LT1945IMS#TR [Linear]
IC 0.4 A DUAL SWITCHING CONTROLLER, PDSO8, PLASTIC, MSOP-10, Switching Regulator or Controller;
| 型号： | LT1945IMS#TR |
| 厂家： | 
Linear |
| 描述： | IC 0.4 A DUAL SWITCHING CONTROLLER, PDSO8, PLASTIC, MSOP-10, Switching Regulator or Controller 转换器 稳压器 开关式稳压器或控制器 电源电路 开关式控制器 光电二极管 |
| 文件： | 总8页 (文件大小：144K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
LT1945
Dual Micropower DC/DC
Converter with Positive and
Negative Outputs
U
FEATURES
DESCRIPTIO
The LT®1945 is a dual micropower DC/DC converter in a
10-pin MSOP package. Each converter is designed with a
350mA current limit and an input voltage range of 1.2V to
15V, making the LT1945 ideal for a wide variety of appli-
cations. Both converters feature a quiescent current of
only 20µA at no load, which further reduces to 0.5µA in
shutdown.Acurrentlimited,fixedoff-timecontrolscheme
conserves operating current, resulting in high efficiency
over a broad range of load current. The 36V switch allows
high voltage outputs up to ±34V to be easily generated
without the use of costly transformers. The LT1945’s low
off-time of 400ns permits the use of tiny, low profile
inductors and capacitors to minimize footprint and cost in
space-conscious portable applications.
■
Generates Well-Regulated Positive and
Negative Outputs
■
Low Quiescent Current:
20
µ
A in Active Mode (per Converter)
<1
µA in Shutdown Mode
■
■
■
■
■
Operates with VIN as Low as 1.2V
Low VCESAT Switch: 250mV at 300mA
Uses Small Surface Mount Components
High Output Voltage: Up to ±34V
Tiny 10-Pin MSOP Package
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APPLICATIO S
■
Small TFT LCD Panels
Handheld Computers
Battery Backup
Digital Cameras
■
■
, LTC and LT are registered trademarks of Linear Technology Corporation.
■
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TYPICAL APPLICATIO
Dual Output (+12V, –20V) Converter
C4
0.1µF
L1
10µH
D1
V
IN
–20V
10mA
Efficiency at VIN = 3.6V
2.7V
TO 5V
8
10
90
100pF
365k
V
SW1
IN
85
2
4
1
5
+12V OUTPUT
SHDN1
NFB1
80
C1
4.7µF
C2
1µF
LT1945
D2
–20V OUTPUT
75
70
65
60
SHDN2
FB2
24.9k
GND PGND PGND SW2
3
7
9
6
115k
55
C3
1µF
4.7pF
D3
1M
50
L2
10µH
0.1
1
10
100
12V
20mA
1945 TA01
LOAD CURRENT (mA)
1945 TA01a
C1: TAIYO YUDEN JMK212BJ475
C2, C3: TAIYO YUDEN TMK316BJ105
C4: TAIYO YUDEN EMK107BJ104
D1, D2, D3: ZETEX ZHCS400
L1, L2: MURATA LQH3C100
1945f
1
LT1945
W W
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ABSOLUTE AXI U RATI GS
PACKAGE/ORDER I FOR ATIO
(Note 1)
ORDER PART
NUMBER
TOP VIEW
VIN, SHDN1, SHDN2 Voltage ................................... 15V
SW1, SW2 Voltage .................................................. 36V
NFB1 Voltage ........................................................... –3V
FB2 Voltage ...............................................................VIN
Current into NFB1 Pin ........................................... –1mA
Current into FB2 Pin .............................................. 1mA
Junction Temperature........................................... 125°C
Operating Temperature Range (Note 2) .. –40°C to 85°C
Storage Temperature Range ................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
NFB1
SHDN1
GND
SHDN2
FB2
1
2
3
4
5
10 SW1
9
8
7
6
PGND
LT1945EMS
V
IN
PGND
SW2
MS PACKAGE
10-LEAD PLASTIC MSOP
MS PART MARKING
LTTS
TJMAX = 125°C, θJA = 160°C/W
Consult LTC Marketing for parts specified with wider operating temperature ranges.
