LTC3400/LTC3400B
600mA, 1.2MHz Micropower
Synchronous Boost Converter
in ThinSOT
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FEATURES
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DESCRIPTIO
The LTC®3400/LTC3400B are synchronous, fixed frequency, step-up DC/DC converters delivering high efficiency in a 6-lead ThinSOT™ package. Capable of supplying
3.3V at 100mA from a single AA cell input, the devices
contain an internal NMOS switch and PMOS synchronous
rectifier.
Up to 92% Efficiency
Generates 3.3V at 100mA from a Single AA Cell
Low Start-Up Voltage: 0.85V
1.2MHz Fixed Frequency Switching
Internal Synchronous Rectifier
2.5V to 5V Output Range
Automatic Burst Mode® Operation (LTC3400)
Continuous Switching at Light Loads (LTC3400B)
Logic Controlled Shutdown (< 1µA)
Antiringing Control Minimizes EMI
Tiny External Components
Low Profile (1mm) SOT-23 Package
A switching frequency of 1.2MHz minimizes solution
footprint by allowing the use of tiny, low profile inductors
and ceramic capacitors. The current mode PWM design is
internally compensated, reducing external parts count.
The LTC3400 features automatic shifting to power saving
Burst Mode operation at light loads, while the LTC3400B
features continuous switching at light loads. Antiringing
control circuitry reduces EMI concerns by damping the
inductor in discontinuous mode, and the devices feature
low shutdown current of under 1µA.
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APPLICATIO S
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Pagers
MP3 Players
Digital Cameras
LCD Bias Supplies
Handheld Instruments
Wireless Handsets
GPS Receivers
Both devices are available in the low profile (1mm)
SOT-23 package.
, LTC, LT and Burst Mode are registered trademarks of Linear Technology Corporation.
ThinSOT is a trademark of Linear Technology Corporation.
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TYPICAL APPLICATIO
Efficiency
L1
4.7µH
SINGLE
AA CELL
C1
4.7µF
VIN = 2.4V
1
6
90
SW
VOUT
VIN
5
LTC3400
OFF ON
4
FB
SHDN
GND
2
C1, C2: TAIYO-YUDEN X5R EMK316BJ475ML
L1: COILCRAFT DO160C-472
3
R1
1.02M
1%
R2
604k
1%
VOUT
3.3V
100mA
C2
4.7µF
3400 F01
EFFICIENCY (%)
+
100
VIN = 1.5V
80
70
60
50
FIGURE 1 CIRCUIT
WITH OPTIONAL SCHOTTKY DIODE
(SEE APPLICATIONS INFORMATION)
40
0.1
Figure 1. Single Cell to 3.3V Synchronous Boost Converter
1
10
100
LOAD CURRENT (mA)
1000
3400 F01a
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LTC3400/LTC3400B
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AXI U
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ABSOLUTE
RATI GS
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PACKAGE/ORDER I FOR ATIO
(Note 1)
VIN Voltage ................................................. – 0.3V to 6V
SW Voltage ................................................. – 0.3V to 6V
SHDN, FB Voltage ....................................... – 0.3V to 6V
VOUT ........................................................... – 0.3V to 6V
Operating Temperature Range (Note 2) .. – 30°C to 85°C
Storage Temperature Range ................... – 65°C to 125°
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
TOP VIEW
SW 1
GND 2
FB 3
6 VIN
LTC3400ES6
LTC3400BES6
5 VOUT
4 SHDN
S6 PART MARKING
S6 PACKAGE
6-LEAD PLASTIC SOT-23
LTWK
LTUN
TJMAX = 125°C, θJC = 102°C/W
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VIN = 1.2V, VOUT = 3.3V, unless otherwise specified.
