LINER LT3465AES6

LT3465/LT3465A
1.2MHz/2.4MHz White LED
Step-Up Converters with
Built-In Schottky in ThinSOT
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DESCRIPTIO
FEATURES
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Inherently Matched LED Current
Drives Up to Six LEDs from a 3.6V Supply
No External Schottky Diode Required
1.2MHz Switching Frequency (LT3465)
2.4MHz Switching Frequency Above AM Broadcast
Band (LT3465A)
Automatic Soft-Start (LT3465)
Open LED Protection
High Efficiency: 81% (LT3465) 79% (LT3465A)
Typical
Requires Only 0.22µF Output Capacitor
Low Profile (1mm) SOT-23 Packaging
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APPLICATIO S
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Cellular Phones
PDAs, Handheld Computers
Digital Cameras
MP3 Players
GPS Receivers
The LT3465 switches at 1.2MHz, allowing the use of tiny
external components. The faster LT3465A switches at
2.4MHz. Constant frequency switching results in low input
noise and a small output capacitor. Just 0.22µF is required
for 3-, 4- or 5-LED applications.
The LT3465 and LT3465A are available in low profile
(1mm) 6-lead SOT-23 (ThinSOTTM) packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
ThinSOT is a trademark of Linear Technology Corporation.
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The LT®3465/LT3465A are step-up DC/DC converters
designed to drive up to six LEDs in series from a Li-Ion cell.
Series connection of the LEDs provides identical LED
currents and eliminates the need for ballast resistors.
These devices integrate the Schottky diode required externally on competing devices. Additional features include
output voltage limiting when LEDs are disconnected, onepin shutdown and dimming control. The LT3465 has
internal soft-start.
TYPICAL APPLICATIO
Conversion Efficiency
L1
22µH
82
VIN = 3.6V
80 4 LEDs
3V TO 5V
78
VOUT
VIN
SHUTDOWN
AND DIMMING
CONTROL
C1
1µF
LT3465/
LT3465A
CTRL
FB
GND
C1, C2: X5R OR X7R DIELECTRIC
L1: MURATA LQH32CN220
C2
0.22µF
10Ω
3465A F01a
EFFICIENCY (%)
SW
76
74
72
70
68
66
64
60
Figure 1. Li-Ion Powered Driver for Four White LEDs
LT3465
LT3465A
62
0
5
10
15
20
LED CURRENT (mA)
3465A F01b
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LT3465/LT3465A
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PACKAGE/ORDER I FOR ATIO
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ABSOLUTE
RATI GS
(Note 1)
Input Voltage (VIN) ................................................. 16V
SW Voltage ............................................................. 36V
FB Voltage ................................................................ 2V
CTRL Voltage .......................................................... 10V
Operating Temperature Range (Note 2) .. – 40°C to 85°C
Maximum Junction Temperature ......................... 125°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
ORDER PART
NUMBER
TOP VIEW
VOUT 1
6 SW
GND 2
5 VIN
LT3465ES6
LT3465AES6
4 CTRL
FB 3
S6 PACKAGE
6-LEAD PLASTIC TSOT-23
TJMAX = 125°C, θJA = 256°C/W IN FREE AIR
θJA = 120°C ON BOARD OVER GROUND PLANE
S6 PART MARKING
LTH2
LTAFT
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 = 3V, VCTRL = 3V, unless otherwise noted.
PARAMETER
CONDITIONS
MIN
Minimum Operating Voltage
LT3465
TYP
2.7
LT3465A
TYP
16
V
200
212
188
200
212
mV
10
35
100
10
35
100
nA
1.9
2.0
2.6
3.2
3.3
5.0
1.9
2.0
2.6
3.2
3.3
5.0
mA
µA
0.8
1.2
1.6
1.8
2.4
2.8
MHz
●
90
93
90
93
%
●
225
340
225
340
mA
300
mV
Not Switching
CTRL = 0V
Switching Frequency
Switch Current Limit
Switch VCESAT
ISW = 250mA
300
Switch Leakage Current
VSW = 5V
0.01
VCTRL for Full LED Current
5
1.8
0.01
Soft-Start Time
48
40
60
µA
50
mV
72
60
90
µA
µA
µA
V
50
TA = 85°C
TA = –40°C
5
1.8
VCTRL to Shut Down Chip
CTRL Pin Bias Current
60
50
75
72
60
90
48
40
60
60
50
75
µs
600
Schottky Forward Drop
ID = 150mA
Schottky Leakage Current
VR = 30V
UNITS
V
16
Maximum Duty Cycle
MAX
188
0°C ≤ TA ≤ 85°C
FB Pin Bias Current
Supply Current
MIN
2.7
Maximum Operating Voltage
Feedback Voltage
MAX
0.7
0.7
4
V
4
µA
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The LT3465E/LT3465AE are guaranteed to meet performance
specifications from 0°C to 70°C. Specifications over the –40°C to 85°C
operating temperature range are assured by design, characterization and
correlation with statistical process controls.
