LT3476EUHF#PBF Linear Technology, LT3476EUHF#PBF Datasheet

IC LED DRVR HP CONST CURR 38-QFN

LT3476EUHF#PBF

Manufacturer Part Number
LT3476EUHF#PBF
Description
IC LED DRVR HP CONST CURR 38-QFN
Manufacturer
Linear Technology
Type
High Power, Constant Currentr
Datasheet

Specifications of LT3476EUHF#PBF

Constant Current
Yes
Topology
PWM, Step-Down (Buck), Step-Up (Boost)
Number Of Outputs
4
Internal Driver
Yes
Type - Primary
Automotive, Backlight
Type - Secondary
Color, RGB
Frequency
200kHz ~ 2MHz
Voltage - Supply
2.8 V ~ 16 V
Voltage - Output
2.2 V ~ 36 V
Mounting Type
Surface Mount
Package / Case
38-QFN
Operating Temperature
-40°C ~ 85°C
Current - Output / Channel
1.5A
Internal Switch(s)
Yes
Efficiency
96%
Led Driver Application
Automotive, Avionic Lighting
No. Of Outputs
4
Output Current
1.5A
Output Voltage
36V
Dimming Control Type
PWM
Rohs Compliant
Yes
Input Voltage
2.8V To 16V
Lead Free Status / RoHS Status
Lead free / RoHS Compliant

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
LT3476EUHF#PBFLT3476EUHF
Manufacturer:
LT
Quantity:
10 000
Company:
Part Number:
LT3476EUHF#PBFLT3476EUHF
Manufacturer:
LINEAR/凌特
Quantity:
20 000
Company:
Part Number:
LT3476EUHF#PBF
Manufacturer:
LINEAR/凌特
Quantity:
20 000
Company:
Part Number:
LT3476EUHF#PBF/I
Manufacturer:
LT
Quantity:
95
Company:
Part Number:
LT3476EUHF#PBFLT3476EUHF#TRPBF
Manufacturer:
LINEAR/凌特
Quantity:
20 000
APPLICATIO S
FEATURES
V
2.8V TO 16V
TYPICAL APPLICATIO
PV
IN
33V
8 LEDS
UP TO
IN
True Color PWM
Dimming Ratio (In Boost Confi guration)
LED Current Regulation with High-Side Sense
VADJ Pin Accurately Sets LED Current Sense
Threshold Over Range 10mV to 120mV
Four Independent Driver Channels with 1.5A, 36V
Internal NPN Switches
Frequency Adjust Pin: 200kHz to 2MHz
High Effi ciency Conversion = Up to 96%
Open LED Protection
Low Quiescent Current
Wide V
Thermally Enhanced, 38-Lead, 5mm × 7mm
QFN Package
RGGB Lighting
Automotive and Avionic Lighting
TFT LCD Backlighting
Constant-Current Sources
2.2μF
22mA in Active Mode
<10μA in Shutdown Mode
PWM1-4
SHDN
10μH
IN
100mΩ
1A
CAP1
LED1
Range: 2.8V to 16V
0.22μF
SW1
CAP1-4
LED1-4
V
PWM1-4
SHDN
IN
TM
U
100W Quad 1A
Dimming Delivers Up to 5000:1
0.22μF
SW2
10μH
100mΩ
1A
LT3476
GND
CAP2
LED2
U
×
SW3
8 LED Driver
10μH
100mΩ
1A
CAP3
LED3
0.22μF
VADJ1-4
VC1-4
3476 TA01
SW4
REF
R
T
0.22μF
21k
10μH
100mΩ
1A
CAP4
LED4
DESCRIPTIO
1.05V
The LT
to operate as a constant-current source for driving high
current LEDs. A fi xed frequency, current mode architecture
results in stable operation over a wide range of supply and
output voltages. A frequency adjust pin allows the user to
program switching frequency between 200kHz and 2MHz
to optimize effi ciency and external component size.
The LT3476 senses output current at the high side of
the LED. High side current sensing is the most fl exible
scheme for driving LEDs, allowing buck, boost or buck-
boost confi gurations. Each current monitor threshold is
trimmed to within 2.5% at the full scale of 105mV. With
an external sense resistor, the user programs the output
current range of each channel. Each of the four regulators
is independently operated by that channel’s PWM signal.
This PWM feature allows precise adjustment of the color
mixing or dimming ratio of the LED source. Dimming
ratios up to 1000:1 can be achieved.
True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are
the property of their respective owners.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
1nF
Quad Output LED Driver
®
4.99k
100k
3476 is a quad output DC/DC converter designed
2.2μF
× 4
500mA/DIV
U
5V/DIV
PWM
I
LED
1000:1 PWM Dimming at 100Hz
High Current
5μs/DIV
LT3476
3476 TA02
3476fa
1

