AW3648

Jan 2018 V1.4

www.awinic.com.cn

17

Copyright © 2016 SHANGHAI AWINIC TECHNOLOGY CO., LTD

IN

I

HWEN

Fig 40

Power-Up Sequence with HWEN Driven by GPIO

FLASH MODE

In Flash Mode, the LED current source provides 64 target current levels from 23.4mA to 1.5A. The Flash

current are adjusted via the LED Flash Brightness Registers.

Flash mode is activated by the Enable

Register(setting M1, M0 to '11'), or by pulling the STROBE pin HIGH when the pin is enabled (Enable

Register). Once the Flash sequence is activated the current source ramps up to the programmed Flash

current by stepping through all current steps until the programmed current is reached.

When the device is enabled in Flash Mode through the Enable Register, all mode bits in the Enable Register

are cleared after a flash timeout event.

TORCH MODE

In Torch mode, the LED current source provides 64 target current levels from 5.4mA to 376mA. The Torch

currents are adjusted via the LED Torch Brightness Registers. Torch mode is activated by the Enable

Register (setting M1, M0 to '10'), or by pulling the TORCH/TEMP pin HIGH when the pin is enabled (Enable

Register) and set to Torch Mode. Once the TORCH sequence is activated the active current source ramps up

to the programmed Torch current by stepping through all current steps until the programmed current is

reached. The rate at which the current ramps is determined by the value chosen in the Timing Register.

Torch Mode is not affected by Flash Timeout or by a TX Interrupt event.

IR MODE

In IR Mode, the target LED current is equal to the value stored in the LED Flash Brightness Registers. When

IR mode is enabled (setting M1, M0 to '01'), the boost converter turns on and set the output equal to the input

(pass-mode). At this point, toggling the STROBE pin enables and disables the LED current source (if enabled).

The strobe pin can only be set to be Level sensitive, meaning all timing of the IR pulse is externally controlled.

In IR Mode, the current sources do not ramp the LED outputs to the target. The current transitions

immediately from off to on and then on to off.