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LT3465/LT3465A
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TYPICAL PERFOR A CE CHARACTERISTICS
Switch Saturation Voltage (VCESAT)
300
400
350
300
250
200
150
100
50
0
100 150 200 250
SWITCH CURRENT (mA)
300
250
24
21
200
150
18
15
12
100
9
6
50
3
350
1000
400
600
800
200
SCHOTTKY FORWARD DROP (mV)
0
0
1200
4
2
6
10
8
VIN (V)
12
3465A G02
3465A G01
VFB vs VCTRL
250
TA = 25°C
27
0
50
0
30
TA = 25°C
IQ (µA)
TA = 25°C
SCHOTTKY FORWARD CURRENT (mA)
SWITCH SATURATION VOLTAGE (mV)
450
Shutdown Quiescent Current
(CTRL = 0V)
Schottky Forward Voltage Drop
TA = 25°C
16
3465A G03
Open-Circuit Output Clamp Voltage
Input Current in Output Open Circuit
5
35
14
TA = 25°C
TA = 25°C
150
100
50
4
INPUT CURRENT (mA)
OUTPUT CLAMP VOLTAGE (V)
FEEDBACK VOLTAGE (mV)
30
200
25
20
15
10
3
2
1
5
0
0
0
0
1
0.5
1.5
CONTROL VOLTAGE (V)
2
2
4
10
8
12
6
INPUT VOLTAGE (V)
3465A G04
14
2
16
2.5
4
3
3.5
INPUT VOLTAGE (V)
5
3465A G06
3465A G05
Switching Waveforms (LT3465)
4.5
Switching Frequency
Switching Waveforms (LT3465A)
VSW
10V/DIV
VSW
10V/DIV
IL
100mA/DIV
IL
50mA/DIV
VOUT
100mV/DIV
VOUT
50mV/DIV
VIN = 3.6V
4 LEDs
20mA, 22µH
200ns/DIV
3465A G07a
VIN = 3.6V
4 LEDs
20mA, 22µH
100ns/DIV
3465A G07b
SWITCHING FREQUENCY (MHz)
3.0
2.5
LT3465A
2.0
1.5
LT3465
1.0
0.5
0
–50
50
0
TEMPERATURE (°C)
100
4365A G08
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LT3465/LT3465A
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TYPICAL PERFOR A CE CHARACTERISTICS
Quiescent Current (CTRL = 3V)
Feedback Voltage
Switching Current Limit
3.0
210
400
350
204
CURRENT LIMIT (mA)
2.5
206
2.0
202
IQ (mA)
FEEDBACK VOLTAGE (mV)
208
200
1.5
198
1.0
196
194
–50°C
25°C
100°C
0.5
192
190
–50 –30 –10 10 30 50
TEMPERATURE (°C)
0
90
5
10
VIN (V)
15
EFFICIENCY (%)
70
65
100
SCHOTTKY LEAKAGE CURRENT (µA)
20mA
10mA
50
0
TEMPERATURE (°C)
–50°C
25°C
100°C
0
20
40
60
DUTY CYCLE (%)
80
100
3465A G11
Schottky Leakage Current
15mA
60
–50
100
8
80
75
150
3465A G10
VIN = 3.6V, 4 LEDs
LT3465
LT3465A
200
0
20
3465A G09
85
250
50
0
70
300
7
VR = 25
6
VR = 16
5
VR = 10
4
3
2
1
0
–50
0
50
100
TEMPERATURE (°C)
3465A G12
3465A G13
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PI FU CTIO S
VOUT (Pin 1): Output Pin. Connect to output capacitor and
LEDs. Minimize trace between this pin and output capacitor to reduce EMI.
GND (Pin 2): Ground Pin. Connect directly to local ground
plane.
FB (Pin 3): Feedback Pin. Reference voltage is 200mV.