The ● denotes the specifications which apply over the full operating
ELECTRICAL CHARACTERISTICS
temperature range, otherwise specifications are at TA = 25°C. VIN = 1.2V, VSHDN = 1.2V unless otherwise noted.
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Minimum Input Voltage
Quiescent Current, (per Converter)
1.2
V
Not Switching
20
30
1
µA
µA
V
= 0V
SHDN
NFB1 Comparator Trip Point
●
●
–1.205
1.205
–1.23
1.23
8
–1.255
1.255
V
V
FB2 Comparator Trip Point
FB Comparator Hysteresis
mV
%/V
µA
NFB1, FB2 Voltage Line Regulation
NFB1 Pin Bias Current (Note 3)
FB2 Pin Bias Current (Note 4)
Switch Off Time, Switcher 1 (Note 5)
Switch Off Time, Switcher 2 (Note 5)
1.2V < V < 12V
0.05
2
0.1
2.9
80
IN
V
V
= –1.23V
●
●
1.3
NFB1
= 1.23V
30
nA
FB2
400
ns
V
V
> 1V
< 0.6V
400
1.5
ns
µs
FB2
FB2
Switch V
I
= 300mA
SW
250
350
350
400
mV
mA
CESAT
Switch Current Limit
SHDN Pin Current
250
0.9
V
V
= 1.2V
= 5V
2
8
3
12
µA
µA
SHDN
SHDN
SHDN Input Voltage High
SHDN Input Voltage Low
Switch Leakage Current
V
V
0.25
5
Switch Off, V = 5V
0.01
µA
SW
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
temperature range are assured by design, characterization and correlation
with statistical process controls.
Note 2: The LT1945 is guaranteed to meet performance specifications
from 0°C to 70°C. Specifications over the –40°C to 85°C operating
Note 3: Bias current flows out of the NFB1 pin.
Note 4: Bias current flows into the FB2 pin.
Note 5: See Figure 1 for Switcher 1 and Switcher 2 locations.
1945f
2
LT1945
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TYPICAL PERFOR A CE CHARACTERISTICS
Switch Saturation Voltage
(VCESAT
FB2 Pin Voltage and
Bias Current
NFB1 Pin Voltage and
Bias Current
)
0.60
0.55
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
5
4
3
2
1
0
1.25
1.24
1.23
1.22
1.21
1.20
50
40
30
20
10
0
–1.25
–1.24
–1.23
–1.22
–1.21
–1.20
VOLTAGE
VOLTAGE
CURRENT
I
I
= 500mA
= 300mA
SWITCH
SWITCH
CURRENT
–50
–25
0
25
50
75
100
–50
–25
0
25
50
75
100
–50
–25
0
25
50
75
100
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
1945 G03
1945 G01
1945 G02
Switch Off Time
Switch Current Limit
Quiescent Current
550
500
450
400
350
300
250
400
350
300
250
200
150
100
50
25
23
21
19
17
15
V
= 12V
IN
V
= 1.23V
FB
NOT SWITCHING
V
= 1.2V
IN
V
= 1.2V
IN
V
= 12V
IN
V
= 12V
IN
V
= 1.2V
50
IN
0
–50
–25
0
25
50
75
100
–50
–25
0
25
50
75
100
–50
–25
0
25
75
100
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
1945 G04
1945 G05
1945 G06
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PI FU CTIO S
NFB1 (Pin 1): Feedback Pin for Switcher 1. Set the output
SW2 (Pin 6): Switch Pin for Switcher 2. This is the
collector of the internal NPN power switch. Minimize the
metal trace area connected to the pin to minimize EMI.
voltage by selecting values for R1 and R2.
SHDN1 (Pin 2): Shutdown Pin for Switcher 1. Tie this pin
to 0.9V or higher to enable device. Tie below 0.25V to turn
it off.
PGND (Pins 7, 9): Power Ground. Tie these pins directly
to the local ground plane. Both pins must be tied.
GND (Pin 3): Ground. Tie this pin directly to the local
ground plane.
VIN (Pin 8): Input Supply Pin. Bypass this pin with a
capacitor as close to the device as possible.
SHDN2 (Pin 4): Shutdown Pin for Switcher 2. Tie this pin
to 0.9V or higher to enable device. Tie below 0.25V to turn
it off.
