LT3482
90V Boost DC/DC
Converter with APD
Current Monitor
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FEATURES
DESCRIPTIO
■
The LT®3482 is a fixed frequency current mode step-up
DC/DC converter with voltage doubler designed to bias
avalanche photodiodes (APDs) in optical receivers. It can
provide up to 90V output. The LT3482 features high side
APD current monitoring with better than 10% relative accuracy over the entire temperature range. The integrated
power switch, Schottky diodes and APD current monitor
allow a small converter footprint and low solution cost.
Constant switching frequency results in predictable output
noise that is easy to filter. The inductor-based topology
ensures an input free from switching noise. An integrated
high side current monitor produces a current proportional
to APD current with better than 10% relative accuracy
over four decades of dynamic range in the input range of
250nA to 2.5mA. This current can be used as a reference
to provide a digitally programmed output voltage via the
CTRL pin. The LT3482 is available in the tiny footprint
(3mm × 3mm) 16-lead QFN package.
■
■
■
■
■
■
■
■
■
■
■
High Output Voltage: Up to 90V
Integrated Schottky Diodes
48V, 280mA Internal Switch
High Side APD Current Monitor
Adjustable Switching Frequency: 650kHz or 1.1MHz
Wide VIN Range: 2.5V to 16V
Surface Mount Components
Low Shutdown Current: <1µA
Soft-Start
Internal Compensation
CTRL Pin Allows Output Adjustment with No Polarity
Inversion
3mm × 3mm 16-Lead QFN Package
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APPLICATIO S
■
■
■
■
APD Bias
PIN Diode Bias
Optical Receivers and Modules
Fiber Optic Network Equipment
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
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TYPICAL APPLICATIO
0.1µF
10µH
VIN
5V
Output Voltage Ripple
SW
1µF
PUMP
MONIN
VIN
fSET
OFF ON
LT3482
VOUT2
SHDN
0.47µF
CTRL
VOUT1
GND
MON
10nF
0.1µF
1M
0.47µF
VAPD
RIPPLE
100mV/DIV
FB
APD
10k
85V
AT 2.5mA
14k
0.1µF
3482 TA01a
500ns/DIV
3482 TA01b
3482fa
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LT3482
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ABSOLUTE
RATI GS
PIN CONFIGURATION
(Note 1)
CTRL
FB
fSET
MON
TOP VIEW
16 15 14 13
NC 1
12 SHDN
APD 2
11 VIN
17
MONIN 3
10 GND
VOUT2 4
6
7
8
VOUT1
SW
SW
9
5
PUMP
Input Voltage (VIN) ....................................................16V
VOUT1, SW Voltage ....................................................48V
VOUT2, PUMP, MONIN, APD Voltage..........................90V
FB Voltage ...................................................................5V
SHDN, fSET, CTRL Voltage .........................................16V
MON Voltage .............................................................12V
Operating Temperature Range
(Note 2).................................................... –40°C to 85°C
Maximum Junction Temperature .......................... 125°C
Storage Temperature Range................... –65°C to 125°C
GND
UD PACKAGE
16-LEAD (3mm × 3mm) PLASTIC QFN
TJMAX = 125°C, θJA = 68°C/W, θJC = 4.2°C/W
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT3482EUD#PBF
LT3482IUD#PBF
LT3482EUD#TRPBF
LT3482IUD#TRPBF
LCFG
LCFG
16-Lead (3mm × 3mm) Plastic QFN
16-Lead (3mm × 3mm) Plastic QFN
0°C to 85°C
–40°C to 125°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free parts, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VIN = 3V, V⎯S⎯H⎯D⎯N = 3V unless otherwise noted.