Connect LEDs and a resistor at this pin. LED current is
determined by the resistance and CTRL pin voltage:
CTRL (Pin 4): Dimming Control and Shutdown Pin. Ground
this pin to shut down the device. When VCTRL is greater
than about 1.8V, full-scale LED current is generated. When
VCTRL is less than 1V, LED current is reduced.
VIN (Pin 5): Input Supply Pin. Must be locally bypassed
with a 1µF X5R or X7R type ceramic capacitor.
SW (Pin 6): Switch Pin. Connect inductor here.
200mV
When VCTRL > 1.8 V
RFB
V
ILED ≈ CTRL When VCTRL < 1V
5 • RFB
ILED ≈
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LT3465/LT3465A
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BLOCK DIAGRA
VIN
FB
5
3
VREF
1.25V
200mV
–
+
+
6 SW
–
A1
1
DRIVER
RC
+
A2
R
Q1
Q
S
OVERVOLTAGE
PROTECT
CC
+
Σ
0.2Ω
10k
CTRL
VOUT
COMPARATOR
–
RAMP
GENERATOR
40k
4
2 GND
1.2MHz*
OSCILLATOR
3465A F02
*2.4MHz FOR LT3465A
Figure 2. LT3465 Block Diagram
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APPLICATIO S I FOR ATIO
Operation
The LT3465 uses a constant frequency, current mode
control scheme to provide excellent line and load regulation. Operation can be best understood by referring to the
block diagram in Figure 2. 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
200mV. 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 CTRL pin voltage is used to adjust the
reference voltage. The block diagram for the LT3465A (not
shown) is identical except that the oscillator frequency is
2.4MHz.
Minimum Output Current
The LT3465 can drive a 3-LED string at 1.5mA LED
current without pulse skipping. As current is further
reduced, the device will begin skipping pulses. This will
result in some low frequency ripple, although the LED
current remains regulated on an average basis down to
zero. The photo in Figure 3a details circuit operation
driving three white LEDs at a 1.5mA load. Peak inductor
current is less than 40mA and the regulator operates in
discontinuous mode, meaning the inductor current
VSW
5V/DIV
IL
20mA/DIV
VOUT
10mV/DIV
VIN = 4.2V
ILED = 1.5mA
3 LEDs
0.2µs/DIV
3465A F03a
Figure 3a. Switching Waveforms (LT3465)
VSW
5V/DIV
IL
20mA/DIV
VOUT
10mV/DIV
VIN = 4.2V
ILED = 0.2mA
3 LEDs
0.1µs/DIV
3465A F03b
Figure 3b. Switching Waveforms (LT3465A)
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LT3465/LT3465A
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APPLICATIO S I FOR ATIO
85
VIN = 3.6V
4 LEDs
80
75
EFFICIENCY (%)
reaches zero during the discharge phase. After the inductor current reaches zero, the SW pin exhibits ringing due
to the LC tank circuit formed by the inductor in combination with switch and diode capacitance. This ringing is
not harmful; far less spectral energy is contained in the
ringing than in the switch transitions. The ringing can be
damped by application of a 300Ω resistor across the
inductor, although this will degrade efficiency. Because
of the higher switching frequency, the LT3465A can drive
a 3-LED string at 0.2mA LED current without pulse
skipping. The photo in Figure 3b detials circuit operation
driving three white LEDs at a 0.2mA load. Peak inductor
current is less than 30mA.
70
65
60
MURATA LQH32CN220
TAIYO YUDEN LB2012B220M
TAIYO YUDEN CB2012B220
55
50
0
5
10
20
15
LED CURRENT (mA)
3465A F04b
Figure 4a. Efficiency Comparison of Different Inductors (LT3465)
Inductor Selection
80
A 22µH inductor is recommended for most LT3465 applications. Although small size and high efficiency are major
concerns, the inductor should have low core losses at
1.2MHz and low DCR (copper wire resistance). Some
inductors in this category with small size are listed in
Table␣ 1. The efficiency comparison of different inductors
is shown in Figure 4a. A 22µH or 10µH inductor is
recommended for most LT3465A applications. The inductor should have low core losses at 2.4MHz and low DCR.
The efficiency comparison of different inductors is shown
in figure 4b.
