Page 1
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
500mA, Low Voltage,
Very Low Dropout
Linear Regulator
FEATURES
n
VIN Range: 0.9V to 10V
n
Dropout Voltage: 160mV Typical
n
Output Current: 500mA
n
Adjustable Output (V
n
Fixed Output Voltages: 1.2V, 1.5V, 1.8V
n
Stable with Low ESR, Ceramic Output Capacitors
REF
= V
OUT(MIN)
= 200mV)
(3.3μF Minimum)
n
0.2% Load Regulation from 0mA to 500mA
n
Quiescent Current: 120μA (Typ)
n
3μA Typical Quiescent Current in Shutdown
n
Current Limit Protection
n
Reverse-Battery Protection
n
No Reverse Current
n
Thermal Limiting with Hysteresis
n
16-Pin DFN (5mm × 5mm) and 8-Lead
SO Packages
APPLICATIONS
n
Low Current Regulators
n
Battery-Powered Systems
n
Cellular Phones
n
Pagers
n
Wireless Modems
DESCRIPTION
The LT®3021 is a very low dropout voltage (VLDO™) linear regulator that operates from input supplies down to
0.9V. This device supplies 500mA of output current with
a typical dropout voltage of 160mV. The LT3021 is ideal
for low input voltage to low output voltage applications,
providing comparable electrical effi ciency to that of a
switching regulator.
The LT3021 regulator optimizes stability and transient
response with low ESR, ceramic output capacitors as small
as 3.3μF. Other LT3021 features include 0.05% typical line
regulation and 0.2% typical load regulation. In shutdown,
quiescent current typically drops to 3μA.
Internal protection circuitry includes reverse-battery protection, current limiting, thermal limiting with hysteresis,
and reverse-current protection. The LT3021 is available as
an adjustable output device with an output range down to
the 200mV reference. Three fi xed output voltages, 1.2V,
1.5V and 1.8V, are also available.
The LT3021 regulator is available in the low profi le
(0.75mm) 16-pin (5mm × 5mm) DFN package with exposed pad and the 8-lead SO package.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. VLDO is
a trademark of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
TYPICAL APPLICATION
1.8V to 1.5V, 500mA VLDO Regulator
V
1.8V
IN
3.3μF
IN
LT3021-1.5
SHDN
OUT
SENSE
GND
3021 TA01
3.3μF
V
OUT
1.5V
500mA
Minimum Input Voltage
1.1
IL = 500mA
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
MINIMUM INPUT VOLTAGE (V)
0.2
0.1
0
–50
250–25 50 75
TEMPERATURE (°C)
125100
3021 TA02
3021fc
1
Page 2
LT3021/LT3021-1.2/
(
(
LT3021-1.5/LT3021-1.8
ABSOLUTE MAXIMUM RATINGS
IN Pin Voltage ........................................................ ±10V
OUT Pin Voltage ......................................................±10V
Input-to-Output Differential Voltage ........................±10V
ADJ/SENSE Pin Voltage ....................................... ±10V
SHDN Pin Voltage ................................................. ±10V
Output Short-Circut Duration ......................... Indefi nite
PIN CONFIGURATION
TOP VIEW
NC
1
NC
2
OUT
3
OUT
4
NC
5
NC
6
ADJ
7
AGND
8
16-LEAD
T
= 125°C, θJA = 35°C/ W*, θJC = 3°C/W**
JMAX
EXPOSED PAD IS GND (PIN 17) CONNECT TO PINS 8, 10
EXPOSED PAD MUST BE SOLDERED TO THE PCB
*SEE THE APPLICATIONS INFORMATION SECTION
**MEASURED JUNCTION TO PIN 17
17
LT3021-ADJ
DH PACKAGE
5mm × 5mm) PLASTIC DFN
NC
16
NC
15
IN
14
NC
13
IN
12
NC
11
PGND
10
SHDN
9
(Note 1)
Operating Junction Temperature Range (E, I Grade)
(Notes 2, 3) ............................................– 40°C to 125°C
Storage Temperature Range
DH .....................................................– 65°C to 125°C
S8 ......................................................–65°C to 150°C
Lead Temperature (Soldering, 10 sec, S8) ............ 300°C
TOP VIEW
NC
1
NC
2
OUT
3
OUT
4
NC
5
NC
6
SENSE
7
AGND
8
16-LEAD
T
= 125°C, θJA = 35°C/ W*, θJC = 3°C/W**
JMAX
EXPOSED PAD IS GND (PIN 17) CONNECT TO PINS 8, 10
EXPOSED PAD MUST BE SOLDERED TO THE PCB
*SEE THE APPLICATIONS INFORMATION SECTION
**MEASURED JUNCTION TO PIN 17
17
LT3021-FIXED
DH PACKAGE
5mm × 5mm) PLASTIC DFN
NC
16
NC
15
IN
14
NC
13
IN
12
NC
11
PGND
10
SHDN
9
TOP VIEW
NC
1
OUT
2
ADJ
3
AGND
4
LT3021-ADJ
S8 PACKAGE
T
JMAX
*SEE THE APPLICATIONS INFORMATION SECTION
8-LEAD PLASTIC SO
= 150°C, θJA = 125°C/ W*, θJC = 40°C/W**
**MEASURED JUNCTION TO PIN 6
IN
8
NC
7
PGND
6
SHDN
5
TOP VIEW
NC
1
OUT
2
SENSE
3
AGND
4
LT3021-FIXED
S8 PACKAGE
T
JMAX
*SEE THE APPLICATIONS INFORMATION SECTION
8-LEAD PLASTIC SO
= 150°C, θJA = 125°C/ W*, θJC = 40°C/W**
**MEASURED JUNCTION TO PIN 6
IN
8
NC
7
PGND
6
SHDN
5
3021fc
2
Page 3
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
ORDER INFORMAITON
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LT3021EDH#PBF LT3021EDH#TRPBF 3021
LT3021EDH-1.2#PBF LT3021EDH-1.2#TRPBF 302112
LT3021EDH-1.5#PBF LT3021EDH-1.5#TRPBF 302115
LT3021EDH-1.8#PBF LT3021EDH-1.8#TRPBF 302118
