Backlight Drivers

LP5526 has 2 independent backlight drivers. Both drivers are regulated constant current sinks. LED current for both LED strings

are controlled by the 8-bit current mode DACs with 0.1 mA step. MAIN and SUB LEDs can be also controlled with one DAC

(MAIN) for better matching allowing the use of larger displays having up to 8 white LEDs by setting DISPL bit to 1.

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MAIN output for 4 LEDs (DISPL = 0)

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SUB output for 2 LEDs (DISPL = 0)

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MAIN and SUB outputs for 8 LEDs (DISPL = 1)

EXTERNAL PWM CONTROL

The GPIO[0]/PWM pin can be used to control the backlight drivers brightness or set leds on/off. External PWM control is enabled

by writing 1 to EN_MAIN_PWM and/or EN_SUB_PWM bits in register address 2BH. GPIO[0]/PWM pin is used as external PWM

input when EN_PWM_PIN is set high. PWM input is active high, i.e. LED is activated when in high state.

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