http://www.datasheet4u.com

900,000+ Datasheet PDF Search and Download

Datasheet4U offers most rated semiconductors datasheets pdf




Linear Technology Electronic Components Datasheet

LT3490 Datasheet

Single Cell 350mA LED Driver

No Preview Available !

LT3490 pdf
LTC3490
Single Cell 350mA
LED Driver
FEATURES
350mA Constant Current Output
2.8V to 4V Output Compliance
1- or 2-Cell NiMH or Alkaline Input
Synchronous Rectification: Up to 90% Efficiency
Fixed Frequency Operation: 1.3MHz
Low Quiescient Current: <1mA
Very Low Shutdown Current: <50µA
Open LED Output Limited to 4.7V
VIN Range: 1V to 3.2V
Dimming Control
Undervoltage Lockout to Protect Batteries
Low Profile (0.75mm) 3mm × 3mm Thermally
Enhanced 8-Lead DD and S8 Packages
U
APPLICATIO S
Portable Lighting
Rechargeable Flashlights
DESCRIPTIO
The LTC®3490 provides a constant current drive for 1W
LED applications. It is a high efficiency boost converter
that operates from 1 or 2 NiMH or alkaline cells and
generates 350mA of constant current with up to 4V of
compliance. It contains a 100mNFET switch and a
130mPFET synchronous rectifier. The fixed switching
frequency is internally set to 1.3MHz.
The LTC3490 limits the output voltage to 4.7V if the output
load is disconnected. It also features an analog dimming
capability that reduces the drive current proportional to
the CTRL/SHDN pin voltage. A low-battery logic output
signals when the battery has dropped below 1V/cell. An
undervoltage lockout circuit shuts down the LTC3490
when the battery voltage drops below 0.85V/cell. The
feedback loop is internally compensated to minimize com-
ponent count.
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATIO
Single Cell Minimum Component LED Driver
3.3µH
1 NiMH OR +
ALKALINE
CELL
VIN SW
ON/OFF
CAP
LTC3490
350mA
CTRL/SHDN LED
CELLS LOBAT
1M
GND
4.7µF
HIGH
CURRENT
LED
3490 TA01
Efficiency vs VIN at VLED = 3.5V
100
IOUT = 350mA
90
80
70
60
50
40
30
20
10
0
1 1.5
2
VIN (V)
2.5 3
3490 TA02
3490f
1


Linear Technology Electronic Components Datasheet

LT3490 Datasheet

Single Cell 350mA LED Driver

No Preview Available !

LT3490 pdf
LTC3490
ABSOLUTE AXI U RATI GS (Note 1)
Supply Voltage (VIN) ................................... – 0.3V to 6V
Input Voltages (CTRL/SHDN, CELLS) ......... – 0.3V to 6V
Output Voltages (CAP, LED, SW) ................ – 0.3V to 6V
Operating Temperature Range (Note 2) .. – 40°C to 85°C
Storage Temperature Range ................. – 65°C to 125°C
Lead Temperature (Soldering, 10 sec, S8) .......... 300°C
UW U
PACKAGE/ORDER I FOR ATIO
TOP VIEW
CELLS 1
8 CTRL/SHDN
VIN 2 9 7 LOBAT
SW 3
6 CAP
GND 4
5 LED
ORDER PART
NUMBER
LTC3490EDD
DD PACKAGE
8-LEAD (3mm × 3mm) PLASTIC DFN
TJMAX = 125°C, θJA = 43°C/ W (NOTE 4)
EXPOSED PAD (PIN 9) IS GND
MUST BE SOLDERED TO PCB (NOTE 5)
DD PART MARKING
LBRQ
Consult LTC Marketing for parts specified with wider operating temperature ranges.
TOP VIEW
CELLS 1
VIN 2
SW 3
GND 4
8 CTRL/SHDN
7 LOBAT
6 CAP
5 LED
S8 PACKAGE
8-LEAD PLASTIC SO
TJMAX = 125°C, θJA = 150°C/ W (NOTE 4)
ORDER PART
NUMBER
LTC3490ES8
S8 PART MARKING
3490
ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating
temperature range, otherwise specifications are TA = 25°C. VIN = 2.5V unless otherwise specified.
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX
VIN Input Supply Range
1 3.2
VIN(START) Minimum Start-Up Voltage
(Note 3)
0.9 1
ILED(MAX) LED Drive Current
VCTRL/SHDN = VIN, DD Package
25°C to 85°C
– 40°C to <25°C
330 350 370
310 350 385
VCTRL/SHDN = VIN, S8 Package
25°C to 85°C
– 40°C to <25°C
337 350 363
325 345 365
ILED(SHDN) LED Drive Current in Shutdown
VCTRL/SHDN = 0V
0.1 1
VLED Output Compliance Voltage
2.8
4
VLED(OVL) Output Voltage Overvoltage Limit
Open LED
4.2
4.7
IIN(SHDN) Input Current, Shutdown
VCTRL/SHDN = 0V, Excluding Switch Leakage
20 50
IIN(ACTIVE) Input Current, Active
Excluding Load Power
20 30
fSW Switching Frequency
1.0 1.3 1.6
IL(NMOS) Leakage Current, NMOS Switch
0.1
RON(NMOS) On Resistance, NMOS Switch
IL(PMOS) Leakage Current, PMOS Switch
0.1
0.1
RON(PMOS) On Resistance, PMOS Switch
0.13
VIH Input High (CELLS)
VIN – 0.4
Input High (SHDN)
VIN • 0.9
VIL Input Low (CELLS)
0.4
Input Low (SHDN)
VIN • 0.2
2
UNITS
V
V
mA
mA
mA
mA
µA
V
V
µA
mA
MHz
µA
µA
V
V
V
V
3490f


Part Number LT3490
Description Single Cell 350mA LED Driver
Maker Linear Technology
Total Page 12 Pages
PDF Download
LT3490 pdf
Download PDF File
[partsNo] view html
View PDF for Mobile






Related Datasheet

1 LT3490 Single Cell 350mA LED Driver Linear Technology
Linear Technology
LT3490 pdf
2 LT3491 White LED Driver Linear Technology
Linear Technology
LT3491 pdf
3 LT3492 Triple Output LED Driver Linear Technology
Linear Technology
LT3492 pdf
4 LT3493 750kHz Step-Down Switching Regulator Linear Technology
Linear Technology
LT3493 pdf
5 LT3493-3 750kHz Step-Down Switching Regulator Linear Technology
Linear Technology
LT3493-3 pdf
6 LT3494 Micropower Low Noise Boost Converters Linear Technology
Linear Technology
LT3494 pdf
7 LT3494A Micropower Low Noise Boost Converters Linear Technology
Linear Technology
LT3494A pdf
8 LT3495 650mA/350mA Micropower Low Noise Boost Converter Linear Technology
Linear Technology
LT3495 pdf
9 LT3495-1 650mA/350mA Micropower Low Noise Boost Converter Linear Technology
Linear Technology
LT3495-1 pdf






Part Number Start With

0    1    2    3    4    5    6    7    8    9    A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    X    Y    Z

site map

webmaste! click here

contact us

Buy Components