Cirrus Logic CDB150x-01 - Manual (Page 3)

CDB150x-01
DS927DB4 3
1. INTRODUCTION
The CS1501 is a high-performance Variable Frequency Discontinuous Conduction Mode (VF-DCM), ac-
tive Power Factor Correction (PFC) controller, optimized to deliver the lowest system cost in switched
mode power supply (SMPS) applications. The CS1501 uses a digital control algorithm that is optimized
for high efficiency and near-unity power factor over a wide input voltage range (90-265 VAC).
Using an adaptive digital control algorithm, both the ON time and the switching frequency are varied on a
cycle-by-cycle basis over the entire AC line to achieve close-to-unity power factor. The feedback loop is
closed through an integrated digital control system within the IC.
The variation in switching frequency also provides a spread-frequency spectrum, thus minimizing the con-
ducted EMI filtering requirements. Burst mode control minimizes the light-load/standby losses. Protection
features such as overvoltage, overcurrent, overpower, open circuit, overtemperature, and brownout help
protect the device during abnormal transient conditions. Details of these features are provided in the
CS1501 data sheets.
The CDB150x-01 board demonstrates the performance of the CS1501 with input voltage range of 90-265
VAC, typically seen in universal input applications. This board has been designed for 400V V
link
, 90
Watts, full load.
Extreme caution needs to be exercised while handling this board. This board is to be used by trained pro-
fessionals only. Prior to applying AC power to the CDB150x-01 board, the CS1501 needs to be biased
using an external 13 VDC power supply.
This document provides the schematic for the board. It includes oscilloscope screen shots that indicate
operating waveforms. Graphs are also provided that document the performance of the board in terms of
Efficiency vs. Load, Total Harmonic Distortion vs. Load, and Power Factor vs. Load for the CS1501 PFC
controller IC.