LT1762 - 150mA, Low Noise, LDO Micropower Regulators

LT1762 Series
150mA, Low Noise, LDO
Micropower Regulators
U
FEATURES
DESCRIPTIO
■
The LT ®1762 series are micropower, low noise, low
dropout regulators. The devices are capable of supplying
150mA of output current with a dropout voltage of 270mV.
Designed for use in battery-powered systems, the low
25µA quiescent current makes them an ideal choice.
Quiescent current is well controlled; it does not rise in
dropout as it does with many other regulators.
A key feature of the LT1762 regulators is low output noise.
With the addition of an external 0.01µF bypass capacitor,
output noise drops to 20µVRMS over a 10Hz to 100kHz
bandwidth. The LT1762 regulators are stable with output
capacitors as low as 2.2µF. Small ceramic capacitors can
be used without the series resistance required by other
regulators.
Internal protection circuitry includes reverse battery protection, current limiting, thermal limiting and reverse
current protection. The parts come in fixed output voltages of 2.5V, 3V, 3.3V and 5V, and as an adjustable device
with a 1.22V reference voltage. The LT1762 regulators are
available in the 8-lead MSOP package.
■
■
■
■
■
■
■
■
■
■
■
■
■
■
Low Noise: 20µVRMS (10Hz to 100kHz)
Low Quiescent Current: 25µA
Wide Input Voltage Range: 1.8V to 20V
Output Current: 150mA
Very Low Shutdown Current: < 1µA
Low Dropout Voltage: 270mV
No Protection Diodes Needed
Fixed Output Voltages: 2.5V, 3V, 3.3V, 5V
Adjustable Output from 1.22V to 20V
Stable with 2.2µF Output Capacitor
Stable with Aluminum, Tantalum or
Ceramic Capacitors
Reverse Battery Protection
No Reverse Current
Overcurrent and Overtemperature Protected
8-Lead MSOP Package
U
APPLICATIO S
■
■
■
■
Cellular Phones
Battery-Powered Systems
Frequency Synthesizers
Noise-Sensitive Instrumentation Systems
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
U
TYPICAL APPLICATIO
Dropout Voltage
3.3V Low Noise Regulator
400
IN
1µF
OUT
+
SENSE
LT1762-3.3
SHDN
BYP
GND
3.3V AT 150mA
20µVRMS NOISE
10µF
0.01µF
1762 TA01
350
DROPOUT VOLTAGE (mV)
VIN
3.7V TO
20V
300
250
200
150
100
50
0
0
20
40 60 80 100 120 140 160
OUTPUT CURRENT (mA)
1762 TA02
1762fa
1
LT1762 Series
W
U
PACKAGE/ORDER INFORMATION
W W
U
W
(Note 1)
IN Pin Voltage ........................................................ ±20V
OUT Pin Voltage .................................................... ±20V
Input to Output Differential Voltage ....................... ±20V
SENSE Pin Voltage ............................................... ±20V
ADJ Pin Voltage ...................................................... ±7V
BYP Pin Voltage.................................................... ±0.6V
SHDN Pin Voltage ................................................. ±20V
Output Short-Circut Duration .......................... Indefinite
Operating Junction Temperature Range
(Note 2) ............................................ – 40°C to 125°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
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/
U
ABSOLUTE MAXIMUM RATINGS
ORDER PART
NUMBER
TOP VIEW
OUT
SENSE/ADJ*
BYP
GND
8
7
6
5
1
2
3
4
IN
NC
NC
SHDN
MS8 PACKAGE
8-LEAD PLASTIC MSOP
*PIN 2: SENSE FOR LT1762-2.5/
LT1762-3/LT1762-3.3/LT1762-5
ADJ FOR LT1762
LT1762EMS8
LT1762EMS8-2.5
LT1762EMS8-3
LT1762EMS8-3.3
LT1762EMS8-5
MS8 PART MARKING
LTHF
LTHG
LTHH
LTHJ
LTHK
TJMAX = 150°C, θJA = 125°C/ W
SEE THE APPLICATIONS
INFORMATION SECTION.
Consult factory for Industrial and Military grade parts.