VIN = 3.6V
4 LEDs
EFFICIENCY (%)
75
70
65
MURATA LQH32CN220
MURATA LQH32CN100
MURATA LQH2MCN220
TOKO D312-220
TOKO D312-100
TAIYO YUDEN LB2012B220
60
55
50
0
5
10
20
15
LED CURRENT (mA)
3465A F04b
Table 1. Recommended Inductors
PART
NUMBER
Figure 4b. Efficiency Comparison of Different Inductors (LT3465A)
DCR (Ω)
CURRENT RATING
(mA)
LQH32CN220
LQH2MCN220
0.71
2.4
250
185
Murata
814-237-1431
www.murata.com
ELJPC220KF
4.0
160
Panasonic
714-373-7334
www.panasonic.com
CDRH3D16-220
0.53
350
Sumida
847-956-0666
www.sumida.com
LB2012B220M
1.7
75
Taiyo Yuden
408-573-4150
www.t-yuden.com
Table 2. Recommended Ceramic Capacitor Manufacturers
MANUFACTURER
PHONE
URL
Taiyo Yuden
408-573-4150
www.t-yuden.com
Taiyo Yuden
408-573-4150
www.t-yuden.com
Murata
814-237-1431
www.murata.com
Kemet
408-986-0424
www.kemet.com
LEM2520-220
5.5
125
MANUFACTURER
Capacitor Selection
The small size of ceramic capacitors makes them ideal for
LT3465 and LT3465A applications. X5R and X7R types are
recommended because they retain their capacitance over
wider voltage and temperature ranges than other types
such as Y5V or Z5U. A 1µF input capacitor and a 0.22µF
output capacitor are sufficient for most LT3465 and
LT3465A applications.
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LT3465/LT3465A
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APPLICATIO S I FOR ATIO
Soft-Start (LT3465)
The LT3465 has an internal soft-start circuit to limit the
input current during circuit start-up. The circuit start-up
waveforms are shown in Figure 5.
IIN 50mA/DIV
Table 3 gives inrush peak currents for some component
selections.
Table 3. Inrush Peak Current
VIN (V)
r (Ω)
L (µH)
C (µF)
IP (A)
5
0.5
22
0.22
0.38
5
0.5
22
1
0.70
3.6
0.5
22
0.22
0.26
5
0.5
33
1
0.60
VOUT 5V/DIV
VFB 100mV/DIV
LED Current and Dimming Control
CTRL 5V/DIV
VIN = 3.6V
4 LEDs, 20mA
L = 22µH
C = 0.22µF
200µs/DIV
3465 F05
ILED = VFB/RFB
Figure 5. Start-Up Waveforms
Inrush Current
The LT3465 and LT3465A have a built-in Schottky diode.
When supply voltage is applied to the VIN pin, the voltage
difference between VIN and VOUT generates inrush current
flowing from input through the inductor and the Schottky
diode to charge the output capacitor to VIN. The maximum
current the Schottky diode in the LT3465 and LT3465A
can sustain is 1A. The selection of inductor and capacitor
value should ensure the peak of the inrush current to be
below 1A. The peak inrush current can be calculated as
follows:
IP =
α=
 α

VIN – 0.6
 ω
 ω
• exp – • arctan   • sinarctan  
 α
 α
L•ω
 ω

r + 1.5
2 •L
(r + 1.5)
1
–
L •C
4 • L2
2
ω=
where L is the inductance, r is the resistance of the
inductor and C is the output capacitance. For low DCR
inductors, which is usually the case for this application,
the peak inrush current can be simplified as follows:
IP =
The LED current is controlled by the feedback resistor (R1
in Figure 1) and the feedback reference voltage.
VIN – 0.6
 α π
• exp – • 
 ω 2
L•ω
The CTRL pin controls the feedback reference voltage as
shown in the Typical Performance Characteristics. For
CTRL higher than 1.8V, the feedback reference is 200mV,
which results in full LED current. CTRL pin can be used as
dimming control when CTRL voltage is between 200mV to
1.5V. In order to have accurate LED current, precision
resistors are preferred (1% is recommended). The formula and table for RFB selection are shown below.
RFB = 200mV/ILED-Full
(1)
Table 4. RFB Resistor Value Selection
FULL ILED (mA)
R1 (Ω)
5
40.0
10
20.0
15
13.3
20
10.0
The filtered PWM signal can be considered as an adjustable DC voltage. It can be used to adjust the CTRL voltage
source in dimming control. The circuit is shown in Figure␣ 6. The corner frequency of R1 C1 should be lower than
the freqency of the PWM signal. R1 needs to be much
smaller than the internal impedance in the CTRL pin, which
is 50kΩ.