PARAMETER
CONDITIONS
Minimum Start-Up Voltage
ILOAD = 1mA
Minimum Operating Voltage
SHDN = VIN (Note 4)
MIN
Output Voltage Adjust Range
TYP
MAX
0.85
1
0.5
0.65
V
5
V
1.268
V
2.5
Feedback Voltage
●
1.192
1.23
UNITS
V
Feedback Input Current
VFB = 1.25V (Note 3)
1
Quiescent Current (Burst Mode Operation)
VFB = 1.4V (Note 5), LTC3400 Only
19
30
µA
Quiescent Current (Shutdown)
VSHDN = 0V, Not Including Switch Leakage
0.01
1
µA
Quiescent Current (Active)
Measured On VOUT
300
500
µA
NMOS Switch Leakage
VSW = 5V
0.1
5
µA
PMOS Switch Leakage
VSW = 0V
0.1
5
µA
NMOS Switch On Resistance
VOUT = 3.3V
VOUT = 5V
0.35
0.20
Ω
Ω
PMOS Switch On Resistance
VOUT = 3.3V
VOUT = 5V
0.45
0.30
Ω
Ω
850
mA
NMOS Current Limit
600
nA
Burst Mode Operation Current Threshold
LTC3400 Only (Note 3)
3
mA
Current Limit Delay to Output
(Note 3)
40
ns
Max Duty Cycle
VFB = 1.15V
●
80
87
●
0.95
0.85
1.2
1.2
Switching Frequency
SHDN Input High
MHz
MHz
0.35
V
1
µA
1
V
SHDN Input Low
SHDN Input Current
%
1.5
1.5
VSHDN = 5.5V
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The LTC3400E/LTC3400BE are guaranteed to meet performance
specifications from 0°C to 70°C. Specifications over the – 30°C to 85°C
operating temperature range are assured by design, characterization and
correlation with statistical process controls.
0.01
Note 3: Specification is guaranteed by design and not 100% tested in
production.
Note 4: Minimum VIN operation after start-up is only limited by the
battery’s ability to provide the necessary power as it enters a deeply
discharged state.
Note 5: Burst Mode operation IQ is measured at VOUT. Multiply this value
by VOUT/VIN to get the equivalent input (battery) current.
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LTC3400/LTC3400B
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TYPICAL PERFOR A CE CHARACTERISTICS
Output Load Burst Mode Threshold
vs VIN
Minimum Start-Up Voltage
vs Load Current
VOUT vs Temperature
3.36
L = 4.7µH
TA = 25°C
1.4
FIGURE 1 CIRCUIT
IO = 10mA
1.3
START-UP VOLTAGE (V)
VOUT = 3.3V
VOUT = 5V
3.32
VOUT (V)
OUTPUT CURRENT (mA)
3.34
20
3.30
10
3.28
0.9
1.5
2.1
2.7
VIN (V)
3.3
3.9
3.24
–60
4.5
1.1
1.0
0.8
–30
0
30
60
TEMPERATURE (°C)
90
120
0.1
1
10
IOUT (mA) CURRENT SOURCE LOAD
3400 G02
3400 G01
100
3400 G03
Normalized Oscillator Frequency
vs Temperature
No Load Battery Current vs VBATT
1000
1.2
0.9
3.26
0
TA = 25°C
SW Pin Antiringing Operation
1.01
VOUT = 3.3V
TA = 25°C
NORMALIZED FREQUENCY
BATTERY CURRENT (µA)
1.00
100
0.99
VSW
1V/DIV
0.98
0.97
0V
0.96
10
0.9
1.2
1.5 1.8 2.1 2.4
BATTERY VOLTAGE (V)
2.7
0.95
–50 –30
3.0
30
50
–10 10
TEMPERATURE (°C)
3400 G04
Fixed Frequency and Burst Mode
Operation
VSW
1V/DIV
3400 G07
3400 G06
VOUT Transient Response
VOUT(AC)
100mV/DIV
VOUT(AC)
100mV/DIV
60mA
100mA
IOUT
40mA
IOUT
0V
100ns/DIV
90
100ns/DIV
3400 G05
SW Pin Fixed Frequency,
Continuous Inductor Current
Operation
VIN = 1.3V
VOUT = 3.3V
IOUT = 50mA
L = 6.8µH
COUT = 4.7µF
70
VIN = 1.3V
VOUT = 3.3V
IOUT = 10mA
L = 6.8µH
COUT = 4.7µF
10µA
10ms/DIV
VIN = 1.3V
VOUT = 3.3V
IOUT = 60mA TO 10µA
L = 6.8µH
COUT = 4.7µF
3400 G08
100µs/DIV
VIN = 1.3V
VOUT = 3.3V
IOUT = 40mA TO 100mA
L = 6.8µH
COUT = 4.7µF
3400 G09
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LTC3400/LTC3400B
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SHDN = Low: Shutdown, quiescent current < 1µA.
