LM3492MH Datasheet, PDF (1/24 Pages) Texas Instruments – Two-Channel Individual Dimmable LED Driver with Boost Converter and Fast Current Regulator

LM3492, LM3492Q
www.ti.com
SNVS656C – SEPTEMBER 2010 – REVISED MAY 2013
Two-Channel Individual Dimmable LED Driver with Boost Converter and Fast Current
Regulator
Check for Samples: LM3492, LM3492Q
FEATURES
1
•2 Boost Converter:
– LM3492Q is an Automotive Grade Product
that is AEC Q100 Grade 1 Qualified
– Very Wide Input Voltage Ranged from 4.5V-
65V
– Programmable Soft-start
– No Loop Compensation Required
– Stable with Ceramic and Other low ESR
Capacitors with no Audible Noise
– Nearly Constant Switching Frequency
Programmable from 200 kHz to 1 MHz
• Current Regulators:
– Programmable LED Current from 50 mA to
200 mA
– 1000:1 Contrast Ratio at a Dimming
Frequency of more than 3 kHz, Minimum
LED Current Pulse width is 300 ns
– Two Individual Dimmable LED strings up to
65V, total 15W (typically 28 LEDs at 150
mA)
– Dynamic Headroom Control maximizes
efficiency
– Over-Power protection
– ±3% current accuracy
• Supervisory Functions:
– Precision enable
– COMM I/O pin for diagnostic and
commands
– Thermal shutdown protection
– Thermally enhanced 20-Pin HTSSOP
package
APPLICATIONS
• Ultra-high contrast ratio 6.5”-10” LCD display
backlight up to 28 LEDs
• Automotive or marine GPS display
DESCRIPTION
The LM3492 integrates a boost converter and a two-
channel current regulator to implement a high efficient
and cost effective LED driver for driving two
individually dimmable LED strings with a maximum
power of 15W and an output voltage of up to 65V.
The boost converter employs a proprietary Projected-
On-Time control method to give a fast transient
response with no compensation required, and a
nearly constant switching frequency programmable
from 200 kHz to 1 MHz. The application circuit is
stable with ceramic capacitors and produces no
audible noise on dimming. The programmable peak
current limit and soft-start features reduce current
surges at startup, and an integrated 190 mΩ, 3.9A N-
Channel MOSFET switch minimizes the solution size.
TYPICAL APPLICATION
1
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2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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