LT3021ES8#PBF LT3021ES8#TRPBF 3021 8-Lead Plastic SO –40°C to 125°C
LT3021ES8-1.2#PBF LT3021ES8-1.2#TRPBF 302112 8-Lead Plastic SO –40°C to 125°C
LT3021ES8-1.5#PBF LT3021ES8-1.5#TRPBF 302115 8-Lead Plastic SO –40°C to 125°C
LT3021ES8-1.8#PBF LT3021ES8-1.8#TRPBF 302118 8-Lead Plastic SO –40°C to 125°C
LT3021IS8-1.8#PBF LT3021IS8-1.8#TRPBF 302118 8-Lead Plastic SO –40°C to 125°C
LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LT3021EDH LT3021EDH#TR 3021
LT3021EDH-1.2 LT3021EDH-1.2#TR 302112
LT3021EDH-1.5 LT3021EDH-1.5#TR 302115
LT3021EDH-1.8 LT3021EDH-1.8#TR 302118
LT3021ES8 LT3021ES8#TR 3021 8-Lead Plastic SO –40°C to 125°C
LT3021ES8-1.2 LT3021ES8-1.2#TR 302112 8-Lead Plastic SO –40°C to 125°C
LT3021ES8-1.5 LT3021ES8-1.5#TR 302115 8-Lead Plastic SO –40°C to 125°C
LT3021ES8-1.8 LT3021ES8-1.8#TR 302118 8-Lead Plastic SO –40°C to 125°C
LT3021IS8-1.8 LT3021IS8-1.8#TR 302118 8-Lead Plastic SO –40°C to 125°C
Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi ed 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 specifi
cations, go to: http://www.linear.com/tapeandreel/
16-Lead (5mm × 5mm) Plastic DFN
16-Lead (5mm × 5mm) Plastic DFN
16-Lead (5mm × 5mm) Plastic DFN
16-Lead (5mm × 5mm) Plastic DFN
16-Lead (5mm × 5mm) Plastic DFN
16-Lead (5mm × 5mm) Plastic DFN
16-Lead (5mm × 5mm) Plastic DFN
16-Lead (5mm × 5mm) Plastic DFN
–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
3021fc
3
Page 4
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
ELECTRICAL CHARACTERISTICS
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
SYMBOL CONDITIONS MIN TYP MAX UNITS
Minimum Input Voltage
(Notes 5,14)
ADJ Pin Voltage (Notes 4, 5) V
Regulated Output Voltage
(Note 4)
Line Regulation (Note 6) LT3021 ΔV
Load Regulation (Note 6) LT3021 V
Dropout Voltage (Notes 7, 12) I
GND Pin Current
V
IN
= V
OUT(NOMINAL)
+ 0.4V
(Notes 8, 12)
Output Voltage Noise C
ADJ Pin Bias Current V
Shutdown Threshold V
SHDN Pin Current (Note 10) V
Quiescent Current in Shutdown V
Ripple Rejection (Note 6) LT3021 V
Current Limit (Note 12) V
Input Reverse Leakage Current V
Reverse Output Current
(Notes 11, 13)
= 500mA, TJ > 0°C
I
LOAD
I
= 500mA, TJ < 0°C
LOAD
= 1.5V, I
IN
1.15V < V
LOAD
< 10V, 1mA < I
IN
LT3021-1.2 V
1.5V < V
LT3021-1.5 V
1.8V < V
LT3021-1.8 V
2.1V < V
LT3021-1.2 ΔV
LT3021-1.5 ΔV
LT3021-1.8 ΔV
LT3021-1.2 V
LT3021-1.5 V
LT3021-1.8 V
= 10mA
LOAD
I
= 10mA
LOAD
I
= 500mA
LOAD
I
= 500mA l
LOAD
= 0mA
I
LOAD
I
= 10mA
LOAD
I
= 100mA
LOAD
I
= 500mA
LOAD
= 4.7μF, I
OUT
ADJ
OUT
V
OUT
SHDN
V
SHDN
IN
= 0.2V, V
= 6V, V
LOAD
IN
= Off to On
= On to Off
= 0V, V
IN
= 10V, V
SHDN
I
LT3021-1.2 V
I
LT3021-1.5 V
I
LT3021-1.8 V
I
= 10V, V
IN
V
IN
IN
OUT
= V
OUT(NOMINAL)
= –10V, V
OUT
LT3021 V
LT3021-1.2 V
LT3021-1.5 V
LT3021-1.8 V
= 25°C.
J
= 1mA
= 1.5V, I
IN
IN
IN
IN
IN
IN
IN
IN
IN
IN
IN
LOAD
< 10V, 1mA < I
IN
= 1.8V, I
LOAD
< 10V, 1mA < I
IN
= 2.1V, I
LOAD
< 10V, 1mA < I
IN
= 1.15V to 10V, I
= 1.5V to 10V, I
= 1.8V to 10V, I
= 2.1V to 10V, I
= 1.15V, ΔI
= 1.5V, ΔI
= 1.8V, ΔI
= 2.1V, ΔI
< 500mA l
LOAD
= 1mA
< 500mA
LOAD
= 1mA
< 500mA
LOAD
= 1mA
< 500mA
LOAD
= 1mA
LOAD
= 1mA
LOAD
= 1mA
LOAD
= 1mA
LOAD
= 1mA to 500mA
LOAD
= 1mA to 500mA
LOAD
= 1mA to 500mA
LOAD
= 1mA to 500mA
LOAD
0.9
0.9
196
193
1.176
l
1.157
1.470
l
1.447
1.764
l
1.737
l
–1.75
l
–10.5
l
–13
l
–15.8
–2
–6
–7.5
–9
200
200
1.200
1.200
1.500
1.500
1.800
1.800
0
0
0
0
0.4
1
1.5
2
1.05
1.10
204
206
1.224
1.236
1.530
1.545
1.836
1.854
+1.75
10.5
13
15.8
2
6
7.5
9
45 75
l
110
155 190
285
l
110
250
920
2.25
= 500mA, BW = 10Hz to 100kHz, V
l
= 1.2V 300 μV
OUT
6.20
10
RMS
= 1.2V (Notes 6, 9) 20 50 nA
= 10V
= 10V
IN
l
l
0.25
l
l
0.61
0.61
3
0.9 V
±1
9.5
= 0V 3 9 μA
– V
IN
LOAD
– V
IN
LOAD
– V
IN
LOAD
– V
IN
LOAD
= 0V
= 1V, V
OUT
= 500mA
= 1V, V
OUT
= 500mA
= 1V, V
OUT
= 500mA
= 1V, V
OUT
= 500mA
+ 0.5V, ΔV
OUT
= 0.5V
RIP
RIPPLE
RIPPLE
RIPPLE
= –5%
P-P
= 0.5V
= 0.5V
= 0.5V
, f
RIPPLE
P-P
P-P
P-P
, f
RIPPLE
, f
RIPPLE
, f
RIPPLE
= 120Hz,
= 120Hz,
= 120Hz,
= 120Hz,
70 dB
60 dB
58 dB
56 dB
1.8 A
l
550
= 0V 1 20 μA
OUT
OUT
OUT
OUT
= 1.2V, V
= 1.2V, V
= 1.5V, V
= 1.8V, V
= 0V
IN
= 0V
IN
= 0V
IN
= 0V
IN
0.5
10
10
10
5
15
15
15
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
μA
μA
mA
mA
μA
μA
mA
μA
μA
μA
μA
V
V
V
V
V
V
V
V
V
4
3021fc
Page 5
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
ELECTRICAL CHARACTERISTICS
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
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 LT3021 regulators are tested and specifi ed under pulse load
conditions such that T
at T
= 25°C. Performance at –40°C and 125°C is assured by design,
A
characterization and correlation with statistical process controls. The
LT3021I regulators are guaranteed over the full – 40ºC to 125ºC operating
junction temperature range.
