To learn more about onsemi™, please visit our website at

www.onsemi.com

ON Semiconductor

Is Now

onsemi and and other names, marks, and brands are registered and/or common law trademarks of Semiconductor Components Industries, LLC dba “onsemi” or its affiliates and/or

subsidiaries in the United States and/or other countries. onsemi owns the rights to a number of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of onsemi

product/patent coverage may be accessed at www.onsemi.com/site/pdf/Patent-Marking.pdf. onsemi reserves the right to make changes at any time to any products or information herein, without

notice. The information herein is provided “as-is” and onsemi makes no warranty, representation or guarantee regarding the accuracy of the information, product features, availability, functionality,

or suitability of its products for any particular purpose, nor does onsemi assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all

liability, including without limitation special, consequential or incidental damages. Buyer is responsible for its products and applications using onsemi products, including compliance with all laws,

regulations and safety requirements or standards, regardless of any support or applications information provided by ons emi. “Typical” parameters which may be provided in onsemi data sheets and/

or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application

by customer’s technical experts. onsemi does not convey any license under any of its intellectual property rights nor the rights of others. onsemi products are not designed, intended, or authorized

for use as a critical component in life support systems or any FDA Class 3 medical devices or medical devices with a same or similar classification in a foreign jurisdiction or any devices intended for

implantation in the human body. Should Buyer purchase or use onsemi products for any such unintended or unauthorized application, Buyer shall indemnify and hold onsemi and its officers, employees,

subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death

associated with such unintended or unauthorized use, even if such claim alleges that onsemi was negligent regarding the design or manufacture of the part. onsemi is an Equal Opportunity/Affirmative

Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner. Other names and brands may be claimed as the property of others.

October, 2009 − Rev. 2

1 Publication Order Number:

AND8324/D

300 W, Wide Mains, PFC

Stage Driven by the

NCP1654

Prepared by: Patrick Wang

ON Semiconductor

Introduction

The NCP1654 is a Power Factor Controller to efficiently

drive Continuous Conduction Mode (CCM) step−up

pre−converters. As shown by the ON Semiconductor

application note AND8322, “Four Key Steps to Design a

Continuous Conduction Mode PFC Stage Using the

NCP1654”, which details the four key steps to design a

NCP1654 driven PFC stage, this circuit represents a major

leap towards compactness and ease of implementation.

Housed in a SO−8 package, the circuit minimizes the

external components count without sacrificing performance

and flexibility. In particular, the NCP1654 integrates all the

key protections to build robust PFC stages like an effective

input power runaway clamping circuitry.

When needed or wished, the NCP1654 also allows

operation in Follower Boost mode

(1)

to drastically lower the

pre−converter size and cost, in a straight−forward manner.

For more information on this device, please refer to the

ON Semiconductor data sheet NCP1654/D.

The board illustrates the circuit capability to effectively

drive a high power, universal line application. More

specifically, it is designed to meet the following

specifications:

• Maximum output power: 300 W

• Input voltage range: from 85 V

RMS

to 265 V

RMS

• Regulation output voltage: 390 V

• Switching frequency: 65 kHz

This application was tested using an active load. As in

many applications, the PFC controller is fed by an output of

the downstream converter, there is generally no need for an

auto−supply circuitry. Hence, in our demo board, the

NCP1654 V

is to be supplied by a 15 V external power

supply.

The external voltage source that is to be applied to the

NCP1654 V

, should exceed 10.5 V typical, to allow the

circuits start up. After start up, the V

operating range is

from 9 V to 20 V.

The voltage applied to the NCP1654 V

must NOT

exceed 20 V.

The NCP1654 is a continuous conduction mode and fixed

frequency controller (65 kHz). The coil (650 uH) is selected

to limit the peak to peak current ripple in the range of 36 %

at the sinusoid top, in full load and low line conditions.

Again, for details on how the application is designed, please

refer to the ON Semiconductor application note AND8322,

”Four Key Steps to Design a Continuous Conduction Mode

PFC Stage Using the NCP1654”.

As detailed in the document, the board yields very nice

Power Factor ratios and effectively limits the Total

Harmonic Distortion (THD).

http://onsemi.com