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C. (Note 2)
PARAMETER
CONDITIONS
Minimum Operating Voltage
ILOAD = 150mA
●
Regulated Output Voltage
(Note 4)
LT1762-2.5 VIN = 3V, ILOAD = 1mA
3.5V < VIN < 20V, 1mA < ILOAD < 150mA
●
LT1762-3
MIN
TYP
MAX
UNITS
1.8
2.3
V
2.475
2.435
2.5
2.5
2.525
2.565
V
V
●
2.970
2.925
3
3
3.030
3.075
V
V
●
3.267
3.220
3.3
3.3
3.333
3.380
V
V
VIN = 5.5V, ILOAD = 1mA
6V < VIN < 20V, 1mA < ILOAD < 150mA
●
4.950
4.875
5
5
5.050
5.125
V
V
VIN = 2V, ILOAD = 1mA
2.22V < VIN < 20V, 1mA < ILOAD < 150mA
●
1.208
1.190
1.22
1.22
1.232
1.250
V
V
1
1
1
1
1
5
5
5
5
5
mV
mV
mV
mV
mV
4
12
25
mV
mV
4
15
30
mV
mV
5
17
33
mV
mV
9
25
50
mV
mV
1
6
12
mV
mV
VIN = 3.5V, ILOAD = 1mA
4V < VIN < 20V, 1mA < ILOAD < 150mA
LT1762-3.3 VIN = 3.8V, ILOAD = 1mA
4.3V < VIN < 20V, 1mA < ILOAD < 150mA
LT1762-5
ADJ Pin Voltage
(Notes 3, 4)
LT1762
Line Regulation
LT1762-2.5
LT1762-3
LT1762-3.3
LT1762-5
LT1762 (Note 3)
∆VIN = 3V to 20V, ILOAD = 1mA
∆VIN = 3.5V to 20V, ILOAD = 1mA
∆VIN = 3.8V to 20V, ILOAD = 1mA
∆VIN = 5.5V to 20V, ILOAD = 1mA
∆VIN = 2V to 20V, ILOAD = 1mA
●
●
●
●
●
Load Regulation
LT1762-2.5
VIN = 3.5V, ∆ILOAD = 1mA to 150mA
VIN = 3.5V, ∆ILOAD = 1mA to 150mA
●
VIN = 4V, ∆ILOAD = 1mA to 150mA
VIN = 4V, ∆ILOAD = 1mA to 150mA
●
VIN = 4.3V, ∆ILOAD = 1mA to 150mA
VIN = 4.3V, ∆ILOAD = 1mA to 150mA
●
VIN = 6V, ∆ILOAD = 1mA to 150mA
VIN = 6V, ∆ILOAD = 1mA to 150mA
●
VIN = 2.22V, ∆ILOAD = 1mA to 150mA
VIN = 2.22V, ∆ILOAD = 1mA to 150mA
●
LT1762-3
LT1762-3.3
LT1762-5
LT1762 (Note 3)
1762fa
2
LT1762 Series
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C. (Note 2)
PARAMETER
CONDITIONS
MIN
Dropout Voltage
VIN = VOUT(NOMINAL)
ILOAD = 1mA
ILOAD = 1mA
●
(Notes 5, 6)
ILOAD = 10mA
ILOAD = 10mA
●
ILOAD = 50mA
ILOAD = 50mA
●
ILOAD = 150mA
ILOAD = 150mA
●
GND Pin Current
VIN = VOUT(NOMINAL)
(Notes 5, 7)
ILOAD = 0mA
ILOAD = 1mA
ILOAD = 10mA
ILOAD = 50mA
ILOAD = 150mA
●
●
●
●
●
Output Voltage Noise
COUT = 10µF, CBYP = 0.01µF, ILOAD = 150mA, BW = 10Hz to 100kHz
20
ADJ Pin Bias Current
(Notes 3, 8)
30
100
nA
Shutdown Threshold
VOUT = Off to On
VOUT = On to Off
0.8
0.65
2
V
V
●
●
0.25
TYP
MAX
UNITS
0.09
0.15
0.19
V
V
0.15
0.21
0.25
V
V
0.21
0.27
0.31
V
V
0.27
0.33
0.40
V
V
25
70
350
1.3
4
65
120
500
1.8
7
µA
µA
µA
mA
mA
SHDN Pin Current
(Note 9)
VSHDN = 0V
VSHDN = 20V
0.1
1
Quiescent Current in Shutdown
VIN = 6V, VSHDN = 0V
0.1
Ripple Rejection
VIN – VOUT = 1V (Avg), VRIPPLE = 0.5VP-P, fRIPPLE = 120Hz,
ILOAD = 150mA
Current Limit
VIN = 7V, VOUT = 0V
VIN = VOUT(NOMINAL) + 1V, ∆VOUT = – 0.1V
●
Input Reverse Leakage Current
VIN = – 20V, VOUT = 0V
●
Reverse Output Current
(Note 10)
LT1762-2.5
LT1762-3
LT1762-3.3
LT1762-5
LT1762 (Note 3)
VOUT = 2.5V, VIN < 2.5V
VOUT = 3V, VIN < 3V
VOUT = 3.3V, VIN < 3.3V
VOUT = 5V, VIN < 5V
VOUT = 1.22V, VIN < 1.22V
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 LT1762 regulators are tested and specified under pulse load
conditions such that TJ ≈ TA. The LT1762 is 100% tested at 25°C.
Performance at – 40°C and 125°C is assured by design, characterization
and correlation with statistical process controls.
Note 3: The LT1762 (adjustable version) is tested and specified for these
conditions with the ADJ pin connected to the OUT pin.
Note 4: 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.
50
µVRMS
µA
µA
1
µA
65
dB
400
mA
mA
160
10
10
10
10
5
1
mA
20
20
20
20
10
µA
µA
µA
µA
µA
Note 5: To satisfy requirements for minimum input voltage, the LT1762
(adjustable version) is tested and specified for these conditions with an
external resistor divider (two 250k resistors) for an output voltage of
2.44V. The external resistor divider will add a 5µA DC load on the output.
Note 6: 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: VIN – VDROPOUT.
Note 7: GND pin current is tested with VIN = VOUT(NOMINAL) and a current
source load. This means the device is tested while operating in its dropout
region. This is the worst-case GND pin current. The GND pin current will
decrease slightly at higher input voltages.
Note 8: ADJ pin bias current flows into the ADJ pin.
Note 9: SHDN pin current flows into the SHDN pin.
Note 10: 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.