Note 3: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active.
Continuous operation above the specifi ed maximum operating junction
temperature may impair device reliability.
Note 4: Maximum junction temperature limits operating conditions. The
regulated output voltage specifi cation does not apply for all possible
combinations of input voltage and output current. Limit the output current
range if operating at maximum input voltage. Limit the input voltage range
if operating at maximum output current.
Note 5: Typically the LT3021 supplies 500mA output current with a 1V
input supply. The guranteed minimum input voltage for 500mA output
current is 1.10V.
Note 6: The LT3021 is tested and specifi ed for these conditions with an
external resistor divider (20k and 30.1k) setting V
resistor divider adds 10μA of output load current. The line regulation and
load regulation specifi cations refer to the change in the 0.2V reference
≈ TA. The LT3021E regulators are 100% tested
J
OUT
= 25°C.
J
to 0.5V. The external
voltage, not the 0.5V output voltage. Specifi cations for fi xed output voltage
devices are referred to the output voltage.
Note 7: Dropout voltage is the minimum input to output voltage differential
needed to maintain regulation at a specifi ed output current. In dropout the
output voltage equals: (V
Note 8: GND pin current is tested with V
IN
– V
DROPOUT
).
= V
IN
OUT(NOMINAL)
+ 0.4V and a
current source load. GND pin current will increase in dropout. See GND pin
current curves in the Typical Performance Characteristics section.
Note 9: Adjust pin bias current fl ows out of the ADJ pin.
Note 10: Shutdown pin current fl ows into the SHDN pin.
Note 11: Reverse output current is tested with IN grounded and OUT
forced to the rated output voltage. This current fl ows into the OUT pin and
out of the GND pin. For fi xed voltage devices this includes the current in
the output resistor divider.
Note 12: The LT3021 is tested and specifi ed for these conditions with an
external resistor divider (20k and 100k) setting V
to 1.2V. The external
OUT
resistor divider adds 10μA of load current.
Note 13: Reverse current is higher for the case of (rated_output) < V
< V
because the no-load recovery circuitry is active in this region and is
IN,
trying to restore the output voltage to its nominal value.
Note 14: Minimum input voltage is the minimum voltage required by the
control circuit to regulate the output voltage and supply the full 500mA
rated current. This specifi cation is tested at V
= 0.5V. At higher output
OUT
voltages the minimum input voltage required for regulation will be equal to
the regulated output voltage V
plus the dropout voltage.
OUT
OUT
TYPICAL PERFORMANCE CHARACTERISTICS
Dropout Voltage Dropout Voltage Minimum Input Voltage
250
225
200
175
150
125
100
75
DROPOUT VOLTAGE (mV)
50
25
0
250
V
= 1.2V
OUT
TJ = 125°C
TJ = 25°C
0
200100 300
OUTPUT CURRENT (mA)
400
500
3021 G01
225
200
175
150
125
100
75
DROPOUT VOLTAGE (mV)
50
25
0
–50
250–25 50 75
TEMPERATURE (°C)
IL = 500mA
IL = 250mA
IL = 100mA
IL = 50mA
IL = 10mA
IL = 1mA
125100
3021 G02
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
0.4
MINIMUM INPUT VOLTAGE (V)
0.3
0.2
IL = 500mA
–50
250–25 50 75
TEMPERATURE (°C)
125100
3021 G16
3021fc
5
Page 6
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
TYPICAL PERFORMANCE CHARACTERISTICS
ADJ Pin Voltage ADJ Pin Bias Current Quiescent Current
206
204
202
200
198
ADJ PIN VOLTAGE (mV)
196
194
–50
250–25 50 75
TEMPERATURE (°C)
3021 G04
25
20
15
10
ADJ PIN BIAS CURRENT (nA)
5
0
125100
–50
250–25 50 75
TEMPERATURE (°C)
125100
3021 G11
250
VIN = 6V
V
225
OUT
= 0
I
L
200
175
150
125
100
75
QUIESCENT CURRENT (μA)
50
25
0
–50
= 1.2V
TEMPERATURE (°C)
V
SHDN
V
SHDN
250–25 50 75
= V
= 0V
IN
125100
3021 G05
Output Voltage Output Voltage Output Voltage
1.23
1.22
1.21
1.20
1.19
OUTPUT VOLTAGE (V)
1.18
1.17
–50
I
LOAD
= 1mA
–25 0
50 100 125
25 75
TEMPERATURE (°C)
3021 G28
1.53
1.52
1.51
1.50
1.49
OUTPUT VOLTAGE (V)
1.48
1.47
–50
I
LOAD
= 1mA
–25 0
50 100 125
25 75
TEMPERATURE (°C)
3021 G23
1.83
1.82
1.81
1.80
1.79
OUTPUT VOLTAGE (V)