PARAMETER
CONDITIONS
MIN
Minimum Operating Voltage
TYP
2.5
CTRL = 1.5V
●
1.215
1.200
Feedback Line Regulation
●
FB Pin Bias Current
Supply Current
FB = 1.3V, Not Switching
V⎯S⎯H⎯D⎯N = 0
Switching Frequency
fSET = 0V
fSET = 2V
Maximum Duty Cycle
fSET = 0V
Switch Current Limit
ISW = 150mA
Switch Leakage Current
SW = 5V
Schottky Forward Voltage
ISCHOTTKY = 150mA
Schottky Reverse Leakage
VOUT1 – SW = 50V
16
V
1.235
1.255
1.260
V
V
0.025
0.07
%/V
30
100
nA
3.3
0.1
4.0
0.5
mA
µA
650
1.1
750
1.3
kHz
MHz
360
420
mA
130
220
mV
2
µA
95
280
Switch VCESAT
SHDN Voltage High
580
1.0
%
880
mV
5
1.5
UNITS
V
Maximum Operating Voltage
Feedback Voltage
MAX
µA
V
3482fa
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LT3482
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VIN = 3V, V⎯S⎯H⎯D⎯N = 3V unless otherwise noted.
PARAMETER
CONDITIONS
MIN
TYP
SHDN Voltage Low
SHDN Pin Bias Current
35
fSET Voltage High
MAX
0.4
V
50
µA
1.5
V
fSET Voltage Low
fSET Bias Current
fSET = 2V
CTRL to FB Offset
CTRL = 0.5V
APD Current Monitor Gain
IAPD = 250nA, 10V ≤ MONIN ≤ 90V
IAPD = 2.5mA, 20V ≤ MONIN ≤ 90V
Monitor Output Voltage Clamp
0.4
V
22
40
µA
mV
mV
●
–5
–10
2
2
10
15
●
●
0.180
0.185
0.20
0.20
0.215
0.215
11.5
APD Monitor Voltage Drop
MONIN – APD at IAPD = 1mA, MONIN = 90V
MONIN Pin Current Limit
APD = 0V, MONIN = 40V
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.
UNITS
V
5
15
V
mA
Note 2: The LT3482E is guaranteed to meet specified performance from
0°C to 85°C. Specifications over the –40°C to 85°C operating temperature
range are assured by design, characterization and correlation with statistical process controls. The LT3482I is guaranteed to meet performance
specifications over the –40°C to 125°C operating temperature range.
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LT3482
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TYPICAL PERFOR A CE CHARACTERISTICS (TA = 25°C unless otherwise specified)
Oscillator Frequency vs
Temperature
SWITCH CURRENT LIMIT (mA)
1100
FREQUENCY (kHz)
fSET = 2V
1000
900
800
fSET = 0V
600
400
360
350
340
SWITCH CURRENT LIMIT (mA)
1200
700
300
250
200
150
100
50
25
75
0
TEMPERATURE (°C)
100
0
125
20
0
40
60
DUTY CYCLE (%)
3482 G01
1.0E-02
80
70
80
90
–2
1.0E-06
–8
1.0E-06
1.0E-04
IAPD (A)
3482 G04
50
25
75
0
TEMPERATURE (°C)
100
125
3482 G06
Switch Saturation Voltage (VCESAT)
FB Pin Voltage vs Temperature
1.25
300
VCESAT (mV)
4
3
FB PIN VOLTAGE (V)
250
5
MONIN – APD (V)
–10
–50 –25
1.0E-02
IAPD = 2.5mA
IAPD = 10µA
IAPD = 250nA
3482 G05
6
200
150
100
2
1.24
VIN = 16V
VIN = 3V
1.23
50
1
0
1.00E-07
–4
–6
1.0E-09
1.0E-08
7
125
0
1.0E-05
Current Monitor Voltage Drop
vs Reference Current
100
MONIN = 90V
ERROR (%)
IMON (µA)
IMON (A)
40 50 60
MONIN (V)
50
75
25
TEMPERATURE (°C)
2
MONIN = 90V
1.0E-08
30
0
APD Current Monitor Accuracy
vs Temperature
1.0E-07
20
240
3482 G03
1.0E-04
10
260
200
–50 –25
100
1.0E-03
21
18
280
APD Current Monitor Accuracy
IAPD = 100µA
19
300
3482 G02
Current Monitor Output vs MONIN
20
320
220
50
500
–50 –25
22
Switch Current Limit vs
Temperature
Switch Current Limit
vs Duty Cycle
0
1.00E-05
1.00E-03
REFERENCE CURRENT (A)
!"& /%
0
50
100 150 200 250 300
SWITCH CURRENT (mA)
350
3482 G08
1.22
–50 –25
50
25
75
0
TEMPERATURE (°C)
100
125
3482 G09
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LT3482
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PI FU CTIO S
APD (Pin 2): Connect APD cathode to this pin.
