Cirrus Logic AN399 - Manual (Page 3)

AN399
3
1. INTRODUCTION
The CS1611 is a 230VAC quasi-resonant flyback mode dimmable LED controller IC. The CS1611 uses a digital con-
trol algorithm that is optimized for high efficiency and > 0.90 power factor over an input voltage range (207VAC -
223VAC). The CS1611 integrates a critical conduction mode (CRM) boost converter that provides power factor cor-
rection and dimmer compatibility with a constant output current, quasi-resonant flyback stage. An adaptive dimmer
compatibility algorithm controls the boost stage and dimmer compatibility operation mode to enable flicker-free op-
eration from 0% to 100% output current with leading-edge, trailing-edge, and digital dimmers.
The CRD1611-11W-30V 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 CS1611 data sheet.
The CRD1611-11W-30V board demonstrates the performance of the CS1611. This reference board has been de-
signed for an output load of 10xLEDs in series at 300mA (
 30V typical).
This data sheet provides the schematic and PCB layout for the reference design board. The performance graphs
demonstrate the performance of the CS1611 dimmable-controller reference design in terms of Efficiency vs. Line
Voltage, Power Factor vs. Line Voltage, THD vs. Line Voltage, and Output Current vs. Line Voltage.
Extreme caution needs to be exercised while handling this board. This board is to be used by trained professionals
only.