SW1 (Pin 10): Switch Pin for Switcher 1. This is the
collector of the internal NPN power switch. Minimize the
metal trace area connected to the pin to minimize EMI.
FB2 (Pin 5): Feedback Pin for Switcher 2. Set the output
voltage by selecting values for R1B and R2B.
1945f
3
LT1945
W
BLOCK DIAGRA
C3
D2
L1
L2
L3
V
IN
V
V
V
IN
OUT1
OUT2
C4
D1
C2
C1
V
IN
SHDN1
SW1
SW2
SHDN2
8
2
10
6
4
V
IN
R5
80k
R6
80k
R6B
40k
R5B
40k
A1
A1B
+
+
ENABLE
ENABLE
V
OUT2
R1B
–
–
Q1B
(EXTERNAL)
FB2
Q1
400ns
400ns
Q2
Q2B
X10
5
Q3
Q3B
ONE-SHOT
ONE-SHOT
X10
R2B
(EXTERNAL)
DRIVER
DRIVER
R3
60k
R3B
30k
RESET
RESET
+
+
–
R4
280k
R4B
140k
0.12Ω
0.12Ω
V
OUT1
–
42mV
42mV
A2
A2B
R1
(EXTERNAL)
NFB1
SWITCHER 1
SWITCHER 2
1
R2
PGND PGND
GND
3
9
7
(EXTERNAL)
1945 BD
Figure 1. LT1945 Block Diagram
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OPERATIO
The LT1945 uses a constant off-time control scheme to
provide high efficiencies over a wide range of output
current. Operation can be best understood by referring to
theblockdiagraminFigure1.Q1andQ2alongwithR3and
R4 form a bandgap reference used to regulate the output
voltage. When the voltage at the NFB1 pin is slightly below
–1.23V, comparator A1 disables most of the internal
circuitry. Output current is then provided by capacitor C2,
which slowly discharges until the voltage at the NFB1 pin
goes above the hysteresis point of A1 (typical hysteresis
at the NFB1 pin is 8mV). A1 then enables the internal
circuitry, turns on power switch Q3, and the current in
inductors L1 and L2 begins ramping up. Once the switch
current reaches 350mA, comparator A2 resets the one-
shot, which turns off Q3 for 400ns. L2 continues to deliver
current to the output while Q3 is off. Q3 turns on again and
the inductor currents ramp back up to 350mA, then A2
againresetstheone-shot. Thisswitchingactioncontinues
until the output voltage is charged up (until the NFB1 pin
reaches –1.23V), then A1 turns off the internal circuitry
and the cycle repeats.
The second switching regulator is a step-up converter
(which generates a positive output) but the basic opera-
tion is the same.The LT1945 contains additional circuitry
to provide protection during start-up and under short-
circuit conditions. When the FB2 pin voltage is less than
approximately 600mV, the switch off-time is increased to
1.5µs and the current limit is reduced to around 250mA
(70% of its normal value). This reduces the average
inductorcurrentandhelpsminimizethepowerdissipation
in the power switch and in the external inductor and diode.
1945f
4
LT1945
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APPLICATIO S I FOR ATIO
Choosing an Inductor
in the above equation. For most regulators with output
voltages below 7V, a 4.7µH inductor is the best choice,
even though the equation above might specify a smaller
value. This is due to the inductor current overshoot that
occurs when very small inductor values are used (see
Current Limit Overshoot section).
Several recommended inductors that work well with the
LT1945arelistedinTable1,althoughtherearemanyother
manufacturers and devices that can be used. Consult each
manufacturer for more detailed information and for their
entire selection of related parts. Many different sizes and
shapesareavailable. Usetheequationsandrecommenda-
tionsinthenextfewsectionstofindthecorrectinductance
value for your design.
For higher output voltages, the formula above will give
large inductance values. For a 2V to 20V converter (typical
LCD Bias application), a 21µH inductor is called for with
the above equation, but a 10µH inductor could be used
without excessive reduction in maximum output current.
Table 1. Recommended Inductors
PART
VALUE (µH)
MAX DCR (
Ω
)
VENDOR
LQH3C4R7
LQH3C100
LQH3C220
4.7
10
22
0.26
0.30
0.92
Murata
(714) 852-2001
www.murata.com
Inductor Selection—SEPIC Regulator
The formula below calculates the approximate inductor
value to be used for a SEPIC regulator using the LT1945.