1.78
1.77
–50
I
LOAD
–25 0
= 1mA
Quiescent Current Quiescent Current Quiescent Current
3.0
V
= 1.2V
OUT
= 0
I
L
= 25°C
T
J
2.5
2.0
1.5
V
= V
SHDN
IN
1.0
QUIESCENT CURRENT (mA)
0.5
V
SHDN
= 0V
3.0
V
= 1.5V
OUT
= 0
I
L
= 25°C
T
2.5
J
2.0
1.5
V
= V
SHDN
1.0
QUIESCENT CURRENT (mA)
0.5
3.0
V
= 1.8V
OUT
= 0
I
L
= 25°C
T
2.5
J
2.0
1.5
IN
1.0
V
= 0V
SHDN
QUIESCENT CURRENT (mA)
0.5
50 100 125
25 75
TEMPERATURE (°C)
V
= V
SHDN
IN
V
SHDN
3021 G22
= 0V
6
0
0
32158476
INPUT VOLTAGE (V)
109
3021 G03
0
2468
INPUT VOLTAGE (V)
10103579
3021 G26
0
2468
INPUT VOLTAGE (V)
10103579
3021 G27
3021fc
Page 7
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
TYPICAL PERFORMANCE CHARACTERISTICS
GND Pin Current GND Pin Current GND Pin Current
8
RL = 2.4Ω
7
6
5
4
3
GND PIN CURRENT (mA)
2
1
0
= 500mA
I
L
RL = 4.8Ω
= 250mA
I
L
RL = 12Ω
= 100mA
I
L
RL = 1.2k, IL = 1mA
213579
0
INPUT VOLTAGE (V)
4
RL = 24Ω
= 50mA
I
L
6
V
= 1.2V
OUT
= 25°C
T
J
RL = 120Ω
= 10mA
I
L
8
3021 G06
8
7
6
5
4
3
GND PIN CURRENT (mA)
2
1
10
0
RL = 3Ω
= 500mA
I
L
RL = 6Ω
= 250mA
I
L
RL = 15Ω
= 100mA
I
L
RL = 1.5k, IL = 1mA
2468
RL = 30Ω
I
INPUT VOLTAGE (V)
= 50mA
L
V
= 1.5V
OUT
= 25°C
T
J
RL = 150Ω
= 10mA
I
L
10103579
3021 G24
9
8
7
6
5
4
3
GND PIN CURRENT (mA)
2
1
0
V
= 1.8V
OUT
= 25°C
T
= 50mA
J
RL = 180Ω
= 10mA
I
L
3021 G25
RL = 3.6Ω
= 500mA
I
L
RL = 7.2Ω
= 250mA
I
L
RL = 18Ω
= 100mA
I
L
RL = 1.8k, IL = 1mA
2468
RL = 36Ω
I
L
INPUT VOLTAGE (V)
10103579
GND Pin Current vs I
10
V
= 10V
SHDN
9
8
7
6
5
4
3
GND PIN CURRENT (mA)
2
1
0
0
LOAD CURRENT (mA)
200100 300
LOAD
400
500
3021 G07
SHDN Pin Threshold SHDN Pin Input Current
1.0
IL = 1mA
0.9
0.8
0.7
0.6
0.5
0.4
0.3
SHDN PIN THRESHOLD (V)
0.2
0.1
0
–50
250–25 50 75
TEMPERATURE (°C)
125100
3021 G08
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
SHDN PIN INPUT CURRENT (μA)
0.5
0
213579
0
SHDN PIN VOLTAGE (V)
4
SHDN Pin Input Current Current Limit Reverse Output Current
5
V
= 10V
SHDN
4
3
2
1
SHDN PIN INPUT CURRENT (μA)
0
0
–50
250–25 50 75
TEMPERATURE (°C)
125100
3021 G10
2.0
1.8
1.6
1.4
1.2
1.0
0.8
CURRENT LIMIT (A)
0.6
0.4
0.2
0
0
–50
VIN = 10V
VIN = 1.7V
250–25 50 75
TEMPERATURE (°C)
V
= 0V
OUT
125100
3021 G12
500
VIN = 0V
= 1.2V
V
450
OUT
400
350
300
250
200
150
100
REVERSE OUTPUT CURRENT (μA)
50
0
0
–50
250–25 50 75
TEMPERATURE (°C)
6
8
10
3021 G09
125100
3021 G13
3021fc
7
Page 8
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
TYPICAL PERFORMANCE CHARACTERISTICS
Input Ripple Rejection Input Ripple Rejection
70
60
50
40
30
20
INPUT RIPPLE REJECTION (dB)
VIN = 1.5V + 50mV
10
= 0.5V
V
OUT
= 500mA
I
L
0
100
10 1k 10k 1M
RMS
FREQUENCY (Hz)
RIPPLE
C
C
OUT
OUT
100k
= 22μF
= 4.7μF
3021 G14
100
90
80
70
60
50
40
30
20
INPUT RIPPLE REJECTION (dB)
VIN = 1.5V + 0.5V
V
10
OUT
= 500mA
I
L
0
–50
= 0.5V
RIPPLE AT 120Hz
P-P
250–25 50 75
TEMPERATURE (°C)
3021 G15
Load Regulation
ΔIL = 1mA to 500mA
2.5
2.0
1.5
1.0
0.5
0
–0.5
–1.0
VIN = 1.15V
LOAD REGULATION (mV)
–1.5
–2.0
125100
–2.5
= 0.5V
V
OUT
*LOAD REGULATION NUMBER REFERS
TO CHANGE IN THE 200mV REFERENCE
VOLTAGE
–50
250–25 50 75
TEMPERATURE (°C)
125100
3021 G17
No-Load Recovery Threshold Output Noise Spectral Density
OUTPUT NOISE SPECTRAL DENSITY (μV/√Hz)
0.01
0.1
10
1
10
V
= 1.2V
OUT
= 500mA
I
L
= 4.7μF
C
OUT
1k 100k 1M100 10k
FREQUENCY (Hz)
18
16
14
12
10
8
6
4
OUTPUT SINK CURRENT (mA)
2
0
0
OUTPUT OVERSHOOT (%)
15105
20
3021 G20
RMS Output Noise vs Load
Current (10Hz to 100kHz) Transient Response
300
V
= 1.2V
OUT
= 4.7μF
C
OUT
250
)
RMS
200
150
100
OUTPUT NOISE (μV
50
0
0.01 1 10 100
0.1
LOAD CURRENT (mA)
3021 G19
V
OUT
50mV/DIV
I
OUT
500mA/DIV
= 50mA TO 500mA
I
OUT
= 1.5V
V
IN
= 1.2V
V
OUT
= 22μF
C
OUT
50μs/DIV
3021 G18
3021 G21
8
3021fc
Page 9
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
PIN FUNCTIONS
(DH Package/S8 Package)
OUT (Pins 3, 4/Pin 2): These pins supply power to the load.
Use a minimum output capacitor of 3.3μF to prevent oscillations. Applications with large load transients require larger
output capacitors to limit peak voltage transients. See the
Applications Information section for more information on
output capacitance and reverse output characteristics.