LT3465/
LT3465A
R1
5k
PWM
C1
100nF
CTRL
3465A F06
Figure 6. Dimming Control Using a Filtered PWM Signal
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LT3465/LT3465A
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APPLICATIO S I FOR ATIO
Dimming Using Direct PWM (LT3465A)
Unlike the LT3465, the LT3465A does not have internal
soft-start. Although the input current is higher during startup, the absence of soft-start allows the CTRL pin to be
directly driven with a PWM signal for dimming. A zero
percent duty cycle sets the LED current to zero, while 100%
duty cycle sets it to full current. Average LED current
increases proportionally with the duty cycle of the PWM
signal. PWM frequency should be between 1kHz and 10kHz
for best performance. The PWM signal should be at least
1.8V in magnitude; lower voltage will lower the feedback
voltage as shown in Equation 1. Waveforms are shown for
a 1kHz PWM and 10kHz PWM signal in Figures 7a and 7b
respectively.
LT3465A
PWM
minimize the input current. VOUT and input current during
output open circuit are shown in the Typical Performance
Characteristics.
Board Layout Consideration
As with all switching regulators, careful attention must be
paid to the PCB board layout and component placement.
To maximize efficiency, switch rise and fall times are made
as short as possible. To prevent electromagnetic interference (EMI) problems, proper layout of the high frequency
switching path is essential. Place COUT next to the VOUT
pin. Always use a ground plane under the switching
regulator to minimize interplane coupling. In addition, the
ground connection for the feedback resistor R1 should be
tied directly to the GND pin and not shared with any other
component, ensuring a clean, noise-free connection. Recommended component placement is shown in Figure 8.
CTRL
GND
COUT
L
FB
100mV/DIV
RFB
1
6
2
5
3
4
CIN
VIN
CTRL
CTRL
2V/DIV
3465A F08
200µs/DIV (1kHz)
3465A F07a
Figure 8. Recommended Component Placement
Start-Up Input Current (LT3465A)
Figure 7a.
As previously mentioned, the LT3465A does not have an
internal soft-start circuit. Inrush current can therefore rise
to approximately 400mA as shown in Figure 9 when
driving 4 LEDs. The LT3465 has an internal soft-start
circuit and is recommended if inrush current must be
minimized.
FB
100mV/DIV
CTRL
2V/DIV
20µs/DIV (10kHz)
3465A F07b
Figure 7b.
Open-Circuit Protection
The LT3465 and LT3465A have an internal open-circuit
protection circuit. In the cases of output open circuit,
when the LEDs are disconnected from the circuit or the
LEDs fail, the VOUT is clamped at 30V. The LT3465 and
LT3465A will then switch at a very low frequency to
IIN
200mV/DIV
FB
200mV/DIV
CTRL
2V/DIV
50µs/DIV
3465A F09
Figure 9.
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LT3465/LT3465A
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TYPICAL APPLICATIO S
Li-Ion to Two White LEDs
L1
22µH
85
3V TO 5V
VIN = 3.6V
2 LEDs
80
75
VOUT
VIN
CIN
1µF
LT3465/
LT3465A
FB
CTRL
GND
COUT
1µF
EFFICIENCY (%)
SW
R1
4Ω
70
65
60
3465A TA01a
55
CIN: TAIYO YUDEN JMK107BJ105
COUT: AVX 0603ZD105
L1: MURATA LQH32CN220
LT3465
LT3465A
50
0
10
30
20
LED CURRENT (mA)
40
50
3465A TA01b
Li-Ion to Three White LEDs
L1
22µH
85
VIN = 3.6V
3 LEDs
3V TO 5V
80
VOUT
75
CIN
1µF
LT3465/
LT3465A
FB
CTRL
GND
COUT
0.22µF
R1
10Ω
EFFICIENCY (%)
SW
VIN
70
65
60
3465A TA02a
CIN: TAIYO YUDEN JMK107BJ105