100Ω connected between SW and VIN.
SW (Pin 1): Switch Pin. Connect inductor between SW
and VIN. Optional Schottky diode is connected between
SW and VOUT. Keep these PCB trace lengths as short and
wide as possible to reduce EMI and voltage overshoot. If
the inductor current falls to zero, or SHDN is low, an
internal 100Ω antiringing switch is connected from SW to
VIN to minimize EMI.
Typically, SHDN should be connected to VIN through a 1M
pull-up resistor.
VOUT (Pin 5): Output Voltage Sense Input and Drain of the
Internal Synchronous Rectifier MOSFET. Bias is derived
from VOUT. PCB trace length from VOUT to the output filter
capacitor(s) should be as short and wide as possible. VOUT
is held at VIN – 0.6V in shutdown due to the body diode of
the internal PMOS.
GND (Pin 2): Signal and Power Ground. Provide a short
direct PCB path between GND and the (–) side of the output
capacitor(s).
FB (Pin 3): Feedback Input to the gm Error Amplifier.
Connect resistor divider tap to this pin. The output voltage
can be adjusted from 2.5V to 5V by:
VIN (Pin 6): Battery Input Voltage. The device gets its
start-up bias from VIN. Once VOUT exceeds VIN, bias
comes from VOUT. Thus, once started, operation is completely independent from VIN. Operation is only limited by
the output power level and the battery’s internal series
resistance.
VOUT = 1.23V • [1 + (R1/R2)]
SHDN (Pin 4): Logic Controlled Shutdown Input.
SHDN = High: Normal free running operation, 1.2MHz
typical operating frequency.
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BLOCK DIAGRA
L1
4.7µH
SINGLE
CELL
INPUT
CIN
1µF
6 VIN
1 SW
OPTIONAL
SCHOTTKY
+
+
VOUT
GOOD
–
START-UP
OSC
A
2.3V
A/B
MUX
5
SYNC
DRIVE
CONTROL
PWM
CONTROL
RAMP
GEN
1.2MHz
3.3V
OUTPUT
VOUT
0.45Ω
B
Σ
SLOPE
COMP
0.35Ω
CURRENT
SENSE
R1
1.02M
1%
(EXTERNAL)
CFF
(OPTIONAL)
PWM
COMPARATOR
–
–
+
FB
–
SLEEP
Burst Mode
OPERATION
CONTROL
CC
150pF
SHDN
4
SHUTDOWN
CONTROL
SHUTDOWN
+
RC
80k
gm
ERROR
AMP
CP2
2.5pF
COUT
4.7µF
3
1.23V
REF
R2
604k
1%
(EXTERNAL)
2 GND
3400 BD
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LTC3400/LTC3400B
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OPERATIO
The LTC3400/LTC3400B are 1.2MHz, synchronous boost
converters housed in a 6-lead ThinSOT package. Able to
operate from an input voltage below 1V, the devices
feature fixed frequency, current mode PWM control for
exceptional line and load regulation. With its low RDS(ON)
and gate charge internal MOSFET switches, the devices
maintain high efficiency over a wide range of load current.
Detailed descriptions of the three distinct operating modes
follow. Operation can be best understood by referring to
the Block Diagram.
Low Voltage Start-Up
The LTC3400/LTC3400B will start up at a typical VIN voltage of 0.85V or higher. The low voltage start-up circuitry
controls the internal NMOS switch up to a maximum peak
inductor current of 850mA (typ), with an approximate
1.5µs off-time during start-up, allowing the devices to
start up into an output load. Once VOUT exceeds 2.3V, the
start-up circuitry is disabled and normal fixed frequency
PWM operation is initiated. In this mode, the LTC3400/
LTC3400B operate independent of VIN, allowing extended
operating time as the battery can droop to several tenths
of a volt without affecting output voltage regulation. The
limiting factor for the application becomes the ability of the
battery to supply sufficient energy to the output.
Low Noise Fixed Frequency Operation
Oscillator: The frequency of operation is internally set to
1.2MHz.
