Datasheet Linear Technology LT3797

Manufacturer	Linear Technology
Series	LT3797

Triple Output LED Driver Controller

Datasheets

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PDF, 451 Kb, Revision: B, File uploaded: Oct 4, 2017

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Packaging

	LT3797ELXE#PBF	LT3797EUKG#PBF	LT3797EUKG#TRPBF	LT3797ILXE#PBF	LT3797IUKG#PBF	LT3797IUKG#TRPBF
N	1	2	3	4	5	6
Package	7mm x 7mm LQFP-48 Package Outline Drawing	7x8 QFN-52 Package Outline Drawing	7x8 QFN-52 Package Outline Drawing	7mm x 7mm LQFP-48 Package Outline Drawing	7x8 QFN-52 Package Outline Drawing	7x8 QFN-52 Package Outline Drawing
Package Code	LXE	UKG	UKG	LXE	UKG	UKG
Package Index	05-08-1927	05-08-1874	05-08-1874	05-08-1927	05-08-1874	05-08-1874
Pin Count	48	52	52	48	52	52

Parametrics

Parameters / Models	LT3797ELXE#PBF	LT3797EUKG#PBF	LT3797EUKG#TRPBF	LT3797ILXE#PBF	LT3797IUKG#PBF	LT3797IUKG#TRPBF
Architecture	Constant Frequency Current Mode	Constant Frequency Current Mode	Constant Frequency Current Mode	Constant Frequency Current Mode	Constant Frequency Current Mode	Constant Frequency Current Mode
Demo Boards	DC1784A,DC2218A,DC1784B	DC1784A,DC2218A,DC1784B	DC1784A,DC2218A,DC1784B	DC1784A,DC2218A,DC1784B	DC1784A,DC2218A,DC1784B	DC1784A,DC2218A,DC1784B
Design Tools	LTspice File	LTspice File	LTspice File	LTspice File	LTspice File	LTspice File
Dimming	3000:1 PWM	3000:1 PWM	3000:1 PWM	3000:1 PWM	3000:1 PWM	3000:1 PWM
Export Control	no	no	no	no	no	no
Features	Rail-to-Rail Current Sense, Open LED Protection, Resistor Set Frequency, External Synchronization	Rail-to-Rail Current Sense, Open LED Protection, Resistor Set Frequency, External Synchronization	Rail-to-Rail Current Sense, Open LED Protection, Resistor Set Frequency, External Synchronization	Rail-to-Rail Current Sense, Open LED Protection, Resistor Set Frequency, External Synchronization	Rail-to-Rail Current Sense, Open LED Protection, Resistor Set Frequency, External Synchronization	Rail-to-Rail Current Sense, Open LED Protection, Resistor Set Frequency, External Synchronization
Frequency, kHz	1000	1000	1000	1000	1000	1000
Ishutdown, µA	0.1	0.1	0.1	0.1	0.1	0.1
Isupply, mA	0.5	0.5	0.5	0.5	0.5	0.5
Max Number of LEDs	25+	25+	25+	25+	25+	25+
Monolithic	no	no	no	no	no	no
Number of Outputs	3	3	3	3	3	3
Operating Temperature Range, °C	0 to 85	0 to 85	0 to 85	-40 to 85	-40 to 85	-40 to 85
Output Current, A	5	5	5	5	5	5
Switch Current, A	20	20	20	20	20	20
Synchronous	no	no	no	no	no	no
Topology	Buck, Boost, Buck-Boost, Sepic, LED Driver	Buck, Boost, Buck-Boost, Sepic, LED Driver	Buck, Boost, Buck-Boost, Sepic, LED Driver	Buck, Boost, Buck-Boost, Sepic, LED Driver	Buck, Boost, Buck-Boost, Sepic, LED Driver	Buck, Boost, Buck-Boost, Sepic, LED Driver
Vin Max, V	40	40	40	40	40	40
Vin Min, V	2.5	2.5	2.5	2.5	2.5	2.5
Vout Max, V	100	100	100	100	100	100

Eco Plan

	LT3797ELXE#PBF	LT3797EUKG#PBF	LT3797EUKG#TRPBF	LT3797ILXE#PBF	LT3797IUKG#PBF	LT3797IUKG#TRPBF
RoHS	Compliant	Compliant	Compliant	Compliant	Compliant	Compliant

Articles

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Boost-then-Buck LED Drivers Enable Wide PWM Dimming Range with Wide-Ranging Input Voltages (LT3797) &mdash LT Journal
PDF, 218 Kb, File published: Apr 9, 2014
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Boost-thenвЂ‘Buck LED Drivers Enable Wide PWM Dimming
Range with Wide-Ranging Input Voltages
Keith Szolusha and Taffy Wong Multichannel LED drivers are primarily designed to power
multiple LEDs or multiple LED strings, sometimes of different
colors or lengths, from a single IC. These drivers, however,
include a number of features that allow for other compelling
uses. The LT3797 3-channel LED driver, for instance, can
be configured to produce boost-then-buck capability with
one channel as a boost voltage preregulator while the other
two channels are configured as buck mode LED drivers.
When the input voltage source is wideranging and can be both above and below
the LED string rating, a buck-boost or
SEPIC topology is commonly used. These compared to buck-only converters, and
lower efficiency and higher conducted
EMI compared to boost-only regulators.
One way to avoid these problems is to
boost a wide-ranging input with a voltage preregulator and use that as the input
to a buck-only LED driver. This has the
advantages of step-up and step-down,
high PWM dimming bandwidth, and
lower conducted EMI. Since the LT3797
has three channels that can be used
for either voltage regulation or driving …

Model Line

Series: LT3797 (6)

LT3797ELXE#PBF LT3797EUKG#PBF LT3797EUKG#TRPBF LT3797ILXE#PBF LT3797IUKG#PBF LT3797IUKG#TRPBF

Manufacturer's Classification

Power Management > LED Driver ICs > Buck-Boost LED Drivers | Multitopology LED Driver | Step-Up (Boost) LED Drivers | Step-Down (Buck) LED Drivers