The Figure 7-20 shows the main
state machine of the LED driver.
- INITIAL: The device enters
into INITIAL after VCC power up.
- STANDBY: The device enters
into STANDBY state from INITIAL when Chip_EN is set to 1. The device can
also enter into STANDBY from NORMAL when no LED is effective, or Stop_cmd is
received, or from OFAF when LSD_Clear = 1.
- NORMAL: The device enters
NORMAL state from STANDBY when one or more LEDs are effective: for manual
mode, at least one LED is enable (PWM and DC setting is not 0); for
autonomous mode, at lease one LED is enable and Start_cmd is received.
- OFAF: The device enters OFAF
(one fail all fail) state when LED short is detected and LSD_Action =1. In
OFAF mode, all LEDs are turned off. Once LSD_Clear is writen to 1, the
device enters back to STANDBY state.