Error Amp: The error amplifier is an internally compensated
transconductance type (current output) with a transconductance (gm) = 33 microsiemens. The internal 1.23V reference
voltage is compared to the voltage at the FB pin to generate
an error signal at the output of the error amplifier. A voltage divider from VOUT to ground programs the output
voltage via FB from 2.5V to 5V using the equation:
VOUT = 1.23V • [1 + (R1/R2)]
Current Sensing: A signal representing NMOS switch
current is summed with the slope compensator. The
summed signal is compared to the error amplifier output
to provide a peak current control command for the PWM.
Peak switch current is limited to approximately 850mA
independent of input or output voltage. The current signal
is blanked for 40ns to enhance noise rejection.
Zero Current Comparator: The zero current comparator
monitors the inductor current to the output and shuts off
the synchronous rectifier once this current reduces to approximately 20mA. This prevents the inductor current from
reversing in polarity improving efficiency at light loads.
Antiringing Control: The antiringing control circuitry prevents high frequency ringing of the SW pin as the inductor
current goes to zero by damping the resonant circuit
formed by L and CSW (capacitance on SW pin).
Burst Mode Operation
Portable devices frequently spend extended time in low
power or standby mode, only switching to high power
drain when specific functions are enabled. In order to
improve battery life in these types of products, high power
converter efficiency needs to be maintained over a wide
output power range. In addition to its high efficiency at
moderate and heavy loads, the LTC3400 includes automatic Burst Mode operation that improves efficiency of
the power converter at light loads. Burst mode operation
is initiated if the output load current falls below an
internally programmed threshold (see Typical Performance graph, Output Load Burst Mode Threshold vs V IN).
Once initiated, the Burst Mode operation circuitry shuts
down most of the device, only keeping alive the circuitry
required to monitor the output voltage. This is referred to
as the sleep state. In sleep, the LTC3400 draws only 19µA
from the output capacitor, greatly enhancing efficiency.
When the output voltage has drooped approximately 1%
from nominal, the LTC3400 wakes up and commences
normal PWM operation. The output capacitor recharges
and causes the LTC3400 to reenter sleep if the output load
remains less than the sleep threshold. The frequency of
this intermittent PWM or burst operation is proportional to
load current; that is, as the load current drops further
below the burst threshold, the LTC3400 turns on less
frequently. When the load current increases above the
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LTC3400/LTC3400B
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OPERATIO
burst threshold, the LTC3400 will resume continuous
PWM operation seamlessly. Referring to the Block Diagram, an optional capacitor (CFF) between VOUT and FB in
some circumstances can reduce the peak-to-peak VOUT
ripple and input quiescent current during Burst Mode
operation. Typical values for CFF range from 15pF to
220pF. The LTC3400B does not use Burst Mode operation
and features continous operation at light loads, eliminating low frequency output voltage ripple at the expense of
light load efficiency.
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APPLICATIO S I FOR ATIO
PCB LAYOUT GUIDELINES
The high speed operation of the LTC3400/LTC3400B
demands careful attention to board layout. You will not get
advertised performance with careless layout. Figure 2
shows the recommended component placement. A large
ground pin copper area will help to lower the chip temperature. A multilayer board with a separate ground plane is
ideal, but not absolutely necessary.
of inductance will allow greater output current capability
by reducing the inductor ripple current. Increasing the
inductance above 10µH will increase size while providing
little improvement in output current capability.
The approximate output current capability of the LTC3400/
LTC3400B versus inductance value is given in the equation below and illustrated graphically in Figure 3.