1762fa
3
LT1762 Series
U W
TYPICAL PERFORMANCE CHARACTERISTICS
Guaranteed Dropout Voltage
450
450
400
400
350
TJ = 125°C
300
250
200
TJ = 25°C
150
= TEST POINTS
450
TJ ≤ 125°C
350
300
TJ ≤ 25°C
250
200
150
400
350
250
IL = 50mA
200
IL = 10mA
150
100
100
50
50
50
0
20
60 80 100 120 140 160
LOAD CURRENT (mA)
0
20
40
60 80 100 120 140 160
LOAD CURRENT (mA)
1762 G01
40
15
10
5
IL = 1mA
2.53
3.045
2.52
3.030
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
QUIESCENT CURRENT (µA)
VSHDN = VIN
20
3.060
IL = 1mA
25
2.51
2.50
2.49
2.48
2.47
0
–50 –25
0
25
50
75
100
3.015
3.000
2.985
2.970
2.955
2.46
–50 –25
125
TEMPERATURE (°C)
0
25
50
75
100
2.940
–50 –25
125
TEMPERATURE (°C)
1762 G04
3.360
3.330
5.050
1.230
3.240
–50 –25
ADJ PIN VOLTAGE (V)
1.235
OUTPUT VOLTAGE (V)
5.075
3.255
5.025
5.000
4.975
4.950
4.925
0
25
50
75
100
125
TEMPERATURE (°C)
125
4.900
–50 –25
IL = 1mA
1.225
1.220
1.215
1.210
1.205
0
25
50
75
100
125
TEMPERATURE (°C)
1762 G07
100
1.240
3.345
3.270
75
LT1762
ADJ Pin Voltage
IL = 1mA
3.285
50
1762 G06
5.100
IL = 1mA
3.300
25
TEMPERATURE (°C)
LT1762-5
Output Voltage
3.315
0
1762 G05
LT1762-3.3
Output Voltage
125
LT1762-3
Output Voltage
2.54
VIN = 6V
RL = ∞, IL = 0 (LT1762-2.5/-3/-3.3/-5)
RL = 250k, IL = 5µA (LT1762)
100
1762 G03
LT1762-2.5
Output Voltage
30
50
25
0
75
TEMPERATURE (°C)
1762 G02
Quiescent Current
35
IL = 1mA
0
–50 –25
0
40
IL = 150mA
300
100
0
OUTPUT VOLTAGE (V)
Dropout Voltage
500
DROPOUT VOLTAGE (mV)
500
DROPOUT VOLTAGE (mV)
DROPOUT VOLTAGE (mV)
Typical Dropout Voltage
500
1.200
–50 –25
0
25
50
75
100
125
TEMPERATURE (°C)
1762 G08
1762 G09
1762fa
4
LT1762 Series
U W
TYPICAL PERFORMANCE CHARACTERISTICS
LT1762-2.5
Quiescent Current
LT1762-3
Quiescent Current
400
400
400
TJ = 25°C
RL = ∞
250
200
150
100
VSHDN = VIN
VSHDN = 0V
0
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
9
8
300
250
200
150
100
VSHDN = VIN
50
150
100
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
150
VSHDN = VIN
100
2
3 4 5 6 7
INPUT VOLTAGE (V)
VSHDN = VIN
20
TJ = 25°C
RL = 250k
15
10
600
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
500
400
RL = 250Ω
IL = 10mA*
300
200
RL = 2.5k
IL = 1mA*
100
0
2
4
0
LT1762-3.3
GND Pin Current
700
500
400
RL = 300Ω
IL = 10mA*
300
200
RL = 3k
IL = 1mA*
100
RL = 132Ω
IL = 25mA*
600
700
400
RL = 330Ω
IL = 10mA*
300
200
RL = 3.3k
IL = 1mA*
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
1762 G16
0
1
2
9
10
3 4 5 6 7
INPUT VOLTAGE (V)
RL = 200Ω
IL = 25mA*
600
TJ = 25°C
VIN = VSHDN
*FOR VOUT = 5V
500
400
300
200
RL = 5k
IL = 1mA*
100
0
0
8
800
TJ = 25°C
VIN = VSHDN
*FOR VOUT = 3.3V
500
100
0
3 4 5 6 7
INPUT VOLTAGE (V)
LT1762-5
GND Pin Current
GND PIN CURRENT (µA)
600
TJ = 25°C
VIN = VSHDN
*FOR VOUT = 3V
GND PIN CURRENT (µA)
RL = 120Ω
IL = 25mA*
2
1762 G15
800
700
1
1762 G14
800
GND PIN CURRENT (µA)
0
6 8 10 12 14 16 18 20
INPUT VOLTAGE (V)
1762 G13
LT1762-3
GND Pin Current
10
RL = 100Ω
IL = 25mA*
VSHDN = 0V
0
0
9
TJ = 25°C
VIN = VSHDN
*FOR VOUT = 2.5V
700
5
VSHDN = 0V
0
8
LT1762-2.5
GND Pin Current
GND PIN CURRENT (µA)
QUIESCENT CURRENT (µA)
200
1
800
25
250
VSHDN = 0V
1762 G12
30
TJ = 25°C
RL = ∞
300
VSHDN = VIN
0
10
LT1762
Quiescent Current
400
QUIESCENT CURRENT (µA)
200
1762 G11
LT1762-5
Quiescent Current
50
250
0
0
1762 G10
350
300
50
VSHDN = 0V
0
10
TJ = 25°C
RL = ∞
350
