Getting Started

In most cases, the AAT2803 evaluation board ships mounted onto a battery pack. The battery pack holds three

AAA size, conventional alkaline batteries. A jumper is inline with the battery supply for connecting/disconnect-

ing power. There are three other jumpers labeled LT, MV, and FL. They provide access to EN/SET, EN_FL, and

EN3, respectively. To apply power to the board, connect the supply by jumpering ON, MCU. The red LED7

should illuminate, indicating that power has been connected. Ensure that LT, MV, and FL are jumpered so that

the microcontroller can control the parts.

The user interface is provided by three buttons. The buttons are LIGHT, MOVIE, and FLASH. The modes of

operation are detailed in Table 1. Each button handles a particular function. The LIGHT button controls the

backlight section. When the LIGHT button is held down, the MCU will auto-cycle through the available bright-

ness level settings after a short delay. The MOVIE button toggles on/off the movie mode illumination. The

FLASH button provides a flash pulse and a red-eye reduction function. When the FLASH button is held down,

red-eye reduction mode will be executed after a short delay.

Table 1: User Interface Functionality.

Button(s) Pushed

1

Description

LIGHT

Increment the number of EN/SET edges. Toggles through the available brightness

level settings for the backlighting section. If held down, auto-cycle through the

settings.

MOVIE

Toggle on/off movie mode illumination.

FLASH

Press once to produce a ~300ms flash pulse. Hold down to produce a sequence of

red-eye reduction pulses.

LIGHT + FLASH

Decrement the number of EN/SET edges. Toggles through the available bright-

ness level settings for the backlighting section. If held down, auto-cycle through

the settings.

LIGHT + MOVIE

Increment the address. Cycles through addresses 1, 2, and 3 (i.e., main/sub, main-

only, sub-only).

MOVIE + FLASH

Switch to the next current level scale. Cycles through the 20mA, 30mA, 15mA, and

Low Current scales.

LIGHT + MOVIE + FLASH

Reset. All enable lines are pulled low.

EV-114

AAT2803 EVAL: Six-Channel White LED

Backlight Charge Pump with Flash

2

EV-114.2005.06.1.0

1. The + sign indicates that the specified buttons are all pressed and released together.