Cirrus Logic CRD1631-10W - Manual (Page 3)

CRD1631-10W
DS1005RD2 3
1. INTRODUCTION
The CS1631 is a 230VAC quasi-resonant flyback mode dimmable LED controller IC. The CS1631 uses a digital con-
trol algorithm that is optimized for high efficiency and
 0.90 power factor over a wide input voltage range (207VAC
to 253VAC). The CS1631 integrates a critical conduction mode (CRM) boost converter that provides power factor
correction and dimmer compatibility with a constant output current, quasi-resonant flyback stage. An adaptive dim-
mer compatibility algorithm controls the boost stage and dimmer compatibility operation mode to enable flicker-free
operation to 0% output current with leading-edge, trailing-edge, and digital dimmers. The CS1631's interleaved 2
channel output allows two independent channel constant current regulation and eliminates additional transformers.
Temperature compensated LED current and color control system with NTC maintains constant color temperature
over ambient temperature variation.
The CRD1631-10W 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. The variation in switching frequency and programmable
frequency dithering also provides a spread-frequency spectrum, thus minimizing the conducted EMI filtering require-
ments. 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 CS1631
data sheet.
The CRD1631-10W board demonstrates the performance of the CS1631. This reference board has been designed
for an output load of 4 white LEDs at 483mA (12.96V typical), and 5 red LEDs at 185mA (10V typical) in series 2
channel output configuration at 25
 C.
This document provides the schematic for the board. It includes oscilloscope screen shots that indicate various op-
erating waveforms. Graphs are also provided that document the performance of the board in terms of Efficiency vs.
Line Voltage, Output Current vs. Line Voltage, and Output Current vs. Dim Angle for the CS1631 dimmable LED
controller IC. Extreme caution needs to be exercised while handling this board. This board is to be used by trained
professionals only.
Cirrus Logic, Inc. and its affiliates and subsidiaries generally make no representations or warranties that the
combination of Cirrus Logic’s products with light-emitting diodes (“LEDs”), converter materials, and/or other
components will not infringe any third-party patents, including any patents related to color mixing in LED lighting
applications, such as, for example, U.S. Patent No. 7,213,940 and related patents of Cree, Inc. For more
information, please see Cirrus Logic’s Terms and Conditions of Sale, or contact a Cirrus Logic sales representative.