SENSE (Pin 7/Pin 3, Fixed Voltage Device Only): This pin
is the sense point for the internal resistor divider. It should
be tied directly to the OUT pins for best results.
ADJ (Pin 7/Pin 3): This pin is the inverting terminal to the
error amplifi er. Its typical input bias current of 20nA fl ows
out of the pin (see curve of ADJ Pin Bias Current vs Temperature in the Typical Performance Characteristics). The
ADJ pin reference voltage is 200mV (referred to GND).
AGND (Pin 8/Pin 4): Ground.
PGND (Pins 10, 17/Pin 6): Ground.
SHDN (Pin 9/Pin 5): The SHDN pin puts the LT3021 into
a low power state. Pulling the SHDN pin low turns the
output off. Drive the SHDN pin with either logic or an open
collector/drain device with a pull-up resistor. The pull-up
resistor supplies the pull-up current to the open collector/
drain logic, normally several microamperes, and the SHDN
pin current, typically 2.5μA. If unused, connect the SHDN
pin to V
. The LT3021 does not function if the SHDN pin
IN
is not connected.
IN (Pins 12, 14/Pin 8): These pins supply power to the
device. The LT3021 requires a bypass capacitor at IN if
it is more than six inches away from the main input fi lter
capacitor. The output impedance of a battery rises with
frequency, so include a bypass capacitor in battery-powered circuits. A bypass capacitor in the range of 3.3μF to
10μF suffi ces. The LT3021 withstands reverse voltages
on the IN pin with respect to ground and the OUT pin. In
the case of a reversed input, which occurs if a battery is
plugged in backwards, the LT3021 acts as if a diode is
in series with its input. No reverse current fl ows into the
LT3021 and no reverse voltage appears at the load. The
device protects itself and the load.
EXPOSED PAD (Pin 17, DH16 Package Only): Ground.
Solder Pin 17 to the PCB ground. Connect directly to Pins
8, 10 for best performance.
NC (Pins 1, 2, 5, 6, 11, 13, 15, 16/Pins 1, 7): No Connect.
No connect pins may be fl oated, tied to IN or tied to GND.
BLOCK DIAGRAM
SHDN
(9/5)
SHUTDOWN
BIAS CURRENT
AND
REFERENCE
GENERATOR
NOTE:
FOR LT3021 ADJUST PIN (7/3) IS CONNECTED TO
THE ADJUST PIN, R1 AND R2 ARE EXTERNAL.
FOR LT3021-1.X PIN (7/3) IS CONNECTED TO THE
OUTPUT SENSE PIN, R1 AND R2 ARE INTERNAL.
(DH Package/S8 Package)
THERMAL
SHUTDOWN
–
ERROR AMP
200mV
212mV
+
–
NO-LOAD
RECOVERY
+
CURRENT
FIXED
V
OUT
1.2V
1.5V
1.8V
25k
GAIN
R1
20k
20k
20k
R2
100k
130k
160k
IN
(12, 14/8)
R3
D1
Q3
Q1
D2
Q2
R2
R1
3021 BD
OUT
(3,4/2)
OUT SENSE
(7/3)
ADJ
(7/3)
GND
(8,10,17/4,6)
3021fc
9
Page 10
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
APPLICATIONS INFORMATION
The LT3021 is a very low dropout linear regulator capable
of 1V input supply operation. Devices supply 500mA of
output current and dropout voltage is typically 155mV.
Quiescent current is typically 120μA and drops to 3μA in
shutdown. The LT3021 incorporates several protection
features, making it ideal for use in battery-powered systems. The device protects itself against reverse-input and
reverse-output voltages. In battery backup applications
where the output is held up by a backup battery when the
input is pulled to ground, the LT3021 acts as if a diode is
in series with its output which prevents reverse current
fl ow. 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 10V without affecting
start-up or normal operation.
Adjustable Operation
The LT3021’s output voltage range is 0.2V to 9.5V. Figure
1 shows that the output voltage is set by the ratio of two
external resistors. The device regulates the output to maintain the ADJ pin voltage at 200mV referenced to ground.
The current in R1 equals 200mV/R1 and the current in R2
is the current in R1 minus the ADJ pin bias current. The
ADJ pin bias current of 20nA fl ows out of the pin. Use
the formula in Figure 1 to calculate output voltage. An R1
value of 20k sets the resistor divider current to 10μA. Note
that in shutdown the output is turned off and the divider
current is zero. Curves of ADJ Pin Voltage vs Temperature
and ADJ Pin Bias Current vs Temperature appear in the
Typical Performance Characteristics section.
IN
V
IN
SHDN
= 200mV
V
OUT
= 200mV
V
ADJ
= 20nA AT 25°C
I
ADJ
OUTPUT RANGE = 0.2V TO 9.5V
Figure 1. Adjustable Operation
OUT
LT3021
GND
R2
1 + – I
()
R1
ADJ
ADJ
R2
R1
3021 F01
(R2)
V
OUT
+
Specifi cations for output voltages greater than 200mV
are proportional to the ratio of desired output voltage to
200mV; (V
/200mV). For example, load regulation for
OUT
an output current change of 1mA to 500mA is typically
0.4mV at V
= 200mV. At V
ADJ
= 1.5V, load regulation is:
OUT
(1.5V/200mV) • (0.4mV) = 3mV
Output Capacitance and Transient Response
The LT3021’s design is stable with a wide range of output
capacitors, but is optimized for low ESR ceramic capacitors.
The output capacitor’s ESR affects stability, most notably
with small value capacitors. Use a minimum output capacitor of 3.3μF with an ESR of 0.2Ω or less to prevent
oscillations. The LT3021 is a low voltage device, and output
load transient response is a function of output capacitance.
Larger values of output capacitance decrease the peak
deviations and provide improved transient response for
larger load current changes. For output capacitor values
greater than 22μF a small feedforward capacitor with a
value of 300pF across the upper divider resistor (R2 in
Figure 1) is required. Under extremely low output current
conditions (I
oscillation (200Hz/8mV
< 30μA) a low frequency small signal
LOAD
at 1.2V output) can occur.
P-P
A minimum load of 100μA is recommended to prevent
this instability.
Give extra consideration to the use of ceramic capacitors.
Manufacturers make ceramic capacitors with a variety of
dielectrics, each with a different behavior across temperature and applied voltage. The most common dielectrics
are Z5U, Y5V, X5R and X7R. The Z5U and Y5V dielectrics
provide high C-V products in a small package at low cost,
but exhibit strong voltage and temperature coeffi cients.