QUIESCENT CURRENT (µA)
300
50
TJ = 25°C
RL = ∞
350
QUIESCENT CURRENT (µA)
350
QUIESCENT CURRENT (µA)
LT1762-3.3
Quiescent Current
8
9
10
1762 G17
RL = 500Ω
IL = 10mA*
0
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
1762 G18
1762fa
5
LT1762 Series
U W
TYPICAL PERFORMANCE CHARACTERISTICS
LT1762
GND Pin Current
600
RL = 48.8Ω
IL = 25mA*
500
400
RL = 122Ω
IL = 10mA*
300
200
4.0
3.5
2.5
RL = 25Ω
IL = 100mA*
2.0
1.5
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
LT1762-3.3
GND Pin Current
2.5
RL = 33Ω
IL = 100mA*
2.0
1.5
4.0
3 4 5 6 7
INPUT VOLTAGE (V)
2
8
9
3.0
2.5
RL = 50Ω
IL = 100mA*
2.0
1.5
0.9
3.0
2.5
2.0
1.5
1.0
0.5
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
2.0
40
60 80 100 120 140 160
OUTPUT CURRENT (mA)
1762 G25
RL = 24.4Ω
IL = 50mA*
1.5
10
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
1762 G24
SHDN Pin Threshold
(Off-to-On)
1.0
IL = 1mA
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0
–50 –25
0.8
0.7
IL = 150mA
0.6
0.5
IL = 1mA
0.4
0.3
0.2
0.1
0.1
0
RL = 12.2Ω
IL = 100mA*
2.5
0
1
SHDN PIN THRESHOLD (V)
SHDN PIN THRESHOLD (V)
3.5
20
3.0
0.5
1.0
VIN = VOUT(NOMINAL) + 1V
10
RL = 8.07Ω
IL = 150mA*
3.5
SHDN Pin Threshold
(On-to-Off)
5.0
0
4.0
1762 G23
GND Pin Current vs ILOAD
9
1.0
RL = 100Ω
IL = 50mA*
0
10
4.0
8
TJ = 25°C
VIN = VSHDN
*FOR VOUT = 1.22V
4.5
1762 G22
4.5
3 4 5 6 7
INPUT VOLTAGE (V)
1762 G21
0
1
2
LT1762
GND Pin Current
RL = 33.3Ω
IL = 150mA*
3.5
0.5
0
0
1
5.0
1.0
RL = 66Ω
IL = 50mA*
0.5
RL = 60Ω
IL = 50mA*
0
GND PIN CURRENT (mA)
GND PIN CURRENT (mA)
GND PIN CURRENT (mA)
3.0
1.5
10
TJ = 25°C
VIN = VSHDN
*FOR VOUT = 5V
4.5
RL = 22Ω
IL = 150mA*
1.0
GND PIN CURRENT (mA)
9
5.0
TJ = 25°C
VIN = VSHDN
*FOR VOUT = 3.3V
3.5
RL = 30Ω
IL = 100mA*
2.0
LT1762-5
GND Pin Current
5.0
4.0
2.5
1762 G20
1762 G19
4.5
RL = 20Ω
IL = 150mA*
3.0
0
0
10
3.5
0.5
0
0
4.0
1.0
RL = 50Ω
IL = 50mA*
0.5
0
TJ = 25°C
VIN = VSHDN
*FOR VOUT = 3V
4.5
RL = 16.7Ω
IL = 150mA*
3.0
1.0
RL = 1.22k
IL = 1mA*
100
5.0
TJ = 25°C
VIN = VSHDN
*FOR VOUT = 2.5V
4.5
GND PIN CURRENT (mA)
GND PIN CURRENT (µA)
5.0
TJ = 25°C
VIN = VSHDN
*FOR VOUT = 1.22V
700
LT1762-3
GND Pin Current
GND PIN CURRENT (mA)
800
LT1762-2.5
GND Pin Current
50
25
0
75
TEMPERATURE (°C)
100
125
1762 G26
0
–50 –25
50
25
0
75
TEMPERATURE (°C)
100
125
1762 G27
1762fa
6
LT1762 Series
U W
TYPICAL PERFORMANCE CHARACTERISTICS
SHDN Pin Input Current
SHDN Pin Input Current
1.4
1.6
1.2
1.4
ADJ Pin Bias Current
140
1.0
0.8
0.6
0.4
0.2
0
1
2
3 4 5 6 7 8
SHDN PIN VOLTAGE (V)
9
1.2
1.0
0.8
0.6
0.4
0
–50 –25
10
25
0
75
50
100
Current Limit
300
250
200
150
100
VIN = 7V
VOUT = 0V
400
350
300
250
200
150
100
50
50
7
6
50
25
0
75
TEMPERATURE (°C)
100
1762 G31
LT1762-2.5/-3/-3.3/-5
10
LT1762
5
50
LT1762-2.5
40
LT1762-3
30
20
LT1762-3.3
LT1762-5
0
125
0
1
2
3 4 5 6 7 8
OUTPUT VOLTAGE (V)
9
10
1762 G33
Input Ripple Rejection
80
80
70
70
60
60
50
COUT = 10µF
40
30
IL = 150mA
VIN = VOUT(NOMINAL) +
1V + 50mVRMS RIPPLE
CBYP = 0
20
10
COUT = 2.2µF
100
125
1762 G34
CBYP = 1000pF
50
CBYP = 100pF
40
30
20
IL = 150mA
VIN = VOUT(NOMINAL) +
1V + 50mVRMS RIPPLE
COUT = 10µF
10
0
50
25
0
75
TEMPERATURE (°C)
60
LT1762
CBYP = 0.01µF
15
0
–50 –25
70
Input Ripple Rejection
RIPPLE REJECTION (dB)
REVERSE OUTPUT CURRENT (µA)
20
80
1762 G32
Reverse Output Current
VIN = 0V
VOUT = 1.22V (LT1762)
VOUT = 2.5V (LT1762-2.5)
