Getting Started

In most cases, the board ships mounted onto a battery pack. The battery pack holds three AAA size, conven-

tional alkaline batteries. When no battery pack is present, external power can be applied to the DC+ and DC-

terminals.

A jumper labeled J1 is inline with the battery supply terminal DC+ for connecting/disconnecting power. To apply

power to the board, connect the supply by jumpering ON, MCU. The red LED7 should illuminate, indicating that

power has been connected. There is an additional jumper labeled J2 that provides access to the EN/SET pin of

the AAT3174. Ensure that ON SRL is also jumpered so that the microcontroller is connected to the EN/SET pin.

The user interface is provided by three buttons: DATA, FLASH, and MOVIE. The modes of operation are detailed

in Table 1. The FLASH button generates a flash pulse. By default, the FLASH button generates a pulse at full

current. The MOVIE button toggles on/off movie mode illumination. The DATA button is used to set different cur-

rent levels. When the DATA button is held down, the MCU will auto-cycle through the available brightness level

settings after a short delay. Some functions require that multiple buttons are pressed and released together.

User Interface Functionality

Table 1: User Interface Functionality.

Description

DATA

Increments through the 16 data settings. Hold down to auto-cycle (does not

turn LED on, just sets data).

Generate flash pulse. Current level determined by the DATA setting (defaults

to DATA 1). Trim-pot VR4 sets duration.

MOVIE

Toggle on/off movie mode illumination. Current level determined by the DATA

setting. Leave on to see effects of changing DATA.

DATA + FLASH + MOVIE

Reset, shutdown.

EV-128

AAT3174 EVAL: High Current,

High Efficiency Charge Pump

2

EV-128.2006.04.1.0

1 The '+' sign indicates that these buttons are all pressed and released together

2. Flash pulse duration is adjustable from 10ms to 2 seconds. Rotate trim-pot VR4 clockwise to reduce the duration.