LT3012B
250mA, 4V to 80V
Low Dropout
Micropower Linear Regulator
FEATURES
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DESCRIPTIO
Wide Input Voltage Range: 4V to 80V
Low Quiescent Current: 40µA
Low Dropout Voltage: 400mV
Output Current: 250mA
No Protection Diodes Needed
Adjustable Output from 1.24V to 60V
Stable with 3.3µF Output Capacitor
Stable with Aluminum, Tantalum or Ceramic
Capacitors
Reverse-Battery Protection
No Reverse Current Flow from Output to Input
Thermal Limiting
Thermally Enhanced 16-Lead TSSOP and 12-Pin
(4mm
×
3mm) DFN Packages
The LT
®
3012B is a high voltage, micropower low dropout
linear regulator. The device is capable of supplying 250mA
of output current with a dropout voltage of 400mV. De-
signed for use in battery-powered or high voltage sys-
tems, the low quiescent current (40µA operating) makes
the LT3012B an ideal choice. Quiescent current is also well
controlled in dropout.
Other features of the LT3012B include the ability to oper-
ate with very small output capacitors. The regulators are
stable with only 3.3µF on the output while most older
devices require between 10µF and 100µF for stability.
Small ceramic capacitors can be used without any need for
series resistance (ESR) as is common with other regula-
tors. Internal protection circuitry includes reverse-battery
protection, current limiting, thermal limiting and reverse
current protection.
The device is available with an adjustable output with a
1.24V reference voltage. The LT3012B regulator is avail-
able in the 16-lead TSSOP and 12 pin low profile (0.75mm)
(4mm
×
3mm) DFN packages with an exposed pad for
enhanced thermal handling capability.
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
APPLICATIO S
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Low Current High Voltage Regulators
Regulator for Battery-Powered Systems
Telecom Applications
Automotive Applications
TYPICAL APPLICATIO
5V Supply
400
350
DROPOUT VOLTAGE (mV)
V
OUT
5V
250mA
3.3µF
300
250
200
150
100
50
0
0
50
100
150
200
OUTPUT CURRENT (mA)
250
IN
V
IN
5.4V TO
80V
1µF
OUT
LT3012B
ADJ
GND
249k
3012B
TA01
750k
U
Dropout Voltage
3012B
TA02
U
U
3012bf
1
LT3012B
ABSOLUTE
AXI U
RATI GS
(Note 1)
Storage Temperature Range
TSSOP Package ........................... –65°C to 150°C
DFN Package ............................... –65°C to 125°C
Operating Junction Temperature Range
(Notes 3, 9, 10) ........................... –40°C to 125°C
Lead Temperature (Soldering, 10 sec)............ 300°C
IN Pin Voltage ...................................................
±80V
OUT Pin Voltage ...............................................
±60V
IN to OUT Differential Voltage ...........................
±80V
ADJ Pin Voltage ..................................................
±7V
Output Short-Circuit Duration ..................... Indefinite
PACKAGE/ORDER I FOR ATIO
TOP VIEW
NC
OUT
OUT
ADJ
GND
NC
1
2
3
13
4
5
6
9
8
7
NC
NC
NC
12 NC
11 IN
10 IN
DE PACKAGE
12-LEAD (4mm
×
3mm) PLASTIC DFN
T
JMAX
= 125°C,
θ
JA
= 40°C/ W,
θ
JC
= 16°C/ W
EXPOSED PAD (PIN 13) IS GND
MUST BE SOLDERED TO PCB
ORDER PART NUMBER
LT3012BEDE
DE PART MARKING
3012B
Order Options
Tape and Reel: Add #TR
Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF
Lead Free Part Marking:
http://www.linear.com/leadfree/
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The
●
denotes specifications which apply over the full operating temperature range, otherwise specifications are at T
J
= 25°C.