VOUT = 3V (LT1762-3)
VOUT = 3.3V (LT1762-3.3)
VOUT = 5V (LT1762-5)
TJ = 25°C, VIN = 0V
CURRENT FLOWS
INTO OUTPUT PIN
VOUT = VSENSE
(LT1762-2.5/-3/-3.3/-5)
VOUT = VADJ (LT1762)
90
10
0
–50 –25
0
25
100
REVERSE OUTPUT CURRENT (µA)
SHORT-CIRCUIT CURRENT (mA)
SHORT-CIRCUIT CURRENT (mA)
350
125
100
Reverse Output Current
450
400
30
50
25
0
75
TEMPERATURE (°C)
1762 G30
Current Limit
VOUT = 0V
4
3
2
5
INPUT VOLTAGE (V)
40
0
–50 –25
125
500
1
60
1762 G29
500
0
80
TEMPERATURE (°C)
1762 G28
450
100
20
0.2
RIPPLE REJECTION (dB)
0
120
ADJ PIN BIAS CURRENT (nA)
SHDN PIN INPUT CURRENT (mA)
SHDN PIN INPUT CURRENT (µA)
VSHDN = 20V
0
10
100
1k
10k
FREQUENCY (Hz)
100k
1M
1762 G35
10
100
1k
10k
FREQUENCY (Hz)
100k
1M
1762 G36
1762fa
7
LT1762 Series
U W
TYPICAL PERFORMANCE CHARACTERISTICS
LT1762
Minimum Input Voltage
Ripple Rejection
MINIMUM INPUT VOLTAGE (V)
RIPPLE REJECTION (dB)
64
62
60
58
54
VIN = VOUT (NOMINAL) +
1V + 0.5VP-P RIPPLE
AT f = 120Hz
IL = 150mA
52
–50 –25
0
25
VOUT = 1.22V
IL = 150mA
1.75
1.50
IL = 1mA
1.25
1.00
0.75
0.50
–5
–10
75
100
0
–50 –25
125
50
25
0
75
TEMPERATURE (°C)
LT1762-5
OUTPUT NOISE SPECTRAL DENSITY (µV/√Hz)
COUT = 10µF
IL = 150mA
LT1762-3.3
1
LT1762-2.5
LT1762-3
0.1
100
25
1k
10k
FREQUENCY (Hz)
75
100
125
1762 G39
100k
10
COUT = 10µF
IL = 150mA
CBYP = 1000pF
LT1762-5
1
CBYP = 100pF
LT1762
0.1
CBYP = 0.01µF
0.01
10
100
1k
10k
FREQUENCY (Hz)
100k
1762 G41
1762 G40
RMS Output Noise vs
Bypass Capacitor
RMS Output Noise vs
Load Current (10Hz to 100kHz)
160
160
COUT = 10µF
IL = 150mA
f = 10Hz TO 100kHz
140
LT1762-5
120
LT1762-3.3
100
LT1762-3
80
60
140
OUTPUT NOISE (µVRMS)
OUTPUT NOISE (µVRMS)
50
Output Noise Spectral Density
10
0.01
10
0
1762 G38
Output Noise Spectral Density
CBYP = 0
LT1762
VIN = VOUT(NOMINAL) + 1V
∆IL = 1mA TO 150mA
TEMPERATURE (°C)
1762 G37
LT1762-5
LT1762-3.3
–25
–50 –25
125
100
LT1762-2.5
–15
–20
TEMPERATURE (°C)
OUTPUT NOISE SPECTRAL DENSITY (µV/√Hz)
LT1762-3
0.25
50
LT1762
0
2.00
LOAD REGULATION (mV)
2.25
66
56
Load Regulation
5
2.50
68
LT1762
40
COUT = 10µF
CBYP = 0
CBYP = 0.01µF
100
80
LT1762
60
40
LT1762-2.5
20
LT1762-5
20
0
10
100
1000
10000
CBYP (pF)
1762 G42
LT1762-5
120
0
0.01
LT1762
0.1
10
100
1
LOAD CURRENT (mA)
1000
1762 G43
1762fa
8
LT1762 Series
U W
TYPICAL PERFORMANCE CHARACTERISTICS
LT1762-5
10Hz to 100kHz Output Noise
CBYP = 100pF
LT1762-5
10Hz to 100kHz Output Noise
CBYP = 0
VOUT
100µV/DIV
VOUT
100µV/DIV
1ms/DIV
1ms/DIV
COUT = 10µF
IL = 150mA
COUT = 10µF
IL = 150mA
1762 G44
LT1762-5
10Hz to 100kHz Output Noise
CBYP = 1000pF
1762 G45
LT1762-5
10Hz to 100kHz Output Noise
CBYP = 0.01µF
VOUT
100µV/DIV
VOUT
100µV/DIV
1ms/DIV
1ms/DIV
COUT = 10µF
IL = 150mA
COUT = 10µF
IL = 150mA
1762 G46
1762 G47
LT1762-5
Transient Response
CBYP = 0.01µF
LT1762-5
Transient Response
CBYP = 0
VIN = 6V
CIN = 10µF
COUT = 10µF
0.2
0.1
0
–0.1
–0.2
OUTPUT VOLTAGE
DEVIATION (V)
OUTPUT VOLTAGE
DEVIATION (V)
0.3
VIN = 6V
CIN = 10µF
COUT = 10µF
0.04
0.02
0
–0.02
–0.04
LOAD CURRENT
(mA)
LOAD CURRENT
(mA)
–0.3
150
100
50
0
0
400
800
1200
TIME (µs)
1600
2000
1762 G48
150
100
50
0
0
40
80
120
TIME (µs)
160
200
1762 G49
1762fa
9
LT1762 Series
U
U
U
PIN FUNCTIONS
OUT (Pin 1): Output. The output supplies power to the
load. A minimum output capacitor of 2.2µF 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.
