LM3532 Datasheet, PDF (1/45 Pages) Texas Instruments – High Efficiency White LED Driver with Programmable Ambient Light Sensing Capability and I2C-Compatible Interface

LM3532
High Efficiency White LED Driver with Programmable Ambient Light
Sensing Capability and I2C-Compatible Interface
General Description
The LM3532 is a 500 kHz fixed frequency asynchronous
boost converter which provides the power for 3 high-voltage,
low-side current sinks. The device is programmable over an
I²C-compatible interface and has independent current control
for all three channels. The adaptive current regulation method
allows for different LED currents in each current sink thus al-
lowing for a wide variety of backlight + keypad applications.
The main features of the LM3532 include dual ambient light
sensor inputs each with 32 internal voltage setting resistors,
8-bit logarithmic and linear brightness control, dual external
PWM brightness control inputs, and up to 1000:1 dimming
ratio with programmable fade in and fade out settings.
The LM3532 is available in a 16-bump, 0.4mm pitch thin micro
SMD (1.745 mm x 1.845 mm x 0.6 mm). The device operates
over a 2.7V to 5.5V input voltage range and the −40°C to +85°
C temperature range.
Typical Application Circuit
Features
● ^{Drives up to 3 Parallel High-Voltage LED Strings at 40V}
each with up to 90% efficiency
● ^{0.4% Typical Current Matching Between Strings}
● ^{256 Level Logarithmic and Linear Brightness Control with}
14-Bit Equivalent Dimming
● ^{I2C-compatible Interface}
● ^{Direct Read Back of Ambient Light Sensor via 8-bit ADC}
● ^{Programmable Dual Ambient Light Sensor Inputs with}
Internal Sensor Gain Selection
● ^{Dual External PWM Inputs for LED Brightness Adjustment}
● ^{Independent Current String Brightness Control}
● ^{Programmable LED Current Ramp Rates}
● ^{40V Over-Voltage Protection}
● ^{1A Typical Current Limit}
Applications
● ^{Power Source for White LED Backlit LCD Displays}
● ^{Programmable Keypad Backlight}
301154100
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.
301154 SNVS653B
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