MONIN (Pin 3): Current Monitor Power Supply Pin. An
external lowpass filter can be included here to further
reduce supply voltage ripple.
VOUT2 (Pin 4): Voltage Doubler Output Pin. Put a 50V
rated capacitor between this pin and VOUT1. Tie a resistor
divider to the FB pin and GND.
VOUT1 (Pin 5): Boost Output Pin. Put a capacitor between
this pin and the GND plane. Minimize the length of the
trace to the capacitor.
PUMP (Pin 6): Charge Pump Pin. Put a 50V rating bypass
capacitor between SW and PUMP to form a complete voltage doubler with the internal integrated Schottky diodes.
Minimize trace length to the capacitor.
SHDN (Pin 12): Shutdown Pin. Tie to 1.5V or higher to
enable device; 0.4V or less to disable device. This pin also
functions as soft-start between 1.5V and 2V.
CTRL (Pin 13): Internal Reference Override Pin. This allows
the FB voltage to be externally set between 0V and 1.2V.
Tie this pin higher than 1.5V to use the internal reference
of 1.235V.
FB (Pin 14): Feedback Pin. Connect the output resistor
divider tap here.
fSET (Pin 15): Oscillator Frequency Selection Pin. Tie this
pin to above 1.5V or higher to select the higher switching
frequency of 1.1MHz. For lower switching frequency, tie
to GND.
SW (Pins 7, 8): Switch Pin. Minimize the trace length on
this pin to reduce EMI.
MON (Pin 16): Current Monitor Output Pin. It sources a
current equal to 20% of the APD current and converts to
a reference voltage through an external resistor.
GND (Pins 9, 10): Ground. Pins connected internally. For
best performance, connect both pins to board ground.
Exposed Pad (Pin 17): GND. This pin must be soldered
to the PCB.
VIN (Pin 11): Input Supply Pin. This pin must be locally
bypassed.
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LT3482
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FU CTIO AL DIAGRA
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CFLY
L1
VIN
11
7
VIN
SW
8
6
SW
9 GND
D1
PUMP
D3
D2
VOUT2
VOUT1
10 GND
1.235V
REFERENCE
+
+
–
MONIN
–
A1
RC
EAMP
+
CC
4
Q1
R S Q
A2
PWM
COMPARATOR
+
CS
13
CTRL
14
FB
R2
FB
APD
CURRENT
MIRROR
APD
2
C3
CURRENT
SENSE
AMPLIFIER
650kHz/1.1MHz
OSCILLATOR
12 SHDN
C1
CPL
3
–
RAMP
GENERATOR
RS
R1
DRIVER
Σ
VIN
C2
5
NC 1
15
fSET
16
MON
3482 BD
CONTROL
BLOCK
R3
C4
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OPERATIO
The LT3842 boost converter uses a constant frequency
current mode control scheme to provide excellent line
and load regulation. Operation can be best understood by
referring to the Functional Diagram. At the start of each
oscillator cycle, the SR latch is set, which turns on the
power switch, Q1. A voltage proportional to the switch
current is added to a stabilizing ramp and the resulting sum
is fed into the positive terminal of the PWM comparator,
A2. When this voltage exceeds the level at the negative
input of A2, the SR latch is reset turning off the power
switch. The level at the negative input of A2 is set by the
error amplifier A1, and is simply an amplified version of the
difference between the feedback voltage and the reference
voltage of 1.235V, or externally provided CTRL voltage.
