Datasheet Linear Technology LT1937

Manufacturer	Linear Technology
Series	LT1937

White LED Step-Up Converter in SC70 and ThinSOT

Datasheets

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PDF, 372 Kb, File uploaded: Oct 4, 2017

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Packaging

	LT1937ES5#PBF	LT1937ES5#TRMPBF	LT1937ES5#TRPBF	LT1937ESC6#PBF	LT1937ESC6#TRMPBF	LT1937ESC6#TRPBF
N	1	2	3	4	5	6
Package	SOT-23 Package Outline Drawing	SOT-23 Package Outline Drawing	SOT-23 Package Outline Drawing	SC-70 Package Outline Drawing	SC-70 Package Outline Drawing	SC-70 Package Outline Drawing
Package Code	S5	S5	S5	SC6	SC6	SC6
Package Index	05-08-1635	05-08-1635	05-08-1635	05-08-1638	05-08-1638	05-08-1638
Pin Count	5	5	5	6	6	6

Parametrics

Parameters / Models	LT1937ES5#PBF	LT1937ES5#TRMPBF	LT1937ES5#TRPBF	LT1937ESC6#PBF	LT1937ESC6#TRMPBF	LT1937ESC6#TRPBF
Architecture	Average Output Current Control	Average Output Current Control	Average Output Current Control	Average Output Current Control	Average Output Current Control	Average Output Current Control
Demo Boards	DC484A,DC507A	DC484A,DC507A	DC484A,DC507A	DC484A,DC507A	DC484A,DC507A	DC484A,DC507A
Design Tools	LTspice File	LTspice File	LTspice File	LTspice File	LTspice File	LTspice File
Dimming	PWM	PWM	PWM	PWM	PWM	PWM
Export Control	no	no	no	no	no	no
Frequency, kHz	1200	1200	1200	1200	1200	1200
Ishutdown, µA	1	1	1	1	1	1
Isupply, mA	1.9	1.9	1.9	1.9	1.9	1.9
Max Number of LEDs	4	4	4	4	4	4
Monolithic	yes	yes	yes	yes	yes	yes
Number of Outputs	1	1	1	1	1	1
Operating Temperature Range, °C	0 to 85	0 to 85	0 to 85	0 to 85	0 to 85	0 to 85
Switch Current, A	0.32	0.32	0.32	0.32	0.32	0.32
Synchronous	no	no	no	no	no	no
Topology	Boost, LED Driver	Boost, LED Driver	Boost, LED Driver	Boost, LED Driver	Boost, LED Driver	Boost, LED Driver
Vin Max, V	10	10	10	10	10	10
Vin Min, V	2.5	2.5	2.5	2.5	2.5	2.5
Vout Max, V	36	36	36	36	36	36

Eco Plan

	LT1937ES5#PBF	LT1937ES5#TRMPBF	LT1937ES5#TRPBF	LT1937ESC6#PBF	LT1937ESC6#TRMPBF	LT1937ESC6#TRPBF
RoHS	Compliant	Compliant	Compliant	Compliant	Compliant	Compliant

Design Notes

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White LED Driver in Tiny SC70 Package Delivers High Efficiency and Uniform LED Brightness &mdash DN315
PDF, 88 Kb, File published: Jul 1, 2003
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White LED Driver in Tiny SC70 Package Delivers High Efficiency
and Uniform LED Brightness вЂ“ Design Note 315
David Kim
Introduction
The LTВ®1937 step-up white LED driver is an ideal solution for small battery-powered portable devices such as
cellular phones, PDAs and digital cameras. The LT1937
features an internal 36V switch that is capable of driving up to eight LEDs in series, but it is optimized for
Li-Ion powered color display backlight applications that
use two to four white LEDs. The LT1937 guarantees a
constant light intensity and color in each LED, regardless of differences in their forward voltage drops due
to a constant current step-up architecture that directly
regulates the LED current. The constant 1.2MHz switching allows for the use of tiny external components and
minimizes input and output ripple voltageвЂ”meeting
the noise level requirements of products with sensitive
wireless circuitry. The superior internal compensation
of LT1937 lowers the output capacitor requirement to a
single 0.22ОјF ceramic, saving space and cost. The low
95mV feedback voltage and an efп¬Ѓcient internal switch
minimize power losses in the LT1937. The result is a
typical efп¬Ѓciency of 84%. The LT1937 is available in the
tiny SC70 or 1mm tall ThinSOTв„ў package.
Li-Ion Powered Driver for Three White LEDs
Figure 1 shows a white LED driver circuit that is …

Articles

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White LED Driver in Tiny SC70 Package Achieves 84% Efficiency &mdash LT Journal
PDF, 160 Kb, File published: Aug 9, 2004
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DESIGN IDEAS White LED Driver in Tiny SC70 Package
Achieves 84% Efficiency
by Pit-Leong Wong
Introduction
VIN
3VвЂ“5V L
22ВµH D 90
CIN
1ВµF VDC
DIMMING
VIN 85 SW
91k
5.1k LT1937
SHDN FB
R1
4.02в„¦ GND CIN: TAIYO YUDEN JMK107BJ105
COUT: AVX 0603YD224
D: CENTRAL CMDSH-3
L: MURATA LQH3C220 (408) 573-4150
(843) 946-0362
(516) 435-1110
(814) 237-1431 LT1937
FB D2 Figure 1. Li-Ion driver for …

Model Line

Series: LT1937 (6)

LT1937ES5#PBF LT1937ES5#TRMPBF LT1937ES5#TRPBF LT1937ESC6#PBF LT1937ESC6#TRMPBF LT1937ESC6#TRPBF

Manufacturer's Classification

Power Management > LED Driver ICs > Step-Up (Boost) LED Drivers