SENSE (Pin 2): Output Sense. For fixed voltage versions
of the LT1762 (LT1762-2.5/LT1762-3/LT1762-3.3/
LT1762-5), 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 critical applications, small voltage drops are
caused by the resistance (RP) of PC traces between the
regulator and the 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 10µA 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 (Pin 2): Adjust. For the adjustable LT1762, this is the
input to the error amplifier. This pin is internally clamped
to ±7V. It has a bias current of 30nA which flows into the
pin (see curve of ADJ Pin Bias Current vs Temperature in
the Typical Performance Characteristics). The ADJ pin
voltage is 1.22V referenced to ground and the output
voltage range is 1.22V to 20V.
BYP (Pins 3): Bypass. The BYP pin is used to bypass the
reference of the LT1762 regulators to achieve low noise
performance from the regulator. The BYP pin is clamped
internally to ±0.6V (one VBE). A small capacitor from the
output to this pin will bypass the reference to lower the
output voltage noise. A maximum value of 0.01µF can be
used for reducing output voltage noise to a typical 20µVRMS
over a 10Hz to 100kHz bandwidth. If not used, this pin
must be left unconnected.
GND (Pin 4): Ground.
SHDN (Pin5): Shutdown. The SHDN pin is used to put the
LT1762 regulators into a low power shutdown state. The
output will be off when the SHDN pin is pulled low. The
SHDN pin can be driven either by 5V logic or opencollector logic with a pull-up resistor. The pull-up resistor
is required to supply the pull-up current of the opencollector gate, normally several microamperes, and the
SHDN pin current, typically 1µA. If unused, the SHDN pin
must be connected to VIN. The device will be in low power
shutdown state if the SHDN pin is not connected.
IN (Pin 8): 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
LT1762 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.
8
IN
OUT
1
RP
LT1762
+
VIN
5
SHDN
SENSE
GND
+
2
LOAD
4
RP
1762 F01
Figure 1. Kelvin Sense Connection
1762fa
10
LT1762 Series
U
W
U
U
APPLICATIONS INFORMATION
The LT1762 series are 150mA low dropout regulators with
micropower quiescent current and shutdown. The devices
are capable of supplying 150mA at a dropout voltage of
270mV. Output voltage noise can be lowered to 20µVRMS
over a 10Hz to 100kHz bandwidth with the addition of a
0.01µF reference bypass capacitor. Additionally, the reference bypass capacitor will improve transient response of
the regulator, lowering the settling time for transient load
conditions. The low operating quiescent current (25µA)
drops to less than 1µA in shutdown. In addition to the low
quiescent current, the LT1762 regulators incorporate several protection features which make them ideal for use in
battery-powered systems. 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 LT1762-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.
Adjustable Operation
The adjustable version of the LT1762 has an output
voltage range of 1.22V 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 ADJ pin voltage
IN
VIN
OUT
VOUT
+
LT1762
R2
ADJ
GND
R1
1762 F02
⎛ R2⎞
VOUT = 1.22V ⎜ 1 + ⎟ + (IADJ )(R2)
⎝ R1⎠
VADJ = 1.22V
IADJ = 30nA AT 25°C
OUTPUT RANGE = 1.22V TO 20V
Figure 2. Adjustable Operation
at 1.22V referenced to ground. The current in R1 is then
equal to 1.22V/R1 and the current in R2 is the current in R1
plus the ADJ pin bias current. The ADJ pin bias current,
30nA 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 no greater than 250k
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. Curves of ADJ Pin
Voltage vs Temperature and ADJ Pin Bias Current vs
Temperature appear in the Typical Performance Characteristics section.
The adjustable device is tested and specified with the ADJ
pin tied to the OUT pin for an output voltage of 1.22V.
Specifications for output voltages greater than 1.22V will
be proportional to the ratio of the desired output voltage to
1.22V: VOUT/1.22V. For example, load regulation for an
output current change of 1mA to 150mA is –1mV typical
at VOUT = 1.22V. At VOUT = 12V, load regulation is:
(12V/1.22V)(–1mV) = – 9.8mV
Bypass Capacitance and Low Noise Performance
The LT1762 regulators may be used with the addition of a
bypass capacitor from VOUT to the BYP pin to lower output
voltage noise. A good quality low leakage capacitor is
recommended. This capacitor will bypass the reference of
the regulator, providing a low frequency noise pole. The
noise pole provided by this bypass capacitor will lower the
output voltage noise to as low as 20µVRMS with the
addition of a 0.01µF bypass capacitor. Using a bypass
capacitor has the added benefit of improving transient
response. With no bypass capacitor and a 10µF output
capacitor, a 10mA to 150mA load step will settle to within
1% of its final value in less than 100µs. With the addition
of a 0.01µF bypass capacitor, the output will stay within
1% for a 10mA to 150mA load step (see LT1762-5
Transient Response in the Typical Performance Characteristics). However, regulator start-up time is proportional
to the size of the bypass capacitor, slowing to 15ms with
a 0.01µF bypass capacitor and 10µF output capacitor.
