The LM3533 is a complete power source for backlight, keypad, and indicator LEDs in
smartphone handsets. The high-voltage inductive boost converter provides the power for two series
LED strings for display backlight and keypad functions (HVLED1 and HVLED2). The integrated charge
pump provides the bias for the five low-voltage indicator LED current sinks (LVLED1 to LVLED5). All
low-voltage current sinks can have a programmable pattern modulated onto their output current for a
wide variety of blinking patterns.
Additional features include a pulse width modulation (PWM) control input for content
adjustable backlight control (CABC), and an ambient light sensor interface (ALS) with an internal
8-bit ADC to provide automatic current adjustment based upon ambient light conditions. Both the PWM
and ALS inputs can be used to control any high- or low-voltage current sink.
The LM3533 is fully programmable via an I2C-compatible
interface. The device is available in a
20-pin DSBGA and operates over a 2.7-V to 5.5-V input voltage range and a −40°C to +85°C
temperature range.
The LM3533 is a complete power source for backlight, keypad, and indicator LEDs in
smartphone handsets. The high-voltage inductive boost converter provides the power for two series
LED strings for display backlight and keypad functions (HVLED1 and HVLED2). The integrated charge
pump provides the bias for the five low-voltage indicator LED current sinks (LVLED1 to LVLED5). All
low-voltage current sinks can have a programmable pattern modulated onto their output current for a
wide variety of blinking patterns.
Additional features include a pulse width modulation (PWM) control input for content
adjustable backlight control (CABC), and an ambient light sensor interface (ALS) with an internal
8-bit ADC to provide automatic current adjustment based upon ambient light conditions. Both the PWM
and ALS inputs can be used to control any high- or low-voltage current sink.
The LM3533 is fully programmable via an I2C-compatible
interface. The device is available in a
20-pin DSBGA and operates over a 2.7-V to 5.5-V input voltage range and a −40°C to +85°C
temperature range.