PARAMETER
Minimum Input Voltage
ADJ Pin Voltage (Notes 2, 3)
Line Regulation
Load Regulation (Note 2)
CONDITIONS
I
LOAD
= 250mA
V
IN
= 4V, I
LOAD
= 1mA
4.5V < V
IN
< 80V, 1mA < I
LOAD
< 250mA
∆V
IN
= 4V to 80V, I
LOAD
= 1mA (Note 2)
V
IN
= 4.5V,
∆I
LOAD
= 1mA to 250mA
V
IN
= 4.5V,
∆I
LOAD
= 1mA to 250mA
●
●
●
●
2
U
U
W
W W
U
W
TOP VIEW
GND
NC
OUT
OUT
ADJ
GND
NC
GND
1
2
3
4
5
6
7
8
17
16 GND
15 NC
14 IN
13 IN
12 NC
11 NC
10 NC
9
GND
FE PACKAGE
16-LEAD PLASTIC TSSOP
T
JMAX
= 125°C,
θ
JA
= 40°C/ W,
θ
JC
= 16°C/ W
EXPOSED PAD (PIN 17) IS GND
MUST BE SOLDERED TO PCB
ORDER PART NUMBER
LT3012BEFE
FE PART MARKING
3012BEFE
MIN
1.225
1.2
TYP
4
1.24
1.24
0.1
7
MAX
4.5
1.255
1.28
5
12
25
UNITS
V
V
V
mV
mV
mV
3012bf
LT3012B
ELECTRICAL CHARACTERISTICS
The
●
denotes specifications which apply over the full operating temperature range, otherwise specifications are at T
J
= 25°C.
PARAMETER
Dropout Voltage
V
IN
= V
OUT(NOMINAL)
(Notes 4, 5)
CONDITIONS
I
LOAD
= 10mA
I
LOAD
= 10mA
I
LOAD
= 50mA
I
LOAD
= 50mA
I
LOAD
= 250mA
I
LOAD
= 250mA
GND Pin Current
V
IN
= 4.5V
(Notes 4, 6)
Output Voltage Noise
ADJ Pin Bias Current
Ripple Rejection
Current Limit
Reverse Output Current (Note 8)
I
LOAD
= 0mA
I
LOAD
= 100mA
I
LOAD
= 250mA
C
OUT
= 10µF, I
LOAD
= 250mA, BW = 10Hz to 100kHz
(Note 7)
V
IN
= 7V(Avg), V
RIPPLE
= 0.5V
P-P
, f
RIPPLE
= 120Hz, I
LOAD
= 250mA
V
IN
= 7V, V
OUT
= 0V
V
IN
= 4.5V,
∆V
OUT
= –0.1V (Note 2)
V
OUT
= 1.24V, V
IN
< 1.24V (Note 2)
●
65
270
12
25
●
MIN
TYP
160
250
MAX
230
300
340
420
490
620
100
18
100
UNITS
mV
mV
mV
mV
mV
mV
µA
mA
mA
µV
RMS
nA
dB
mA
mA
µA
●
400
●
●
●
40
3
10
100
30
75
400
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 LT3012B is tested and specified for these conditions with the
ADJ pin connected to the OUT pin.
Note 3:
Operating conditions are limited by maximum junction
temperature. The regulated output voltage specification will not apply for
all possible combinations of input voltage and output current. When
operating at maximum input voltage, the output current range must be
limited. When operating at maximum output current, the input voltage
range must be limited.
Note 4:
To satisfy requirements for minimum input voltage, the LT3012B
is tested and specified for these conditions with an external resistor divider
(249k bottom, 549k top) for an output voltage of 4V. The external resistor
divider will add a 5µA DC load on the output.
Note 5:
Dropout voltage is the minimum input to output voltage differential
needed to maintain regulation at a specified output current. In dropout, the
output voltage will be equal to (V
IN
– V
DROPOUT
).
Note 6:
GND pin current is tested with V
IN
= 4.5V and a current source
load. This means the device is tested while operating close to its dropout
region. This is the worst-case GND pin current. The GND pin current will
decrease slightly at higher input voltages.
Note 7:
ADJ pin bias current flows into the ADJ pin.
Note 8:
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 9:
The LT3012BE is guaranteed to meet performance specifications
from 0°C to 125°C operating junction temperature. Specifications over
the –40°C to 125°C operating junction temperature range are assured by
design, characterization and correlation with statistical process controls.
Note 10:
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 specified maximum operating
junction temperature may impair device reliability.