1762fa
11
LT1762 Series
U
W
U
U
APPLICATIONS INFORMATION
The LT1762 regulators are designed to be stable with a
wide range of output capacitors. The ESR of the output
capacitor affects stability, most notably with small capacitors. A minimum output capacitor of 2.2µF with an ESR of
3Ω or less is recommended to prevent oscillations. The
LT1762-X is a micropower device and output transient
response will be a function of output capacitance. Larger
values of output capacitance decrease the peak deviations
and provide improved transient response for larger load
current changes. Bypass capacitors, used to decouple
individual components powered by the LT1762-X, will
increase the effective output capacitor value. With larger
capacitors used to bypass the reference (for low noise
operation), larger values of output capacitors are needed.
For 100pF of bypass capacitance, 3.3µF of output capacitor is recommended. With a 330pF bypass capacitor or
larger, a 4.7µF output capacitor is recommended. The
shaded region of Figure 3 defines the range over which the
LT1762 regulators are stable. The minimum ESR needed
is defined by the amount of bypass capacitance used,
while the maximum ESR is 3Ω.
Extra consideration must be given to the use of ceramic
capacitors. Ceramic capacitors are manufactured with a
variety of dielectrics, each with different behavior across
temperature and applied voltage. The most common dielectrics used are specified with EIA temperature characteristic codes of Z5U, Y5V, X5R and X7R. The Z5U and Y5V
dielectrics are good for providing high capacitances in a
20
X5R
–20
–40
–60
Y5V
–80
–100
20
CHANGE IN VALUE (%)
2.0
1.5
CBYP = 0
CBYP = 100pF
CBYP = 330pF
CBYP ≥ 3300pF
1.0
0.5
1
3
2
4 5 6 7 8 9 10
OUTPUT CAPACITANCE (µF)
1762 F03
Figure 3. Stability
4
14
8
6
10 12
DC BIAS VOLTAGE (V)
16
X5R
0
–20
–40
Y5V
–60
–80
0
2
Figure 4. Ceramic Capacitor DC Bias Characteristics
40
STABLE REGION
0
1762 F04
3.5
2.5
BOTH CAPACITORS ARE 16V,
1210 CASE SIZE, 10µF
0
4.0
3.0
ESR (Ω)
small package, but they tend to have strong voltage and
temperature coefficients as shown in Figures 4 and 5.
When used with a 5V regulator, a 16V 10µF Y5V capacitor
can exhibit an effective value as low as 1µF to 2µF for the
DC bias voltage applied and 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. Care still must be exercised
when using X5R and X7R capacitors; the X5R and X7R
codes only specify operating temperature range and maximum capacitance change over temperature. Capacitance
change due to DC bias with X5R and X7R capacitors is
better than Y5V and Z5U capacitors, but can still be
CHANGE IN VALUE (%)
Output Capacitance and Transient Response
BOTH CAPACITORS ARE 16V,
1210 CASE SIZE, 10µF
–100
–50 –25
50
25
75
0
TEMPERATURE (°C)
100
125
1762 F05
Figure 5. Ceramic Capacitor Temperature Characteristics
1762fa
12
LT1762 Series
U
W
U
U
APPLICATIONS INFORMATION
significant enough to drop capacitor values below appropriate levels. Capacitor DC bias characteristics tend to
improve as component case size increases, but expected
capacitance at operating voltage should be verified.
The GND pin current can be found by examining the GND
Pin Current curves in the Typical Performance Characteristics. Power dissipation will be equal to the sum of the two
components listed above.
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
amounts of noise, especially when a ceramic capacitor is
used for noise bypassing. A ceramic capacitor produced
Figure 6’s trace in response to light tapping from a pencil.
The LT1762 series regulators have internal thermal limiting designed to protect the device during overload conditions. For continuous normal conditions, the maximum
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 ambient.
Additional heat sources mounted nearby must also be
considered.
LT1762-5
COUT = 10µF
CBYP = 0.01µf
ILOAD = 100mA
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 generated by power devices.
The following table lists thermal resistance for several
different board sizes and copper areas. All measurements
were taken in still air on 3/32" FR-4 board with one ounce
copper.
VOUT
500µV/DIV
Table 1. Measured Thermal Resistance
100ms/DIV
1762 F05
Figure 6. Noise Resulting from Tapping on a Ceramic Capacitor
Similar vibration induced behavior can masquerade as
increased output voltage noise.
Thermal Considerations
The power handling capability of the device will be limited
by the maximum rated junction temperature (125°C). The
power dissipated by the device will be made up of two
components:
1. Output current multiplied by the input/output voltage
differential: (IOUT)(VIN – VOUT), and
2. GND pin current multiplied by the input voltage:
(IGND)(VIN).
COPPER AREA
THERMAL RESISTANCE
TOPSIDE*
BACKSIDE
2500mm
2
2
1000mm
2
BOARD AREA
2500mm
2
(JUNCTION-TO-AMBIENT)
2500mm
2
110°C/W
2
115°C/W
2500mm
2500mm
225mm2
2500mm2
2500mm2
120°C/W
2
2
2500mm
2
130°C/W
2500mm
2
140°C/W
100mm
2
50mm
2500mm
2
2500mm
*Device is mounted on topside.
Calculating Junction Temperature
Example: Given an output voltage of 3.3V, an input voltage
range of 4V to 6V, an output current range of 0mA to 50mA
and a maximum ambient temperature of 50°C, what will
the maximum junction temperature be?