The X5R and X7R dielectrics yield highly stable characterisitics and are more suitable for use as the output capacitor
at fractionally increased cost. The X5R and X7R dielectrics
both exhibit excellent voltage coeffi cient characteristics.
The X7R type works over a larger temperature range and
exhibits better temperature stability whereas X5R is less
expensive and is available in higher values. Figures 2 and
3 show voltage coeffi cient and temperature coeffi cient
comparisons between Y5V and X5R material.
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 microphone works. For a ceramic capacitor, the stress can be
induced by vibrations in the system or thermal transients.
The resulting voltages produced can cause appreciable
3021fc
10
Page 11
APPLICATIONS INFORMATION
20
0
–20
–40
–60
CHANGE IN VALUE (%)
–80
–100
0
Figure 2. Ceramic Capacitor DC Bias Characteristics
40
20
0
–20
–40
–60
CHANGE IN VALUE (%)
–80
BOTH CAPACITORS ARE 16V,
1210 CASE SIZE, 10μF
–100
–50
–25 0
Figure 3. Ceramic Capacitor Temperature Characteristics
amounts of noise. A ceramic capacitor produced Figure
4’s trace in response to light tapping from a pencil. Similar
vibration induced behavior can masquerade as increased
output voltage noise.
BOTH CAPACITORS ARE 16V,
1210 CASE SIZE, 10μF
X5R
Y5V
26
4
8
DC BIAS VOLTAGE (V)
50 100 125
25 75
TEMPERATURE (°C)
10
Y5V
12
X5R
14
16
3021 F02
3021 F03
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
1mV/DIV
C
I
LOAD
OUT
OUT
= 1.3V
= 10F
= 0
1ms/DIVV
Figure 4. Noise Resulting from Tapping on a Ceramic Capacitor
To eliminate this problem, the LT3021 incorporates a
no-load or light-load recovery circuit. This circuit is a
voltage-controlled current sink that signifi cantly improves
the light load transient response time by discharging the
output capacitor quickly and then turning off. The current sink turns on when the output voltage exceeds 6%
of the nominal output voltage. The current sink level is
then proportional to the overdrive above the threshold
up to a maximum of approximately 15mA. Consult the
curve in the Typical Performance Characteristics for the
No-Load Recovery Threshold.
If external circuitry forces the output above the no load
recovery circuit’s threshold, the current sink turns on in
an attempt to restore the output voltage to nominal. The
current sink remains on until the external circuitry releases
the output. However, if the external circuitry pulls the output
voltage above the input voltage, or the input falls below
the output, the LT3021 turns the current sink off and shuts
down the bias current/reference generator circuitry.
3021 F04
No-Load/Light-Load Recovery
A transient load step occurs when the output current changes
from its maximum level to zero current or a very small load
current. The output voltage responds by overshooting until
the regulator lowers the amount of current it delivers to the
new level. The regulator loop response time and the amount
of output capacitance control the amount of overshoot. Once
the regulator has decreased its output current, the current
provided by the resistor divider (which sets V
OUT
) is the
only current remaining to discharge the output capacitor
from the level to which it overshot. The amount of time it
takes for the output voltage to recover easily extends to
milliseconds with microamperes of divider current and a
few microfarads of output capacitance.
Thermal Considerations
The LT3021’s power handling capability is limited by
its maximum rated junction temperature of 125°C. The
power dissipated by the device is comprised of two
components:
1. Output current multiplied by the input-to-output voltage
differential: (I
OUT
IN
– V
OUT
) and
)(V
2. GND pin current multiplied by the input voltage:
)(VIN).
(I
GND
GND pin current is found by examining the GND pin current
curves in the Typical Performance Characteristics. Power
dissipation is equal to the sum of the two components
listed above.
3021fc
11
Page 12
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
APPLICATIONS INFORMATION
The LT3021 regulator has internal thermal limiting (with
hysteresis) designed to protect the device during overload
conditions. For normal continuous conditions, do not exceed the maximum junction temperature rating of 125°C.
Carefully consider all sources of thermal resistance from
junction to ambient including other heat sources mounted
in proximity to the LT3021.
The underside of the LT3021 DH package has exposed
2
metal (14mm
) from the lead frame to where the die is
attached. This allows heat to directly transfer from the
die junction to the printed circuit board metal to control
maximum operating junction temperature. The dual-in-line
pin arrangement allows metal to extend beyond the ends
of the package on the topside (component side) of a PCB.
Connect this metal to GND on the PCB. The multiple IN
and OUT pins of the LT3021 also assist in spreading heat
to the PCB.
The LT3021 S8 package has Pin 4 fused with the lead
frame. This also allows heat to transfer from the die to the
printed circuit board metal, therefore reducing the thermal
resistance. Copper board stiffeners and plated throughholes can also be used to spread the heat generated by
power devices.
The following tables list thermal resistance for several
different board sizes and copper areas for two different
packages. Measurements were taken in still air on 3/32”
FR-4 board with one ounce copper.
Table 1. Measured Thermal Resistance For DH Package
COPPER AREA
TOPSIDE* BACKSIDE BOARD AREA
2
2500mm
900mm
225mm
100mm
50mm
2500mm22500mm
2
2500mm22500mm
2
2500mm22500mm
2
2500mm22500mm
2
2500mm22500mm
THERMAL RESISTANCE
(JUNCTION-TO-AMBIENT)
2
2
2
2
2
30°C/W
35°C/W
50°C/W
55°C/W
65°C/W
Calculating Junction Temperature
Example: Given an output voltage of 1.2V, an input voltage
range of 1.8V ±10%, an output current range of 1mA to
500mA, and a maximum ambient temperature of 70°C,
what will the maximum junction temperature be for an
application using the DH package?
The power dissipated by the device is equal to:
I
OUT(MAX)(VIN(MAX)
– V
OUT
) + I
GND(VIN(MAX)
)
where
I
OUT(MAX)
V
IN(MAX)
I
GND
at (I
= 500mA
= 1.98V
= 500mA, V
OUT
= 1.98V) = 10mA
IN
so
P = 500mA(1.98V – 1.2V) + 10mA(1.98V) = 0.41W
The thermal resistance is in the range of 35°C/W to 70°C/W
depending on the copper area. So the junction temperature
rise above ambient is approximately equal to:
0.41W(52.5°C/W) = 21.5°C
The maximum junction temperature equals the maximum
junction temperature rise above ambient plus the maximum
ambient temperature or:
T
= 21.5°C + 70°C = 91.5°C
JMAX
Protection Features
The LT3021 incorporates several protection features
that make it ideal for use in battery-powered circuits.