VIN =1.2V
180
VIN
1
SW
2
GND VOUT 5
3
OUTPUT CURRENT (mA)
(OPTIONAL)
VIN 6
FB SHDN 4
SHDN
VOUT = 3V
VOUT = 3.3V
160
VOUT = 3.6V
140
120
VOUT = 5V
110
80
60
VOUT
3
5
7
9 11 13 15 17 19 21 23
INDUCTANCE (µH)
3400 F02
3400 F03
RECOMMENDED COMPONENT PLACEMENT. TRACES
CARRYING HIGH CURRENT ARE DIRECT. TRACE AREA AT
FB PIN IS SMALL. LEAD LENGTH TO BATTERY IS SHORT
Figure 2. Recommended Component Placement
for Single Layer Board
COMPONENT SELECTION
Inductor Selection
The LTC3400/LTC3400B can utilize small surface mount
and chip inductors due to their fast 1.2MHz switching
frequency. A minimum inductance value of 3.3µH is
necessary for 3.6V and lower voltage applications and
4.7µH for output voltages greater than 3.6V. Larger values
Figure 3. Maximum Output Current vs
Inductance Based On 90% Efficiency
V •D
IOUT(MAX) = η • IP – IN • (1 – D)
f • L • 2
where:
η = estimated efficiency
IP = peak current limit value (0.6A)
VIN = input (battery) voltage
D = steady-state duty ratio = (VOUT – VIN)/VOUT
f = switching frequency (1.2MHz typical)
L = inductance value
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LTC3400/LTC3400B
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APPLICATIO S I FOR ATIO
The inductor current ripple is typically set for 20% to 40%
of the maximum inductor current (IP). High frequency
ferrite core inductor materials reduce frequency dependent power losses compared to cheaper powdered iron
types, improving efficiency. The inductor should have low
ESR (series resistance of the windings) to reduce the I2R
power losses, and must be able to handle the peak
inductor current without saturating. Molded chokes and
some chip inductors usually do not have enough core to
support the peak inductor currents of 850mA seen on the
LTC3400/LTC3400B. To minimize radiated noise, use a
toroid, pot core or shielded bobbin inductor. See Table 1
for some suggested components and suppliers.
Table 1. Recommended Inductors
PART
L
(µH)
MAX
DCR
mΩ
HEIGHT
(mm)
2.0
2.0
1.8
1.8
3.5
3.5
0.8
0.8
Sumida
(847) 956-0666
www.sumida.com
VENDOR
extremely low ESR and are available in small footprints. A
2.2µF to 10µF output capacitor is sufficient for most
applications. Larger values up to 22µF may be used to
obtain extremely low output voltage ripple and improve
transient response. An additional phase lead capacitor
may be required with output capacitors larger than 10µF
to maintain acceptable phase margin. X5R and X7R
dielectric materials are preferred for their ability to maintain capacitance over wide voltage and temperature ranges.
Low ESR input capacitors reduce input switching noise
and reduce the peak current drawn from the battery. It
follows that ceramic capacitors are also a good choice for
input decoupling and should be located as close as possible to the device. A 4.7µF input capacitor is sufficient for
virtually any application. Larger values may be used without limitations. Table 2 shows a list of several ceramic
capacitor manufacturers. Consult the manufacturers directly for detailed information on their entire selection of
ceramic parts.
CDRH5D18-4R1
CDRH5D18-100
CDRH3D16-4R7
CDRH3D16-6R8
CR43-4R7
CR43-100
CMD4D06-4R7MC
CMD4D06-3R3MC
4.1
10
4.7
4.7
10
4.7
3.3
57
124
105
170
109
182
216
174
DS1608-472
DS1608-103
DO1608C-472
4.7
10
4.7
60
75
90
2.9
2.9
2.9
Coilcraft
(847) 639-6400
www.coilcraft.com
D52LC-4R7M
D52LC-100M
4.7
10
84
137
2.0
2.0
Toko
(408) 432-8282
www.tokoam.com
Output Diode
LQH3C4R7M24
4.7
195
2.2
Murata
www.murata.com
Table 2. Capacitor Vendor Information
Output and Input Capacitor Selection
Low ESR (equivalent series resistance) capacitors should
be used to minimize the output voltage ripple. Multilayer
ceramic capacitors are an excellent choice as they have
SUPPLIER
PHONE
WEBSITE
AVX
(803) 448-9411
www.avxcorp.com
Murata
(714) 852-2001
www.murata.com
Taiyo Yuden
(408) 573-4150
www.t-yuden.com
Use a Schottky diode such as an MBR0520L, PMEG2010EA,
1N5817 or equivalent if the converter output voltage is 4.5V
or greater. The Schottky diode carries the output current for
the time it takes for the synchronous rectifier to turn on. Do
not use ordinary rectifier diodes, since the slow recovery
times will compromise efficiency. A Schottky diode is
optional for output voltages below 4.5V, but will increase
converter efficiency by 2% to 3%.
