Negative LDO
= –3.8V, V = 0.50V, I = 45µA, I 10µA,
OUT(MIN) DO Q SD
IN
DD, SOT-223, PDIP8 Packages
LT1185
LT1761
3A, Negative LDO
V : –35V to –4.2V, V
= –2.40V, V = 0.80V, I = 2.5mA, I <1µA,
IN
OUT(MIN) DO Q SD
TO220-5 Package
100mA, Low Noise Micropower, LDO
V : 1.8V to 20V, V
= 1.22V, V = 0.30V, I = 20µA, I <1µA
IN
OUT(MIN) DO Q SD
ThinSOT™ Package
LT1762
LT1763
150mA, Low Noise Micropower, LDO
500mA, Low Noise Micropower, LDO
V : 1.8V to 20V, V
= 1.22V, V = 0.30V, I = 25µA, I <1µA, MS8 Package
DO Q SD
IN
OUT(MIN)
OUT(MIN)
OUT(MIN)
V : 1.8V to 20V, V
IN
= 1.22V, V = 0.30V, I = 30µA, I <1µA, S8 Package
DO Q SD
LT1764/
LT1764A
3A, Low Noise, Fast Transient Response, V : 2.7V to 20V, V
LDO
= 1.21V, V = 0.34V, I = 1mA, I <1µA,
DO Q SD
IN
DD, TO220 Packages
LTC1844
LT1962
LT1964
LT1965
LT3020
LT3023
LT3024
150mA, Very Low Drop-Out LDO
V : 6.5V to 1.6V, V
= 1.25V, V = 0.08V, I = 40µA, I < 1µA,
DO Q SD
IN
OUT(MIN)
OUT(MIN)
ThinSOT Package
300mA, Low Noise Micropower, LDO
V : 1.8V to 20V, V
IN
= 1.22V, V = 0.27V, I = 30µA, I <1µA, MS8 Package
DO Q SD
200mA, Low Noise Micropower,
Negative LDO
V : –0.9V to –20V, V
= –1.21V, V = 0.34V, I = 30µA, I 3µA,
OUT(MIN) DO Q SD
IN
ThinSOT Package
1.1A, Low Noise, Low Dropout Linear
Regulator
290mV Dropout Voltage, Low Noise: 40µV
stable with ceramic caps, TO-220, DD-Pak, MSOP and 3mm × 3mm DFN Packages
, V : 1.8V to 20V, V : 1.2V to 19.5V,
RMS IN OUT
100mA, Low Voltage V
IN(MIN)
V : 0.9V to 10V, V = 0.20, V = 0.15V, I = 120µA, I <3µA,
LDO,
IN
OUT(MIN)
DO
Q
SD
V
= 0.9V
DFN, MS8 Packages
Dual, 2x 100mA, Low Noise
Micropower, LDO
V : 1.8V to 20V, V
= 1.22V, V = 0.30V, I = 40µA, I <1µA,
DO Q SD
IN
OUT(MIN)
DFN, MS10 Packages
Dual, 100mA/500mA, Low Noise
Micropower, LDO
V : 1.8V to 20V, V
= 1.22V, V = 0.30V, I = 60µA, I <1µA,
DO Q SD
IN
OUT(MIN)
DFN, TSSOP Packages
LT3080/
LT3080-1
1.1A, Parallelable, Low Noise, Low
Dropout Linear Regulator
300mV Dropout Voltage (2-Supply Operation), Low Noise: 40µV
, V : 1.2V to 36V,
RMS IN
V
: 0V to 35.7V, current-based reference with 1-resistor V
set; directly parallelable
OUT
OUT
(no op amp required), stable with ceramic caps, TO-220, SOT-223, MSOP and 3mm ×
3mm DFN Packages; “–1” version has integrated internal ballast resistor
1963aff
LT 0913 REV F • PRINTED IN USA
LinearTechnology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
28
(408)432-1900 FAX: (408) 434-0507 www.linear.com/LT1963A
●
●
LINEAR TECHNOLOGY CORPORATION 2005
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