As for the boost inductor selection, a larger or smaller
value can be used.
CD43-4R7
CD43-100
CDRH4D18-4R7
CDRH4D18-100
4.7
10
4.7
10
0.11
0.18
0.16
0.20
Sumida
(847) 956-0666
www.sumida.com
DO1608-472
DO1608-103
DO1608-223
4.7
10
22
0.09
0.16
0.37
Coilcraft
(847) 639-6400
www.coilcraft.com
VOUT + VD
L = 2
tOFF
ILIM
Inductor Selection—Boost Regulator
Inductor Selection—Inverting Regulator
The formula below calculates the appropriate inductor
valuetobeusedforaboostregulatorusingtheLT1945(or
at least provides a good starting point). This value pro-
vides a good tradeoff in inductor size and system perfor-
mance. Pick a standard inductor close to this value. A
larger value can be used to slightly increase the available
output current, but limit it to around twice the value
calculated below, as too large of an inductance will in-
crease the output voltage ripple without providing much
additional output current. A smaller value can be used
(especially for systems with output voltages greater than
12V) to give a smaller physical size. Inductance can be
calculated as:
The formula below calculates the appropriate inductor
value to be used for an inverting regulator using the
LT1945 (or at least provides a good starting point). This
value provides a good tradeoff in inductor size and system
performance. Pick a standard inductor close to this value
(both inductors should be the same value). A larger value
can be used to slightly increase the available output
current, but limit it to around twice the value calculated
below, as too large of an inductance will increase the
output voltage ripple without providing much additional
output current. A smaller value can be used (especially for
systems with output voltages greater than 12V) to give a
smaller physical size. Inductance can be calculated as:
V
OUT − V
) + VD
IN MIN
(
L =
tOFF
VOUT + VD
ILIM
L = 2
tOFF
ILIM
where VD = 0.4V (Schottky diode voltage), ILIM = 350mA
and tOFF = 400ns; for designs with varying VIN such as
battery powered applications, use the minimum VIN value
where VD = 0.4V (Schottky diode voltage), ILIM = 350mA
and tOFF = 400ns.
1945f
5
LT1945
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APPLICATIO S I FOR ATIO
For higher output voltages, the formula above will give
large inductance values. For a 2V to 20V converter (typical
LCD bias application), a 47µH inductor is called for with
the above equation, but a 10µH or 22µH inductor could be
used without excessive reduction in maximum output
current.
high input voltages and smaller inductor values. This
overshootcanbebeneficialasithelpsincreasetheamount
of available output current for smaller inductor values.
This will be the peak current seen by the inductor (and the
diode) during normal operation. For designs using small
inductance values (especially at input voltages greater
than 5V), the current limit overshoot can be quite high.
Although it is internally current limited to 350mA, the
power switch of the LT1945 can handle larger currents
without problem, but the overall efficiency will suffer. Best
results will be obtained when IPEAK is kept below 700mA
for the LT1945.
Inductor Selection—Inverting Charge Pump Regulator
For the inverting regulator, the voltage seen by the internal
power switch is equal to the sum of the absolute value of
the input and output voltages, so that generating high
output voltages from a high input voltage source will often
exceed the 36V maximum switch rating. For instance, a
12V to –30V converter using the inverting topology would
generate 42V on the SW pin, exceeding its maximum
rating. For this application, an inverting charge pump is
the best topology.
Capacitor Selection
LowESR(EquivalentSeriesResistance)capacitorsshould
beusedattheoutputtominimizetheoutputripplevoltage.
X5R or X7R multilayer ceramic capacitors are the best
choice, as they have a very low ESR and are available in
verysmallpackages.Y5Vceramicsarenotrecommended.
Their small size makes them a good companion to the
LT1945’s MS10 package. Solid tantalum capacitors (like
the AVX TPS, Sprague 593D families) or OS-CON capaci-
tors can be used, but they will occupy more board area
than a ceramic and will have a higher ESR. Always use a
capacitor with a sufficient voltage rating.