In this manner, the error amplifier sets the correct peak
current level to keep the output in regulation. If the error
amplifier’s output increases, more current is delivered to
the output; if it decreases, less current is delivered.
The LT3482 has an integrated high side APD current monitor with a 5:1 ratio. The MONIN pin can accept a supply
voltage up to 90V, which is suitable for APD photodiode
applications. The MON pin has an open-circuit protection
feature and is internally clamped to 11.5V.
If an APD is tied to the APD pin, the current will be mirrored to the MON pin and converted to a voltage signal
by the resistor R3. This voltage signal can be used to
drive an external control block to adjust the APD voltage
by adjusting the feedback threshold of EAMP A1 through
the CTRL input.
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LT3482
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APPLICATIO S I FOR ATIO
Table 1. Inrush Peak Current
Switching Frequency
The LT3482 can operate at either 650kHz nominal or
1.1MHz nominal; the voltage at the fSET pin selects which
frequency is used. At 1.1MHz, a physically smaller inductor and capacitor can be used in a given application, but
higher frequencies will slightly decrease efficiency and
maximum duty cycle. Generally if efficiency and maximum
duty cycle are crucial, the lower switching frequency should
be selected by connecting fSET to GND. If application size
and cost are more important, connect fSET to VIN to select
the higher switching frequency.
VIN (V)
L (µH)
C (µF)
IP (A)
5
10
1
0.87
5
22
1
0.68
Setting Output Voltage
The LT3482 is equipped with both an internal 1.235V reference and an auxiliary reference input (the CTRL pin). This
allows users to select between using the built-in reference
and supplying an external reference voltage. The voltage
at the CTRL pin can be adjusted while the chip is operating
to alter the output voltage of LT3482 for purposes such as
APD’s bias voltage adjustment. To use the internal 1.235V
reference, the CTRL pin should be held higher than 1.5V,
which can be done by tying it to VIN. When the CTRL
pin is between 0V and 1.2V, the LT3482 will regulate the
output such that the FB pin voltage is equal to the CTRL
pin voltage.
Inrush Current
The LT3482 has built-in Schottky diodes for the boost
and charge pump. When supply voltage is applied to the
VIN pin, the voltage difference between VIN and VOUT1
generates inrush current flowing from input through the
inductor and the Schottky diode (D1 in the Functional
Diagram) to charge the output capacitor. The selection of
inductor and capacitor value should ensure the peak of
the inrush current to be below 1A. In addition, the LT3482
turn-on should be delayed until the inrush current is less
than the maximum current limit. The peak inrush current
can be estimated as follows:
To set the output voltage, select the values of R1 and R2
(see Figure 1) according to the following equation:
⎛V
⎞
R1= R2 ⎜ OUT2 – 1⎟
⎝ VREF
⎠
where VREF = 1.235V if the internal reference is used or
VREF = CTRL if CTRL is between 0V and 1.2V. R2 can be
selected to load the output to maintain a constant switching
frequency when the APD load is very low. Preventing entry
into pulse skipping mode is an important consideration
for post filtering the regulator output.
⎛
⎞
⎜
V – 0.6
π ⎟
• exp ⎜ –
IP = IN
⎟
L
L ⎟
⎜
–1
– 1⎟
⎜⎝ 2
C
C ⎠
where L is the inductance and C is the output capacitance.
Table 1 gives inrush peak currents for some component
selections.
VOUT2
4
R1
LT3482
13
CTRL
FB
14
R2
3482 F01
Figure 1. Output Voltage Feedback Connection
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LT3482
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APPLICATIO S I FOR ATIO
Inductor Selection
The inductors used with the LT3482 should have a saturation current rating of 0.3A or greater. If the device is used in
an application where the input supply will be hot-plugged,
the saturation current rating should be equal to or greater
than the peak inrush current. For best loop stability, the
inductor value selected should provide a ripple current of
60mA or more. For a given VIN and VOUT1, the inductor
value to use in continuous conduction mode (CCM) is
estimated by the formula:
D • VIN
L=
ƒ • 60mA
where:
D=
VOUT1 + 1– VIN
VOUT1 + 1
and f is the switching frequency.