3012bf
3
LT3012B
TYPICAL PERFOR A CE CHARACTERISTICS
Typical Dropout Voltage
600
GUARANTEED DROPOUT VOLTAGE (mV)
500
DROPOUT VOLTAGE (mV)
T
J
= 125°C
DROPOUT VOLTAGE (mV)
400
300
200
100
0
T
J
= 25°C
0
50
100
150
200
OUTPUT CURRENT (mA)
Quiescent Current
100
V
IN
= 6V
90 R
L
=
∞
I =0
80
L
70
60
50
ADJ PIN VOLTAGE (V)
QUIESCENT CURRENT (µA)
1.250
1.245
1.240
1.235
1.230
1.225
QUIESCENT CURRENT (µA)
40
30
20
10
0
– 50 – 25
0
50
75
25
TEMPERATURE (°C)
100
125
GND Pin Current
1.2
1.0
T
J
= 25°C
*FOR V
OUT
= 1.24V
GND PIN CURRENT (mA)
GND PIN CURRENT (mA)
0.8
0.6
0.4
0.2
0
7
6
5
4
3
2
1
GND PIN CURRENT (mA)
R
L
= 49.6Ω
I
L
= 25mA*
R
L
= 124Ω
I
L
= 10mA*
R
L
= 1.24k
I
L
= 1mA*
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
4
U W
3012B G01
3012B G04
Guaranteed Dropout Voltage
600
500
400
300
200
100
0
= TEST POINTS
T
J
≤
125°C
Dropout Voltage
600
500
400
300
I
L
= 50mA
200
I
L
= 10mA
100
0
–50 –25
I
L
= 1mA
50
25
0
75
TEMPERATURE (°C)
100
125
I
L
= 250mA
I
L
= 100mA
T
J
≤
25°C
250
0
50
150
100
200
OUTPUT CURRENT (mA)
250
301B2 G02
3012B G03
ADJ Pin Voltage
1.260
1.255
I
L
= 1mA
80
70
60
50
40
30
20
10
0
50
75
25
TEMPERATURE (°C)
100
125
0
Quiescent Current
T
J
= 25°C
R
L
=
∞
V
OUT
= 1.24V
1.220
– 50 – 25
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
3012B G05
3012B G06
GND Pin Current
10
9
8
R
L
= 4.96Ω
I
L
= 250mA*
T
J
= 25°C, *FOR V
OUT
= 1.24V
10
GND Pin Current vs I
LOAD
V
IN
= 4.5V
9 T
J
= 25°C
= 1.24V
V
8
OUT
7
6
5
4
3
2
R
L
= 12.4Ω
I
L
= 100mA*
R
L
= 24.8Ω, I
L
= 50mA*
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
1
0
0
50
100
150
200
LOAD CURRENT (mA)
250
3012B G09
8
9
10
0
3012B G07
3012B G08
3012bf
LT3012B
TYPICAL PERFOR A CE CHARACTERISTICS
ADJ Pin Bias Current
50
45
ADJ PIN BIAS CURRENT (nA)
40
35
30
25
20
15
10
5
0
– 50 – 25
0
50
75
25
TEMPERATURE (°C)
100
125
CURRENT LIMIT (mA)
700
600
500
400
300
200
100
0
0
10
20
T
J
= 125°C
T
J
= 25°C
CURRENT LIMIT (mA)
Reverse Output Current
200
REVERSE OUTPUT CURRENT (µA)
REVERSE OUTPUT CURRENT (µA)
T
J
= 25°C
180 V
IN
= 0V
V
OUT
= V
ADJ
160
140
120
100 CURRENT FLOWS
80 INTO OUTPUT PIN
60
40
20
0
0
1
2
3 4 5 6 7 8
OUTPUT VOLTAGE (V)
9
10
ADJ
PIN CLAMP
(SEE APPLICATIONS
INFORMATION)
25
20
15
10
5
0
– 50 – 25
RIPPLE REJECTION (dB)
Input Ripple Rejection
100
V
IN
= 4.5V + 50mV
RMS
RIPPLE
90 I
LOAD
= 250mA
MINIMUM INPUT VOLTAGE (V)
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
80
RIPPLE REJECTION (dB)
70
60
50
40
30
20
10
0
10
100
1k
10k
FREQUENCY (Hz)
100k
1M
3012B G19
U W
3012B G13
3012B G16
Current Limit
1000
900
800
V
OUT
= 0V
Current Limit
700
600
500
400
300
200
100
V
IN
= 7V
V
OUT
= 0V
50
25
0
75
TEMPERATURE (°C)
100
125
30 40 50 60
INPUT VOLTAGE (V)
70
80
0
–50 –25
3012B G14
3012B G15
Reverse Output Current
35
30
V
IN
= 0V
V
OUT
= V
ADJ
= 1.24V
92
88
84
80
76
72
68
64
Input Ripple Rejection
V
IN
= 4.5V + 0.5V
P-P
RIPPLE AT f = 120Hz
I
L
= 250mA
V
OUT
= 1.24V
50
25
0
75
TEMPERATURE (°C)
100
125
0
75
50
25
TEMPERATURE (°C)
100
125
60
–50 –25
3012B G17
3012B G18
Minimum Input Voltage
I
LOAD
= 250mA
C
OUT
= 10µF
C
OUT
= 3.3µF
0
– 50 – 25
0
50
75
25
TEMPERATURE (°C)
100
125
3012B G20
3012bf
5
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