LP3933 Datasheet, PDF(14/18 Page) National Semiconductor (TI) – Lighting Management System for Six White LEDs and Two RGB or FLASH LEDs

English

English German Russian Spanish Italian Polish Chinese Japanese Korean French Portuguese	Language :

LP3933 Datasheet, PDF (14/18 Pages) National Semiconductor (TI) – Lighting Management System for Six White LEDs and Two RGB or FLASH LEDs

◁

RGB LED PWM Control (Note 15) (Continued)

RSW1

Enable for R1 switch

GSW1

Enable for G1 switch

BSW1

Enable for B1 switch

RSW2

Enable for R2 switch

GSW2

Enable for G2 switch

BSW2

Enable for B2 switch

RGB_START

Master Switch for both RGB Drivers:

RGB_START = 0 â RGB OFF

RGB_START = 1 â RGB ON, starts the new cycle from t = 0

RGB_PWM

RGB_PWM = 0 â RSW, GWS and BSW control directly the RGB outputs (on/off control only)

RGB_PWM = 1 â Normal PWM RGB functionality (duty, slope, on/off times, cycle)

EN_FLASH1

Flash Mode enable controls for RGB1 and RGB2. In Flash mode (EN_FLASH = 1) RGB outputs are

EN_FLASH2

PWM controlled simultaneously, not in 3-phase system as in the Normal Mode.

R1_PWM

G1_PWM

XX_PWM = 0 â External PWM control from PWM_LED pin is disabled

XX_PWM = 1 â External PWM control from PWM_LED pin is enabled

B1_PWM

R2_PWM

Internal PWM control (DUTY) can be used independently of external PWM control. External PWM has

the same effect on all enabled outputs.

G2_PWM

B2_PWM

PWM_LED input can be used as direct on/off or brightness (PWM) control. If PWM_LED input is not used, it must be tied to VDD_IO.

Note 15: Application Note 1291, âDriving RGB LEDs Using LP3933 Lighting Management Systemâ contains a thorough description of the RGB driver functionality

including programming examples.

WLED Driver (WLED1...4)

White LED (WLED) driver drives each white LED with a

regulated constant current. The amount of the current is

controlled by the 8-bit current mode DAC from 0 to 25.5mA

in 0.1mA steps.

20080527

CLED Driver (CLED1â¦2)

The current of CLEDs (Caller ID display backlight LEDs) can

be adjusted by 8-bit current mode DAC. WLED and CLED

can be used to drive any kind of LED.

20080504

Enables

WLED and CLED enable is controlled from user register.

PWM control of WLED and CLED (for dimming etc.) is

possible using PWM_LED pin together with WLED_PWM

and CLED_PWM enable control from user register.

www.national.com

▷