To achieve low output voltage ripple, a small value inductor should be selected to force the LT3482 work in
discontinuous conduction mode (DCM). The inequality
is true when the LT3482 is operating in discontinuous
condition mode.
L<
D • VIN
ƒ • ILIMIT
where ILIMIT is the switch current limit. Operating in DCM
reduces the maximum load current and the conversion
efficiency.
Capacitor Selection
Low ESR capacitors should be used at the output to
minimize the output voltage ripple. Use only X5R and
X7R types because they retain their capacitance over
wider voltage and temperature ranges than other types.
High output voltages typically require less capacitance for
loop stability. For applications with out voltage less than
45V, intermediate output pin VOUT1 can directly serve as
the output pin. Typically use a 2µF capacitor for output
voltage less than 25V and 1µF capacitor for output voltage
between 25V and 45V. When output voltage goes beyond
45V, a charge pump must be formed with cascaded 0.47µF
capacitors C1 and C2 at the output nodes. A typical 0.1µF
capacitor is used as the flying capacitor CFLY to form the
charge pump. Always use a capacitor with sufficient voltage rating.
Either ceramic or solid tantalum capacitors may be used
for the input decoupling capacitor, which should be placed
as close as possible to the LT3482. A 1µF capacitor is
sufficient for most applications.
Phase Lead Capacitor
A small value capacitor (i.e., 10pF to 22pF) can be added
in parallel with the resistor between the output and the FB
pin to reduce output perturbation due to a load step and
to improve transient response. This phase lead capacitor
introduces a pole-zero pair to the feedback that boosts
phase margin near the crossover frequency.
The APD is very sensitive to a noisy bias supply. To
lowpass filter noise from the internal reference and error
amplifier, a 0.1µF phase lead capacitor can be used. The
corner frequency of the noise filter is R1 • CPL.
APD Current Monitor
The power supply switching noise associated with a switching power supply can interfere with the photodiode DC
measurement. To suppress this noise, a 0.1µF capacitor
is recommended at APD pin. An additional output lowpass
filter, a 10k resistor and a 10nF capacitor in parallel at
MON pin, can further reduce the power supply noise and
other wide band noise, which might limit the measurement
accuracy of low level signals. For applications requiring
fast current monitor response time, a RC lowpass filter at
MONIN pin is used to replace the 0.1µF capacitor at APD
pin, as illustrated in Figure 2.
RMON
MONIN
CMON
LT3482
VOUT2
C2
VOUT1
C1
APD
3482 F02
Figure 2
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APPLICATIO S I FOR ATIO
In some applications, a long cable or wire is used to connect
the LT3482 to APD. When APD is shorted to GND, APD pin
voltage might ring below ground and damage the internal
circuitry. To prevent damage during short-circuit event, a
20Ω resistor must be added in series with the APD.
Layout Hints
The high speed operation of the LT3842 demands careful attention to board layout. You will not get advertised
performance with careless layout. Figure 3 shows the
recommended component placement.
