Product Overview

Product Overview
NCP1631: Power Factor Controller, 2-Phase, Interleaved
For complete documentation, see the data sheet
Product Description
The NCP1631 is a controller for use in 2-phase interleaved power factor correction pre-converters. Interleaving consists of
paralleling two small stages in lieu of a single big stage. This approach has several merits like ease of implementation, ability to use
smaller components, and better distribution of heating. These attributes make the interleaved PFC topology attractive to slim form
factor applications such as flat panel TVs and ultra-slim notebook adapters. Interleaving can also extend the power range of Critical
Conduction Mode, which is an efficient and cost-effective (no need for low trr diodes) operating mode. The NCP1631 operates in
Frequency Clamped Critical Conduction mode (FcCrM). The circuit utilizes frequency foldback to linearly decay the clamping
frequency as a function of power. As a result, the NCP1631 provides optimized efficiency across the load range. In addition, the
NCP1631 drivers exhibit a 180 phase shift for a significantly reduced current ripple, which lowers EMI and reduces the rms current in
the bulk capacitor. The NCP1631 incorporates all the features necessary for building robust and compact interleaved PFC stages,
with a minimum of external components. Available in SOIC-16 package.
Features
Benefits
• 180° out of phase operation
• Frequency foldback at low power
• Integrated overcurrent protection, overvoltage protection,
UVLO, and brown-out protection
• Frequency clamped critical conduction mode (FcCrM)
operation
Applications
• Low EMI and reduces RMS current in the bulk capacitor
• Improved light load efficiency
• Increased robustness with few external components
• Optimized efficiency over the load range
End Products
• Flat panel TVs
• SMPS
• Offline appliances requiring power factor correction
• LCD TV
• Computer power supplies
• Servers
Part Electrical Specifications
Product
Compliance
Status
PFC
Mode
Freque Control Topolo
ncy
Mode
gy
Operati
on
fSW Typ VCC
(kHz)
Max
(V)
Drive
Cap.
(mA)
UVLO
(V)
Latch
UVP
Inhibiti
on
Packag
e Type
NCP1631DR2G
Pb-free
Active
CRM
Variabl
e
Up to
500
500 /
500
9.5 12
Yes
Yes
YES
SOIC16
Halide free
Voltag Stepe Mode Up
20
Application Diagram
For more information please contact your local sales support at www.onsemi.com
Created on: 6/30/2016