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LTC3400/LTC3400B
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TYPICAL APPLICATIO S
Single Cell to 3.3V Synchronous Boost Converter
with Load Disconnect in Shutdown
L1
4.7µH
+
SINGLE
AA CELL
C1
4.7µF
D1
1
6
SW
VIN
VOUT
5
R3
510k
LTC3400
OFF ON
4
FB
SHDN
3
C2
4.7µF
GND
2
D1: CENTRAL SEMI CMDSH2-3
L1: COILCRAFT DS1608-472
M1
Si2305DS
R3
510k
VOUT
3.3V
R1
100mA
1.02M
1%
R2
604k
1%
Q1
2N3904
3400 TA01a
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LTC3400/LTC3400B
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TYPICAL APPLICATIO S
Single Lithium Cell to 5V, 250mA
OPTIONAL
SNUBBER
2Ω
1nF
L1
4.7µH
+
LITHIUM
CELL
D1
1
C1
4.7µF
6
SW
VIN
VOUT
5
LTC3400
4
OFF ON
FB
SHDN
3
C2
4.7µF
GND
2
D1: PHILIPS PMEG2010EA
L1: SUMIDA CMD4D06-4R7
C1, C2: TAIYO YUDEN JMK212BJ475MG
R1
1.02M
1%
C3
100pF
R2
332k
1%
3400 TA02a
3.6V to 5V Efficiency
100
EFFICIENCY (%)
90
LTC3400
CO = 4.7µF
L = 4.7µH
80
70
60
50
0.1
1
10
100
LOAD CURRENT (mA)
1000
3400 TA02b
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LTC3400/LTC3400B
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TYPICAL APPLICATIO S
Single Cell AA Cell to ±3V Synchronous Boost Converter
C3
1µF
L1
4.7µH
+
SINGLE
AA CELL
C1
4.7µF
1
6
SW
VIN
VOUT
5
LTC3400
OFF ON
4
FB
SHDN
GND
2
3
R1
1.02M
1%
R2
750k
1%
D1
D2
VOUT1
3V
C2
90mA
4.7µF
C4
10µF
3400 TA03a
VOUT2
–3V
10mA
D1, D2: ZETEX FMND7000 DUAL DIODE
L1: COILCRAFT DS1608-472
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LTC3400/LTC3400B
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PACKAGE DESCRIPTIO
S6 Package
6-Lead Plastic TSOT-23
(Reference LTC DWG # 05-08-1636)
0.62
MAX
2.90 BSC
(NOTE 4)
0.95
REF
1.22 REF
3.85 MAX 2.62 REF
1.4 MIN
2.80 BSC
1.50 – 1.75
(NOTE 4)
PIN ONE ID
RECOMMENDED SOLDER PAD LAYOUT
PER IPC CALCULATOR
0.30 – 0.45
6 PLCS (NOTE 3)
0.95 BSC
0.80 – 0.90
0.20 BSC
0.01 – 0.10
1.00 MAX
DATUM ‘A’
0.30 – 0.50 REF
0.09 – 0.20
(NOTE 3)
1.90 BSC
S6 TSOT-23 0302
NOTE:
1. DIMENSIONS ARE IN MILLIMETERS
2. DRAWING NOT TO SCALE
3. DIMENSIONS ARE INCLUSIVE OF PLATING
4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR
5. MOLD FLASH SHALL NOT EXCEED 0.254mm
6. JEDEC PACKAGE REFERENCE IS MO-193
3400fa
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.
11
LTC3400/LTC3400B
U
TYPICAL APPLICATIO
Single AA Cell to 2.5V Synchronous Boost Converter
L1
3.3µH
+
SINGLE
AA CELL
C1
4.7µF
D1
1
6
SW
VIN
VOUT
LTC3400
OFF ON
4
FB
SHDN
3
GND
D1: PHILIPS PMEG2010EA
L1: SUMIDA CMD4D06-3R3MC
VOUT
2.5V
130mA
5
2
R1
1.02M
1%
R2
1.02M
1%
C2
4.7µF
3400 TA04a
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®
3400fa
12
Linear Technology Corporation
LT/TP 0903 1K REV A • PRINTED IN USA
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