MON fSET
CTRL
R2
VIN
R1
16
15
14
13
CPL
1
APD
12
2
11
17
CMON
(OPT)
RMON
(OPT)
3
10
4
9
5
C2
6
7
CIN
GND
L1
8
CFLY
C1
3482 F03
Figure 3. Suggested Layout
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LT3482
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TYPICAL APPLICATIO S
5V to 85V APD Bias Power Supply
60
C2
0.1µF
L1
10µH
VIN
5V
Efficiency
50
SW
VIN
fSET
OFF ON
PUMP
MONIN
EFFICIENCY (%)
C1
1µF
LT3482
SHDN
VOUT2
CTRL
VOUT1
GND
C4
0.47µF
C5
0.47µF
FB
MON
R3
10k
30
20
10
R2
14k
85V
AT 2.5mA
APD
C7
10nF
R1
1M
C6
0.1µF
40
0
0
C3
0.1µF
0.5
1
2
1.5
2.5
IMONIN (mA)
3
3482 TA02a
3.5
3482 TA02b
C1: MURATA X7R GRM21BR71C105KA01B
C2: AVX 06035C104KAT2A
C3, C6: AVX 08051C104KAT2A
C4, C5: MURATA X7R GRM31MR71H474KA01B
C7: MURATA GRM2167U1H103JA01B
L1: COILCRAFT ME3220-103KL OR EQUIVALENT
3.3V to 70V APD Bias Power Supply with Fast Current Monitor Response
C2
0.1µF
L1
6.8µH
VIN
3.3V
60
SW
VIN
fSET
PUMP
MONIN
R1
100Ω
LT3482
SHDN
VOUT2
CTRL
VOUT1
GND
C4
0.47µF
C5
0.47µF
FB
MON
R4
10k
C6
0.1µF
R2
1M
C3
0.1µF
40
30
20
10
R3
16.5k
APD
EFFICIENCY (%)
50
C1
1µF
OFF ON
Efficiency
0
0
70V
AT 2mA
0.5
1
1.5
IMONIN (mA)
2
2.5
3482 TA03a
3482 TA03b
C1: MURATA X7R GRM21BR71C105KA01B
C2: AVX 06035C104KAT2A
C3, C6: AVX 08051C104KAT2A
C4, C5: MURATA X7R GRM31MR71H474KA01B
L1: COILCRAFT ME3220-682ML OR EQUIVALENT
APD Input Load for Current Monitor
Step Response Measurement
Current Monitor Step Response
2 APD
5V
VMON
2V/DIV
REF GND
0V
2mA
VNODE A
20V/DIV
10k
NODE A
2k
0mA
REF GND
500ns/DIV
3482 TA03c
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LT3482
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PACKAGE DESCRIPTIO
UD Package
16-Lead Plastic QFN (3mm × 3mm)
(Reference LTC DWG # 05-08-1691)
0.70 ±0.05
3.50 ± 0.05
1.45 ± 0.05
2.10 ± 0.05 (4 SIDES)
PACKAGE OUTLINE
0.25 ±0.05
0.50 BSC
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
3.00 ± 0.10
(4 SIDES)
BOTTOM VIEW—EXPOSED PAD
PIN 1 NOTCH R = 0.20 TYP
OR 0.25 × 45° CHAMFER
R = 0.115
TYP
0.75 ± 0.05
15
16
PIN 1
TOP MARK
(NOTE 6)
0.40 ± 0.10
1
1.45 ± 0.10
(4-SIDES)
2
(UD16) QFN 0904
0.200 REF
0.00 – 0.05
NOTE:
1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE MO-220 VARIATION (WEED-2)
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION
ON THE TOP AND BOTTOM OF PACKAGE
0.25 ± 0.05
0.50 BSC
3482fa
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
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LT3482
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TYPICAL APPLICATIO
3.3V to 40V APD Bias Power Supply
Efficiency
L1
5.6mH
VIN
3.3V
70
60
SW
VIN
fSET
OFF ON
PUMP
MONIN
50
R3
100W
LT3482
VOUT2
SHDN
CTRL
VOUT1
GND
C2
1mF
FB
MON
R4
10k
C3
0.1mF
R1
1M
C4
0.1mF
40
30
20
10
R2
28k
APD
EFFICIENCY (%)
C1
1mF
0
40V
AT 3mA
0
3482 TA04a
0.5
1
1.5
2
2.5
3
3.5
4
IMONIN (mA)
3482 TA04b
C1: MURATA X7R GRM21BR71C105KA01B
C2: MURATA X7R GRM31MR71H105KA88B
C3, C4: AVX 06035C104KAT2A
L1: COILCRAFT ME3220-562ML OR EQUIVALENT
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PART NUMBER
DESCRIPTION
COMMENTS
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Package
ThinSOT is a trademark on Linear Technology Corporation.
3482fa
12 Linear Technology Corporation
LT 0207 REV A • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
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© LINEAR TECHNOLOGY CORPORATION 2006