This application note describes how to implement a DALI (Digital Addressable Lighting Interface) in an existing high-frequency dimmable tube-lamp ballast application
This document details how to implement a Digital Addressable Lighting Interface (DALI) in an existing high-frequency dimmable tube-lamp ballast application. It focuses on the use of the ST7DALI-EVAL evaluation board, which features the ST7DALIF2 microcontroller to handle DALI communication while interfacing with the ballast controller.
The note covers the hardware architecture, including the interface between the microcontroller and the analog half-bridge controller. It explains the use of the DALI Communication Module (DCM) for efficient reception and transmission of DALI signals. Additionally, it provides considerations for power consumption, specifically regarding the microcontroller's power supply when the lamp is off, and includes schematics and a bill of materials for the evaluation board.
| Internal EEPROM | 256 bytes |
|---|---|
| Program memory | 3 Kbytes |
| Flash program memory | 8 Kbytes |
| PWM outputs | 4 |
| I/Os | Up to 15 |
| Clock source | Internal 1% RC oscillator |
| Power consumption (Halt Mode) | 170 mW |
It is an evaluation board that implements a DALI interface in an existing high-frequency dimmable tube-lamp ballast application.
It uses the DALI Communication Module (DCM) to decode forward frames and send backward frames without CPU overhead.
A 10 kohm resistor is recommended as a trade-off between low current consumption and noise immunity.