The power dissipated by the device will be equal to:
IOUT(MAX)(VIN(MAX) – VOUT) + IGND(VIN(MAX))
1762fa
13
LT1762 Series
U
W
U
U
APPLICATIONS INFORMATION
where,
IOUT(MAX) = 150mA
VIN(MAX) = 6V
IGND at (IOUT = 150mA, VIN = 6V) = 5mA
So,
P = 150mA(6V – 3.3V) + 5mA(6V) = 0.44W
The thermal resistance will be in the range of 110°C/W to
140°C/W depending on the copper area. So the junction
temperature rise above ambient will be approximately
equal to:
0.44W(125°C/W) = 55°C
The maximum junction temperature will then be equal to
the maximum junction temperature rise above ambient
plus the maximum ambient temperature or:
TJMAX = 50°C + 55°C = 105°C
Protection Features
The LT1762 regulators incorporate several protection
features which make them 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 devices are protected
against reverse input voltages, reverse output voltages
and reverse voltages from output to input.
Current limit protection and thermal overload protection
are intended to protect the device against current overload
conditions at the output of the device. For normal operation, the junction temperature should not exceed 125°C.
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
which can be plugged in backward.
The output of the LT1762-X can be pulled below ground
without damaging the device. If the input is left open circuit
or grounded, the output can be pulled below ground by
20V. For fixed voltage versions, the output will act like a
large resistor, typically 500kΩ or higher, limiting current
flow to less than 100µA. 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.
The ADJ pin of the adjustable device can be pulled above
or below ground by as much as 7V without damaging the
device. If the input is left open circuit or grounded, the ADJ
pin will act like an open circuit when pulled below ground
and like a large resistor (typically 100k) in series with a
diode when pulled above ground.
In situations where the ADJ pin is connected to a resistor
divider that would pull the ADJ pin above its 7V clamp
voltage 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 1.22V 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 output and
ADJ pin divided by the 5mA maximum current into the ADJ
pin yields a minimum top resistor value of 2.6k.
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 7.
When the IN pin of the LT1762-X is forced below the OUT
pin or the OUT pin is pulled above the IN pin, input current
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.
1762fa
14
LT1762 Series
U
W
U
U
APPLICATIONS INFORMATION
REVERSE OUTPUT CURRENT (µA)
100
TJ = 25°C
VIN = 0V
CURRENT FLOWS
INTO OUTPUT PIN
VOUT = VSENSE
(LT1762-2.5/LT1762-3
LT1762-3.3/LT1762-5)
VOUT = VADJ
(LT1762)
90
80
70
60
50
40
30
LT1762
LT1762-2.5
LT1762-3
20
LT1762-5
10
LT1762-3.3
0
0
1
2
3 4 5 6 7 8
OUTPUT VOLTAGE (V)
9
10
1762 F07
Figure 7. Reverse Output Current
U
PACKAGE DESCRIPTION
MS8 Package
8-Lead Plastic MSOP
(LTC DWG # 05-08-1660)
0.118 ± 0.004*
(3.00 ± 0.102)
8
7 6
5
0.118 ± 0.004**
(3.00 ± 0.102)
0.193 ± 0.006
(4.90 ± 0.15)
1
0.040 ± 0.006
(1.02 ± 0.15)
0.007
(0.18)
2 3
4
0.034 ± 0.004
(0.86 ± 0.102)
0° – 6° TYP
0.021 ± 0.006
(0.53 ± 0.015)
SEATING
PLANE 0.012
(0.30)
0.0256
REF
(0.65)
BSC
0.006 ± 0.004
(0.15 ± 0.102)
MSOP (MS8) 1098
* DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH,
PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.
INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
1762fa
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.
15
LT1762 Series
U
TYPICAL APPLICATION
Paralleling of Regulators for Higher Output Current
R1
0.1Ω
+
VIN > 3.7V
IN
OUT
+
FB
C1
10µF
C4
0.01µF
LT1762-3.3
3.3V
300mA
C2
10µF
SHDN
BYP
GND
R2
0.1Ω
IN
OUT
C5
0.01µF
LT1762
BYP
SHDN
SHDN
ADJ
GND
R3
2.2k
R4
2.2k
3
1/2 LT1490
2
R7
1.21k
8
+
–
R6
2k
1
R5
10k
4
1762 TA03
C3
0.01µF
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1120
125mA Low Dropout Regulator with 20µA IQ
Includes 2.5V Reference and Comparator
LT1121
150mA Micropower Low Dropout Regulator
30µA IQ, SOT-223 Package
LT1129
700mA Micropower Low Dropout Regulator
50µA Quiescent Current
LT1175
500mA Negative Low Dropout Micropower Regulator
45µA IQ, 0.26V Dropout Voltage, SOT-223 Package
LT1521
300mA Low Dropout Micropower Regulator with Shutdown
15µA IQ, Reverse Battery Protection
LT1529
3A Low Dropout Regulator with 50µA IQ
500mV Dropout Voltage
LT1611
Inverting 1.4MHz Switching Regulator
5V to – 5V at 150mA, Low Output Noise, SOT-23 Package
LT1613
1.4MHz Single-Cell Micropower DC/DC Converter
SOT-23 Package, Internally Compensated
LTC1627
High Efficiency Synchronous Step-Down Switching Regulator
Burst ModeTM Operation, Monolithic, 100% Duty Cycle
LT1761 Series
100mA, Low Noise, Low Dropout Micropower Regulators in SOT-23
20µA Quiescent Current, 20µVRMS Noise
LT1763 Series
500mA, Low Noise, LDO Micropower Regulators
30µA Quiescent Current, 20µVRMS Noise
Burst Mode is a trademark of Linear Technology Corporation.
1762fa
16
Linear Technology Corporation
LT 1006 REV A • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com
© LINEAR TECHNOLOGY CORPORATION 1999