Related parts for LT3476EUHF#PBF

LT3476EUHF#PBF Summary of contents

Page 1

... LED source. Dimming ratios up to 1000:1 can be achieved. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. × 8 LED Driver ...

Page 2

... Storage Temperature Range ................... –65°C to 125°C Lead Temperature ................................................. 300° ORDER I FOR ATIO LEAD FREE FINISH TAPE AND REEL LT3476EUHF#PBF LT3476EUHF#TRPBF LEAD BASED FINISH TAPE AND REEL LT3476EUHF LT3476EUHF#TR Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. ...

Page 3

ELECTRICAL CHARACTERISTICS temperature range, (Note 3) otherwise specifi cations are at T PWM1-4 = 3.3V REF , CAP1-4 = 5V, unless otherwise noted. ADJ1-4 PARAMETER Quiescent Current Idle Quiescent Current Active (Not Switching) Switching Frequency Nominal R Pin ...

Page 4

LT3476 W U TYPICAL PERFOR A CE CHARACTERISTICS V(CAP-LED) Threshold vs V ADJ 150 T = 25°C A 120 0.3 0.6 0.9 1.2 V (V) ADJ 3476 G01 V(CAP-LED) Threshold vs Temperature ...

Page 5

CTIO S VC1, VC4, VC3, VC2, (Pins 1, 12, 13, 38): Error Amplifi er Compensation Pin. When PWM is low, V compensation capacitor to save state for next cycle. LED1, LED2, LED3, LED4, (Pins 2, ...

Page 6

LT3476 W BLOCK DIAGRA R (EXT) SNS 0.1Ω 33V CAP SET 2kΩ V ADJ 1.25V 14, 15 – PWM 16, 17, 34, 35 IDLE MODE ...

Page 7

APPLICATIONS INFORMATION Layout Hints The high speed operation of the LT3476 demands careful attention to board layout. Several items are worthy of note. The exposed pad of the package is the only GND terminal of the IC and is also ...

Page 8

LT3476 U U APPLICATIO S I FOR ATIO will give better dimming control since for turning on the switch, the state of the PWM pin is sampled only during a narrow time slot at the beginning of each switch period. ...

Page 9

U U APPLICATIO S I FOR ATIO Ceramic type capacitors using X7R dielectric are best for temperature and DC bias stability of the capacitor value. All ceramic capacitors exhibit loss of capacitance value with increasing DC voltage bias ...

Page 10

LT3476 U U APPLICATIO S I FOR ATIO Programming the LED Current The LED Current is programmed using an external sense resistor in series with the load. This method allows fl ex- ibility in driving the load (i.e., sensing one ...

Page 11

... SIDES) RECOMMENDED SOLDER PAD LAYOUT 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. 350mA 350mA 10μ ...

Page 12

... True Color PWM, I < 1μA, OUT(MAX 13.5V, Dimming = 3000:1 True Color PWM, OUT(MAX) = 40V, Dimming = Analog/PWM, I OUT(MAX 40V, Dimming = Analog/PWM, I OUT(MAX 0707 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2006 < 1μA, SD < 1μA, QFN < 1μA, DFN 3476fa ...

Related keywords