The formula below calculates the approximate inductor
value to be used for an inverting charge pump regulator
using the LT1945. As for the boost inductor selection, a
larger or smaller value can be used. For designs with
varying VIN such as battery powered applications, use the
minimum VIN value in the equation below.
VOUT − V
) + VD
IN MIN
(
L =
tOFF
Ceramic capacitors also make a good choice for the input
decoupling capacitor, which should be placed as close as
possible to the LT1945. A 4.7µF input capacitor is suffi-
cient for most applications. Table 2 shows a list of several
capacitor manufacturers. Consult the manufacturers for
more detailed information and for their entire selection of
related parts.
ILIM
Current Limit Overshoot
For the constant off-time control scheme of the LT1945,
thepowerswitchisturnedoffonlyafterthe350mAcurrent
limit is reached. There is a 100ns delay between the time
when the current limit is reached and when the switch
actually turns off. During this delay, the inductor current
exceeds the current limit by a small amount. The peak
inductor current can be calculated by:
Table 2. Recommended Capacitors
CAPACITOR TYPE
VENDOR
Ceramic
Taiyo Yuden
(408) 573-4150
www.t-yuden.com
Ceramic
Ceramic
AVX
V
IN(MAX) − VSAT
(803) 448-9411
www.avxcorp.com
IPEAK = ILIM
+
100ns
L
Murata
(714) 852-2001
www.murata.com
Where VSAT = 0.25V (switch saturation voltage). The
current overshoot will be most evident for regulators with
1945f
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LT1945
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APPLICATIO S I FOR ATIO
Setting the Output Voltages
fast switching speed, are the best match for the LT1945.
TheMotorolaMBR0520,MBR0530,orMBR0540canalso
be used. Many different manufacturers make equivalent
parts, but make sure that the component is rated to handle
at least 0.35A.
Set the output voltage for Switcher 1 (negative output
voltage ) by choosing the appropriate values for feedback
resistors R1 and R2.
VOUT –1.23V
Lowering Output Voltage Ripple
R1=
Using low ESR capacitors will help minimize the output
ripple voltage, but proper selection of the inductor and the
output capacitor also plays a big role. The LT1945 pro-
vides energy to the load in bursts by ramping up the
inductor current, then delivering that current to the load.
If too large of an inductor value or too small of a capacitor
value is used, the output ripple voltage will increase
because the capacitor will be slightly overcharged each
burst cycle. To reduce the output ripple, increase the
outputcapacitorvalueoradda4.7pFfeed-forwardcapaci-
tor in the feedback network of the LT1945 (see the circuits
in the Typical Applications section). Adding this small,
inexpensive 4.7pF capacitor will greatly reduce the output
voltage ripple.
1.23V
R2
+ 2•10−6
(
)
Set the output voltage for Switcher 2 (positive output
voltage) by choosing the appropriate values for feedback
resistors R1B and R2B (see Figure 1).
VOUT
1.23V
R1B = R2B
−1
Diode Selection
For most LT1945 applications, the Zetex ZHCS400 sur-
face mount Schottky diode (0.4A, 40V) is an ideal choice.
Schottky diodes, with their low forward voltage drop and
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PACKAGE DESCRIPTIO
MS Package
10-Lead Plastic MSOP
(Reference LTC DWG # 05-08-1661)
3.00 ± 0.102
(.118 ± .004)
(NOTE 3)
0.889 ± 0.127
(.035 ± .005)
0.497 ± 0.076
(.0196 ± .003)
REF
10 9
8
7 6
5.23
(.206)
MIN
3.00 ± 0.102
(.118 ± .004)
NOTE 4
3.2 – 3.45
(.126 – .136)
4.88 ± 0.10
(.192 ± .004)
DETAIL “A”
0.254
(.010)
0° – 6° TYP
GAUGE PLANE
0.50
(.0197)
BSC
0.305 ± 0.038
(.0120 ± .0015)
TYP
1
2
3
4 5
0.53 ± 0.01
(.021 ± .006)
RECOMMENDED SOLDER PAD LAYOUT
0.86
(.034)
REF
1.10
(.043)
MAX
DETAIL “A”
0.18
(.007)
SEATING
PLANE
NOTE:
0.17 – 0.27
(.007 – .011)
0.13 ± 0.05
(.005 ± .002)
MSOP (MS) 0402
1. DIMENSIONS IN MILLIMETER/(INCH)
2. DRAWING NOT TO SCALE
0.50
(.0197)
TYP
3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS.
MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") PER SIDE
4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.
INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006") PER SIDE
5. LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX
1945f
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 represen-
tationthattheinterconnectionofitscircuitsasdescribedhereinwillnotinfringeonexistingpatentrights.
7
LT1945
U
TYPICAL APPLICATIO
Dual Output (±32V) Converter
C4
0.1µF
L1
10µH
D1
V
IN
–32V
5mA
2.7V
Efficiency at VIN = 3.6V
TO 5V
8
10
80
75
70
65
60
55
50
100pF
604k
V
SW1
IN
2
4
1
5
+32V OUTPUT
SHDN1
NFB1
C1
4.7µF
C2
1µF
LT1945
D2
–32V OUTPUT
SHDN2
FB2
24.9k
GND PGND PGND SW2
3
7
9
6
80.6k
C3
4.7pF
D3
2M
1µF
L2
10µH
0.1
1
10
32V
LOAD CURRENT (mA)
5mA
1945 TA02
1945 TA02a
C1: TAIYO YUDEN JMK212BJ475
C2, C3: TAIYO YUDEN GMK316BJ105 (408)573-4150
(408)573-4150
C4: TAIYO YUDEN UMK212BJ104
D1, D2, D3: ZETEX ZHCS400
L1, L2: MURATA LQH3C100
(408)573-4150
(631)543-7100
(814)237-1431
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
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V
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Q SD
SW
IN
OUT
OUT
ThinSOT Package
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IN
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LT1940
LT1944
LT1944-1
Dual Output 1.4A (I ), Constant 1.1MHz, High Efficiency
Step-Down DC/DC Converter
V
= 3V to 25V, V
= 1.2V, I = 2.5mA, I = <1µA,
OUT Q SD
OUT
IN
TSSOP-16E Package
Dual Output 350mA I , Constant Off-Time, High Efficiency
V
V
V
= 1.2V to 15V, V
= 1.2V to 15V, V
= 1.5V to 12V, V
= 34V, I = 20µA, I = <1µA, MS Package
Q SD
SW
IN
IN
IN
OUT
OUT
OUT
OUT
Step-Up DC/DC Converter
Dual Output 150mA I , Constant Off-Time, High Efficiency
= 34V, I = 20µA, I = <1µA, MS Package
Q SD
SW
Step-Up DC/DC Converter
LT1949/LT1949-1 550mA I , 600kHz/1.1MHz, High Efficiency
= 28V, I = 4.5mA, I = <25µA,
Q SD
SW
Step-Up DC/DC Converter
S8, MS8 Packages
LTC3400/LTC3400B 600mA I , 1.2MHz, Synchronous Step-Up DC/DC Converter
V
= 0.85V to 5V, V
= 5V, I = 19µA/300µA, I = <1µA,
Q SD
SW
IN
ThinSOT Package
LTC3401
LTC3402
LTC3423
1A I , 3MHz, Synchronous Step-Up DC/DC Converter
V
V
V
= 0.5V to 5V, V
= 0.5V to 5V, V
= 0.5V to 5V, V
= 6V, I = 38µA, I = <1µA, MS Package
Q SD
SW
IN
IN
IN
OUT
OUT
OUT
2A I , 3MHz, Synchronous Step-Up DC/DC Converter
= 6V, I = 38µA, I = <1µA, MS Package
Q SD
SW
1A I , 3MHz, Low V , Synchronous Step-Up
= 6V, I = 38µA, I = <1µA, MS Package
Q SD
SW
OUT
DC/DC Converter
LTC3424
2A I , 3MHz, Low V , Synchronous Step-Up
DC/DC Converter
V
= 0.5V to 5V, V
= 6V, I = 38µA, I = <1µA, MS Package
OUT Q SD
SW
OUT
IN
1945f
LT/TP 0802 2K • PRINTED IN USA
LinearTechnology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
8
●
●
LINEAR TECHNOLOGY CORPORATION 2001
(408) 432-1900 FAX: (408) 434-0507 www.linear.com
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