In addition to the normal protection features associated
with monolithic regulators, such as current limiting and
thermal limiting, the device also protects against reverseinput voltages, reverse-output voltages and reverse output-to-input voltages.
Table 2. Measured Thermal Resistance For S8 Package
COPPER AREA
TOPSIDE* BACKSIDE BOARD AREA
2
2500mm
1000mm22500mm22500mm
225mm
100mm
50mm
*Device is mounted on topside.
2500mm22500mm
2
2500mm22500mm
2
2500mm22500mm
2
2500mm22500mm
THERMAL RESISTANCE
(JUNCTION-TO-AMBIENT)
2
2
2
2
2
70°C/W
70°C/W
78°C/W
84°C/W
96°C/W
12
Current limit protection and thermal overload protection
protect the device against current overload conditions at
the output of the device. For normal operation, do not
exceed a junction temperature of 125°C.
The IN pins of the device withstand reverse voltages of
10V. The LT3021 limits current fl ow to less than 1μA and
no negative voltage appears at OUT. The device protects
both itself and the load against batteries that are plugged
in backwards.
3021fc
Page 13
APPLICATIONS INFORMATION
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
The LT3021 incurs no damage if OUT is pulled below
ground. If IN is left open circuit or grounded, OUT can be
pulled below ground by 10V. No current fl ows from the
pass transistor connected to OUT. However, current fl ows
in (but is limited by) the resistor divider that sets the output voltage. Current fl ows from the bottom resistor in the
divider and from the ADJ pin’s internal clamp through the
top resistor in the divider to the external circuitry pulling
OUT below ground. If IN is powered by a voltage source,
OUT sources current equal to its current limit capability
and the LT3021 protects itself by thermal limiting. In this
case, grounding SHDN turns off the LT3021 and stops
OUT from sourcing current.
The LT3021 incurs no damage if the ADJ pin is pulled
above or below ground by 10V. If IN is left open circuit or
grounded and ADJ is pulled above ground, ADJ acts like a
25k resistor in series with a 1V clamp (one Schottky diode
in series with one diode). ADJ acts like a 25k resistor in
series with a Schottky diode if pulled below ground. If IN
is powered by a voltage source and ADJ is pulled below its
reference voltage, the LT3021 attempts to source its current
limit capability at OUT. The output voltage increases to V
– V
DROPOUT
the LT3021 supports. This condition can potentially damage external circuitry powered by the LT3021 if the output
voltage increases to an unregulated high voltage. If IN is
powered by a voltage source and ADJ is pulled above its
reference voltage, two situations can occur. If ADJ is pulled
slightly above its reference voltage, the LT3021 turns off
the pass transistor, no output current is sourced and the
output voltage decreases to either the voltage at ADJ or
less. If ADJ is pulled above its no load recovery threshold,
the no load recovery circuitry turns on and attempts to sink
current. OUT is actively pulled low and the output voltage
clamps at a Schottky diode above ground. Please note that
the behavior described above applies to the LT3021 only. If
a resistor divider is connected under the same conditions,
there will be additional V/R 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. In the case where the input is grounded, there is
less than 1μA of reverse output current.
with V
DROPOUT
set by whatever load current
IN
If the LT3021 IN pin is forced below the OUT pin or the
OUT pin is pulled above the IN pin, input current drops to
less than 10μA typically. This occurs if the LT3021 input is
connected to a discharged (low voltage) battery and either
a backup battery or a second regulator circuit holds up
the output. The state of the SHDN pin has no effect on the
reverse output current if OUT is pulled above IN.
Input Capacitance and Stability
The LT3021 is designed to be stable with a minimum
capacitance of 3.3μF placed at the IN pin. Ceramic capacitors with very low ESR may be used. However, in cases
where a long wire is used to connect a power supply to
the input of the LT3021 (and also from the ground of the
LT3021 back to the power supply ground), use of low value
input capacitors combined with an output load current of
20mA or greater may result in an unstable application.
This is due to the inductance of the wire forming an LC
tank circuit with the input capacitor and not a result of the
LT3021 being unstable.
The self-inductance, or isolated inductance, of a wire is
directly proportional to its length. However, the diameter
of a wire does not have a major infl uence on its self-inductance. For example, the self inductance of a 2-AWG
isolated wire with a diameter of 0.26 in. is about half the
inductance of a 30-AWG wire with a diameter of 0.01 in.
One foot of 30-AWG wire has 465nH of self inductance.
The overall self-inductance of a wire can be reduced in
two ways. One is to divide the current fl owing towards the
LT3021 between two parallel conductors and fl ows in the
same direction in each. In this case, the farther the wires
are placed apart from each other, the more inductance
will be reduced, up to a 50% reduction when placed a few
inches apart. Splitting the wires basically connects two
equal inductors in parallel. However, when placed in close
proximity from each other, mutual inductance is added to
the overall self inductance of the wires. The most effective
way to reduce overall inductance is to place the forward
and return-current conductors (the wire for the input and
the wire for ground) in very close proximity. Two 30-AWG
wires separated by 0.02 in. reduce the overall self-inductance to about one-fi fth of a single isolated wire.
3021fc
13
Page 14
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
APPLICATIONS INFORMATION
If the LT3021 is powered by a battery mounted in close
proximity on the same circuit board, a 3.3μF input capacitor
is suffi cient for stability. However, if the LT3021 is powered
by a distant supply, use a larger value input capacitor following the guideline of roughly 1μF (in addition to the 3.3μF
minimum) per 8 inches of wire length. As power supply
output impedance may vary, the minimum input capacitance needed to stabilize the application may also vary.
PACKAGE DESCRIPTION
DH Package
16-Lead Plastic DFN (5mm × 5mm)
(Reference LTC DWG # 05-08-1709)
0.70 ±0.05
5.50 ±0.05
4.10 ±0.05
3.45 ±0.05
(2 SIDES)
Extra capacitance may also be placed directly on the output
of the power supply; however, this will require an order of
magnitude more capacitance as opposed to placing extra
capacitance in close proximity to the LT3021. Furthermore,
series resistance may be placed between the supply and
the input of the LT3021 to stabilize the application; as little
as 0.1Ω to 0.5Ω will suffi ce.
