LT3592
1
3592fc
TYPICAL APPLICATION
FEATURES
APPLICATIONS
DESCRIPTION
500mA Wide Input Voltage
Range Step-Down LED Driver
with 10:1 Dimming
The LT
®
3592 is a fi xed frequency step-down DC/DC con-
verter designed to operate as a constant-current source.
An external sense resistor monitors the output current
allowing accurate current regulation, ideal for driving
high current LEDs. The output current can be dimmed
by a factor of 10 using an external signal for nighttime
brake lights.
The high switching frequency offers several advantages by
permitting the use of a small inductor and small ceramic
capacitors. Small components combined with the LT3592’s
10-pin DFN leadless surface mount package save space and
cost versus alternative solutions. The constant switching
frequency combined with low-impedance ceramic capaci-
tors result in low, predictable output ripple.
A wide input voltage range of 3.6V to 36V makes the
LT3592 useful in a variety of applications. Current mode
PWM architecture provides fast transient response and
cycle-by-cycle current limiting. Thermal shutdown provides
additional protection.
50/500mA Two Series Red LED Driver
n
Wide Input Voltage Range
Operation from 3.6V to 36V
n
Resistor Adjustable 400kHz–2.2MHz Switching
Frequency
n
Shorted and Open LED Protected
n
Internal Switch Current Sense Resistor
n
External Resistor Programs LED Current, Pin
Selects 10:1 Ratio
n
50mA/500mA LED Current Settings
n
Catch Diode Current Sense to Prevent Runaway at
High V
IN
n
Small Thermally Enhanced 10-Lead DFN
(2mm × 3mm) and MSOP-10 Packages
n
Automotive Signal Lighting
n
Industrial Lighting
n
Constant-Current, Constant Voltage Supplies
Effi ciency for 2 Red LEDs, L = 10μH, 900kHz
10µH
51k
3592 TA01a
4.7µF
1
µF
0.4Ω
10k
0.1µF
V
IN
SHDN
BRIGHT
R
T
BOOST
SW
DA
CAP
OUT
V
FB
LT3592
GND
ON
BRAKE
140k
900kHz
+
200/20mV
V
IN
7V TO 32V
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
INPUT VOLTAGE (V)
4
EFFICIENCY (%)
100
95
90
60
75
70
65
80
85
55
50
2012 24
3592 TA01b
28168
BRIGHT 500mA
LT3592
2
3592fc
ABSOLUTE MAXIMUM RATINGS
V
IN
, BRIGHT Voltages ................................ –0.3V to 36V
BOOST Voltage .........................................................60V
BOOST above SW pin ...............................................30V
CAP, OUT Voltages (OUT ≤ CAP) ...............................30V
V
FB
Voltage .................................................................4V
R
T
Voltage ...................................................................6V
(Note 1)
TOP VIEW
DDB PACKAGE
10-LEAD (3mm s 2mm) PLASTIC DFN
10
11
9
6
7
8
4
5
3
2
1
V
FB
OUT
CAP
BOOST
SW
R
T
BRIGHT
SHDN
V
IN
DA
θ
JA
= 76°C/W, θ
JC
= 13.5°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
1
2
3
4
5
R
T
BRIGHT
SHDN
V
IN
DA
10
9
8
7
6
11
V
FB
OUT
CAP
BOOST
SW
TOP VIEW
MSE PACKAGE
10-LEAD PLASTIC MSOP
θ
JA
= 38°C/W, θ
JC
= 8°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
PIN CONFIGURATION
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LT3592EDDB#PBF LT3592EDDB#TRPBF LDCQ
10-Lead (3mm × 2mm) Plastic DFN
–40°C to 125°C
LT3592IDDB#PBF LT3592IDDB#TRPBF LDCQ
10-Lead (3mm × 2mm) Plastic DFN
–40°C to 125°C
LT3592EMSE#PBF LT3592EMSE#TRPBF LTDCR 10-Lead Plastic MSOP –40°C to 125°C
LT3592IMSE#PBF LT3592IMSE#TRPBF LTDCR 10-Lead Plastic MSOP –40°C to 125°C
LEAD BASED FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE
LT3592EDDB LT3592EDDB#TR LDCQ
10-Lead (3mm × 2mm) Plastic DFN
–40°C to 125°C
LT3592IDDB LT3592IDDB#TR LDCQ
10-Lead (3mm × 2mm) Plastic DFN
–40°C to 125°C
LT3592EMSE LT3592EMSE#TR LTDCR 10-Lead Plastic MSOP –40°C to 125°C
LT3592IMSE LT3592IMSE#TR LTDCR 10-Lead Plastic MSOP –40°C to 125°C
Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi ed by a label on the shipping container.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifi cations, go to:
http://www.linear.com/tapeandreel/
SHDN Voltage ............................................................V
IN
DA Pin Current (Average) ..................... –1.2A (sourcing)
Operating Temperature Range (Notes 2, 3)
LT3592E ............................................. –40°C to 125°C
LT3592I .............................................. –40°C to 125°C
Storage Temperature Range ................... –65°C to 150°C
LT3592
3
3592fc
ELECTRICAL CHARACTERISTICS
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 LT3592E is guaranteed to meet performance specifi cations
from 0°C to 125°C junction temperature. Specifi cations over the –40°C
to 125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LT3592I is guaranteed over the full –40°C to 125°C operating junction
temperature range. The operating lifetime is derated at junction
temperatures greater than 125°C.
PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Input Voltage
l
3.25 3.6 V
Input Quiescent Current in Shutdown Not Switching
V
SHDN
= 0.3V
2
0.1
3
2
mA
µA
CAP to OUT Voltage 0.4 CAP to OUT
BRIGHT = 1.4V
BRIGHT = 0.3V
l
l
190
18
200
20
210
22
mV
mV
DA Pin Current to Stop OSC –0.8 –1 –1.2 A
Switching Frequency R
T
= 357k
R
T
= 140k
R
T
= 48.7k
350
800
1.9
400
900
2.2
450
1000
2.5
kHz
kHz
MHz
Maximum Duty Cycle R
T
= 140k 90 94 %
SHDN Input High Voltage 2.3 V
SHDN Input Low Voltage 0.3 V
BRIGHT Input High Voltage 1.4 V
BRIGHT Input Low Voltage 0.3 V
Switch Current Limit (Note 4)
l
0.85 1.25 1.5 A
Switch V
CESAT
I
SW
= 500mA 300 mV
Boost Pin Current I
SW
= 500mA 20 30 mA
Switch Leakage Current 110 µA
Minimum Boost Voltage (V
BOOST
– V
IN
)V
OUT
= 4V 1.8 2.5 V
Boost Diode Forward Voltage I
DIO
= 50mA 800 mV
V
FB
Voltage OUT = CAP = 4V, Bright = 12V
l
1.185 1.21 1.235 V
V
FB
Input Leakage Current V
FB
= 1.21V
l
–250 250 nA
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
A
= 25°C. V
IN
= 12V, V
BOOST
= 16V, V
OUT
= 4V unless otherwise noted. (Note 2)
Note 3: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed the maximum operating junction temperature
when overtemperature protection is active. Continuous operation above
the specifi ed maximum operating junction temperature may result in
device degradation or failure.
Note 4: Switch Current Measurements are performed when the outputs
are not switching. Slope compensation reduces current limit at higher duty
cycles.

LT3592IDDB#TRMPBF

Mfr. #:
Manufacturer:
Analog Devices / Linear Technology
Description:
LED Lighting Drivers 500mA Wide Input Voltage Range Step-Down LED Driver with 10:1 Dimming
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
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