AN809
Digitally Addressable DALI Dimming Ballast
Authors:
Ross Fosler
Microchip Technology Incorporated
Cecilia Contenti
International Rectifier
Tom Ribarich
International Rectifier
INTRODUCTION
This reference design is a high efficiency, high power
factor and digital dimming electronic ballast designed to
drive rapid start fluorescent lamp types. The design
contains an active power factor correction circuit for
universal voltage input as well as a ballast control cir-
cuit using the IR2159. The design also includes a
PIC16F628 microcontroller and an isolation circuit for
connecting to a Digitally Addressable Lighting Interface
(DALI). Other features include EMI filtering, transient
protection and lamp FAULT protection.
International Rectifier (IR) and Microchip Technology
Inc. worked together to design a DALI type ballast. An
application note is provided here, and the correspond-
ing reference design is available from IR (see page 10
for ordering information).
This document describes many of the details within the
design of the ballast and some of the basics to DALI.
However, this document does not describe all the
details contained within the DALI specification. The
reader should be familiar with DALI and international
standard EN60929.
FIGURE 1: DALI DIMMING BALLAST
Features
• Lamp Type: 1X 36W T8 Lamp (IRPLDIM2E)
• 1X 32W T8 Lamp (IRPLDIM2U)
• Line Input: 185-265 VAC/50Hz (IRPLDIM2E)
• 90-140 VAC/60Hz (IRPLDIM2U)
• Interface DALI (2 wires)
• High Power Factor/Low THD
• High Frequency Operation
• Programmable Lamp Filament Preheating
• Programmable Ignition
• High precision Digital Dimming
• Logarithmic Dimming
• Diagnostic and FAULT Control
• Lamp FAULT Protection
• Brown-out Protection
• IR2159 HVIC Ballast Controller
• PIC16F628 Microcontroller
• Optically Isolated Communications
• Low Power Standby Mode
© 2002 Microchip Technology Inc.
DS00809B-page 1