5.00 ±0.10
5.00 ±0.10
R = 0.20
TYP
3.45 ± 0.10
(2 SIDES)
R = 0.115
TYP
0.40 ± 0.05
169
PACKAGE
OUTLINE
0.25 ± 0.05
0.50 BSC
4.10 ±0.05
(2 SIDES)
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
NOTE:
1. DRAWING PROPOSED TO BE MADE VARIATION OF VERSION (WJJD-1) IN JEDEC
PACKAGE OUTLINE MO-229
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE
PIN 1
TOP MARK
(SEE NOTE 6)
0.200 REF
0.75 ±0.05
0.00 – 0.05
0.25 ± 0.05
0.50 BSC
4.10 ±0.10
(2 SIDES)
BOTTOM VIEW—EXPOSED PAD
PIN 1
NOTCH
(DH16) DFN 0204
18
14
3021fc
Page 15
PACKAGE DESCRIPTION
.050 BSC
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
S8 Package
8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610)
.189 – .197
.045 ±.005
(4.801 – 5.004)
8
NOTE 3
7
6
5
.245
MIN
.030 ±.005
TYP
RECOMMENDED SOLDER PAD LAYOUT
.010 – .020
(0.254 – 0.508)
.008 – .010
(0.203 – 0.254)
NOTE:
1. DIMENSIONS IN
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)
×
°
45
.016 – .050
(0.406 – 1.270)
INCHES
(MILLIMETERS)
.160
±.005
.228 – .244
(5.791 – 6.197)
0°– 8° TYP
.053 – .069
(1.346 – 1.752)
.014 – .019
(0.355 – 0.483)
TYP
.150 – .157
(3.810 – 3.988)
NOTE 3
1
3
2
4
.004 – .010
(0.101 – 0.254)
.050
(1.270)
BSC
SO8 0303
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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
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15
Page 16
LT3021/LT3021-1.2/
LT3021-1.5/LT3021-1.8
RELATED PARTS
PART NUMBER DESCRIPTION COMMENTS
LT1121/LT1121HV 150mA, Micropower LDOs V
LT1129 700mA , Micropower LDO V
LT1761 100mA , Low Noise Micropower LDO VIN: 1.8V to 20V, V
LT1762 150mA , Low Noise Micropower LDO V
LT1763 500mA , Low Noise Micropower LDO V
LT1764/LT1764A 3A, Low Noise, Fast Transient Response LDOs V
LTC1844 150mA, Low Noise, Micropower VLDO VIN: 1.6V to 6.5V, V
LT1962 300mA , Low Noise Micropower LDO V
LT1963/LT1963A 1.5A, Low Noise, Fast Transient Response LDOs V
LT3010 50mA , High Voltage, Micropower LDO VIN: 3V to 80V, V
LT3020 100mA , Low Voltage LDO VIN: 0.9V to 10V, V
LTC3025 300mA, Low Voltage Micropower LDO V
LTC3026 1.5A, Low Input Voltage VLDO Regulator V
LT3150 Low V
, Fast Transient Response, VLDO Controller VIN: 1.1V to 10V, V
IN
: 4.2V to 30V/36V, V
IN
I
= 16μA, Reverse-Battery Protection, SOT-223, S8, Z Packages
SD
: 4.2V to 30V, V
IN
DD, SOT-223, S8, TO220-5, TSSOP20 Packages
Low Noise: < 20μV
ThinSOT Package
: 1.8V to 20V, V
IN
Low Noise: <20μV
: 1.8V to 20V, V
IN
Low Noise: < 20μV
: 2.7V to 20V, V
IN
Low Noise: <40μV
DD, TO220-5 Packages
I
< 1μA, Low Noise: < 30μV
SD
: 1.8V to 20V, V
IN
Low Noise: < 20μV
: 2.1V to 20V, V
IN
Low Noise: < 40μV
DD, TO220-5, SOT223, S8 Packages
Low Noise: <100μV
OUT
Exposed MS8 Package
Noise: <250μV
RMSP-P
DFN-8, MS8 Packages
: 0.9V to 5.5V, V
IN
Stable with 1μF Ceramic Capacitors, DFN-6 Package
: 1.14V to 3.5V (Boost Enabled), 1.14V to 5.5V (with External 5V),
IN
= 0.1V, IQ = 950μA, Stable with 10μF Ceramic Capacitors,
V
DO
10-Lead MSOP and DFN-10 Packages
, 1.4MHz Boost Converter Generates Gate Drive, SSOP16 Package
R
DS(ON)
: 3.75V to 30V, V
OUT
: 3.75V to 30V, V
OUT
: 1.22V to 20V, V
OUT
, Stable with 1μF Ceramic Capacitor,
RMSP-P
: 1.22V to 20V, V
OUT
, MS8 Package
RMSP-P
: 1.22V to 20V, V
OUT
, S8 Package
RMSP-P
: 1.21V to 20V, V
OUT
, “A” Version Stable with Ceramic Capacitors,
RMSP-P
= 1.25V, V
OUT(MIN)
: 1.22V to 20V, V
OUT
RMSP-P
: 1.21V to 20V, V
OUT
RMSP-P
, ThinSOT Package
RMS
, MS8 Package
, “A” Version Stable with Ceramic Capacitors,
: 1.275V to 60V, V
, Stable with 1μF Output Capacitor,
RMSP-P
: 0.2V to 5V (min), V
OUT
= 0.42V, IQ = 30μA,
DO
= 0.4V, IQ = 50μA, I
DO
= 0.3V, IQ = 20μA, I
DO
= 0.3V, IQ = 25μA, I
DO
= 0.3V, IQ = 30μA, I
DO
= 0.34V, IQ = 1mA, I
DO
= 0.09V, IQ = 35μA,
DO
= 0.27V, IQ = 30μA, I
DO
= 0.34V, IQ = 1mA, I
DO
= 0.3V, IQ = 30μA, I
DO
= 0.15V, IQ = 120μA,
DO
, Stable with 2.2μF Ceramic Capacitors,
: 0.4V to 3.6V (min), V
OUT
: 1.21V to 10V, V
OUT
DO
= 0.05V, IQ = 54μA,
DO
= Set by External MOSFET
SD
SD
SD
SD
SD
SD
SD
SD
= 16μA,
< 1μA,
< 1μA,
< 1μA,
< 1μA,
< 1μA,
< 1μA,
< 1μA,
16
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com
3021fc
LT 0608 REV C • PRINTED IN USA
© LINEAR TECHNOLOGY CORPORATION 2005
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