Cirrus Logic AN402 - Manual (Page 3)

AN402
3
1. INTRODUCTION
The CS1615A is a 120VAC quasi-resonant buck-boost mode dimmable LED controller IC. The CS1615A uses a
digital control algorithm that is optimized for high efficiency and > 0.90 power factor over an input voltage range
(108VAC -132VAC). The CS1615A integrates a dimmer compatibilty circuit with a constant output current, quasi-
resonant flyback stage. An adaptive dimmer compatibility algorithm controls the dimmer compatibility operation
mode to enable flicker-free operation from 0% to 100% output current with leading-edge, trailing-edge, and digital
dimmers.
The CRD1615A-8W-125V board is optimized to deliver low system cost in a high-efficiency, flicker-free, phase-
dimmable, solid-state lighting (SSL) solution for incandescent lamp replacement applications. The feedback loop is
closed through an integrated digital control system within the IC. Protection algorithms such as output open/short,
current-sense resistor open/short, and overtemperature thermistors protect the system during abnormal conditions.
Details of these features are provided in the CS1615A data sheet.
The CRD1615A-8W-125V board demonstrates the performance of the CS1615A. This reference board has been
designed for an output load of 42xLEDs in series at 58mA (
 125V typical).
This data sheet provides the schematic and PCB layout for the reference design board. The performance graphs
demonstrate the performance of the CS1615A dimmable-controller reference design in terms of Efficiency vs. Line
Voltage, Power Factor vs. Line Voltage, THD vs. Line Voltage, Output Current vs. Line Voltage, and Output Current
vs. Dim Angle.
Extreme caution needs to be exercised while handling this board. This board is to be used by trained professionals
only.