Cirrus Logic AN400 - Manual (Page 3)

AN400
3
1. INTRODUCTION
The CS1615 is a 120VAC quasi-resonant buck-boost mode dimmable LED controller IC. The CS1615 uses a digital
control algorithm that is optimized for high efficiency and > 0.90 power factor over an input voltage range (108VAC
-132VAC). The CS1615 integrates a dimmer compatibilty circuit with a constant output current, quasi-resonant fly-
back 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 CRD1615-11W-36V 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 CS1615 data sheet.
The CRD1615-11W-36V board demonstrates the performance of the CS1615. This reference board has been de-
signed for an output load of 12xLEDs in series at 250mA (
 36V typical).
This data sheet provides the schematic and PCB layout for the reference design board. The performance graphs
demonstrate the performance of the CS1615 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.