COUT: AVX 0603YD224
L1: MURATA LQH32CN220
55
LT3465
LT3465A
50
0
5
15
10
LED CURRENT (mA)
20
3465A TA02b
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LT3465/LT3465A
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TYPICAL APPLICATIO S
Li-Ion to Five White LEDs
L1
22µH
3V TO 5V
SW
VOUT
VIN
CIN
1µF
LT3465/
LT3465A
FB
CTRL
GND
COUT
0.22µF
R1
10Ω
3465A TA03a
CIN: TAIYO YUDEN JMK107BJ105
COUT: TAIYO YUDEN GMK212BJ224
L1: MURATA LQH32CN220
85
VIN = 3.6V
5 LEDs
80
EFFICIENCY (%)
75
70
65
60
55
LT3465
LT3465A
50
0
5
15
10
LED CURRENT (mA)
20
3465A TA03b
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LT3465/LT3465A
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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
3465af
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
LT3465/LT3465A
U
TYPICAL APPLICATIO
Li-Ion to Six White LEDs
L1
47µH/22µH
85
VIN = 3.6V
6 LEDs
3V TO 5V
80
75
VOUT
CIN
1µF
LT3465/
LT3465A
CTRL
FB
GND
COUT
0.47µF
R1
10Ω
EFFICIENCY (%)
SW
VIN
70
65
60
3465A TA04a
CIN: TAIYO YUDEN JMK107BJ105
COUT: TAIYO YUDEN GMK212BJ474
L1: MURATA LQH32CN470 (LT3465)
L1: MURATA LQH32CN220 (LT3465A)
55
LT3465
LT3465A
50
0
5
15
10
LED CURRENT (mA)
20
3465A TA04b
RELATED PARTS
PART NUMBER DESCRIPTION
LT1618
Constant Current, Constant Voltage, 1.4MHz, High Efficiency
Boost Regulator
LT1932
Constant Current, 1.2MHz, High Efficiency White LED
Boost Regulator
LT1937
Constant Current, 1.2MHz, High Efficiency White LED
Boost Regulator
LTC®3200-5
Low Noise, 2MHz, Regulated Charge Pump White LED Driver
LTC3202
Low Noise, 1.5MHz, Regulated Charge Pump White LED Driver
LTC3205
LTC3405
LTC3405A
LTC3406
LTC3406B
LTC3407
LTC3411
LTC3412
LTC3440/
LTC3441
LT3466
COMMENTS
Up to 16 White LEDs, VIN: 1.6V to 18V, VOUT(MAX): 34V, IQ: 1.8mA,
ISHDN: <1µA, 10-Lead MS
Up to 8 White LEDs, VIN: 1V to 10V, VOUT(MAX): 34V, IQ: 1.2mA,
ISHDN: <1µA, ThinSOT
Up to 4 White LEDs, VIN: 2.5V to 10V, VOUT(MAX): 34V, IQ: 1.9mA,
ISHDN: <1µA, ThinSOT, SC70
Up to 6 White LEDs, VIN: 2.7V to 4.5V, IQ: 8mA, ISHDN: <1µA, ThinSOT
Up to 8 White LEDs, VIN: 2.7V to 4.5V, IQ: 5mA, ISHDN: <1µA,
10-Lead MS
Multi-Display LED Controller
92% Efficiency, VIN: 2.8V to 4.5V, IQ: 4.2mA, ISD: <1µA, QFN,
Drives Main, Sub, RGB
300mA (IOUT), 1.5MHz Synchronous Step-Down
95% Efficiency, VIN: 2.7V to 6V, VOUT(MIN): 0.8V, IQ: 20µA, ISHDN: <1µA,
DC/DC Converter
ThinSOT
600mA (IOUT), 1.5MHz Synchronous Step-Down
95% Efficiency, VIN: 2.5V to 5.5V, VOUT(MIN): 0.6V, IQ: 20µA,
DC/DC Converter
ISHDN: <1µA, ThinSOT
Dual 600mA (IOUT), 1.5MHz Synchronous Step-Down
95% Efficiency, VIN: 2.5V to 5.5V, VOUT(MIN): 0.6V, IQ: 40µA,
DC/DC Converters
ISHDN: <1µA, MS10E, DFN
1.25A (IOUT), 4MHz Synchronous Step-Down DC/DC Converter 95% Efficiency, VIN: 2.5V to 5.5V, VOUT(MIN): 0.8V, IQ: 60µA,
ISHDN: <1µA, MS10, DFN
2.5A (IOUT), 4MHz Synchronous Step-Down DC/DC Converter 95% Efficiency, VIN: 2.5V to 5.5V, VOUT(MIN): 0.8V, IQ: 60µA,
ISHDN: <1µA, TSSOP16E
600mA/1.2A (IOUT), 2MHz/1MHz Synchronous Buck-Boost
95% Efficiency, VIN: 2.5V to 5.5V, VOUT(MIN): 2.5V, IQ: 25µA,
DC/DC Converter
ISHDN: <1µA, 10-Lead MS
Full Function White LED Step-Up Converter with
Drives Up to 20 LEDs, Independent Step-Up Converters,
Built-In Schottkys
VIN: 2.7µV to 24V, DFN Package
3465af
12
Linear Technology Corporation
LT/TP 0504 1K • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2003