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NCP1612 Datasheet, PDF (1/30 Pages) ON Semiconductor – Enhanced, High-Efficiency Power Factor Controller
NCP1612
Enhanced, High-Efficiency
Power Factor Controller
The NCP1612 is designed to drive PFC boost stages based on an
innovative Current Controlled Frequency Fold−back (CCFF)
method. In this mode, the circuit classically operates in Critical
conduction Mode (CrM) when the inductor current exceeds a
programmable value. When the current is below this preset level, the
NCP1612 linearly decays the frequency down to about 20 kHz when
the current is null. CCFF maximizes the efficiency at both nominal
and light load. In particular, the stand−by losses are reduced to a
minimum.
Like in FCCrM controllers, an internal circuitry allows near−unity
power factor even when the switching frequency is reduced. Housed in
a SO−10 package, the circuit also incorporates the features necessary
for robust and compact PFC stages, with few external components.
General Features
• Near−Unity Power Factor
• Critical Conduction Mode (CrM)
• Current Controlled Frequency Fold−back (CCFF): Low Frequency
Operation is Forced at Low Current Levels
• On−time Modulation to Maintain a Proper Current Shaping in CCFF
Mode
• Skip Mode Near the Line Zero Crossing
• Fast Line / Load Transient Compensation (Dynamic Response
Enhancer)
• Valley Turn On
• High Drive Capability: −500 mA/+800 mA
• VCC Range: from 9.5 V to 35 V
• Low Start−up Consumption
• A Version: Low VCC Start−up Level (10.5 V), B Version: High VCC
Start−up Level (17.0 V)
• Line Range Detection
• pfcOK Signal
• This is a Pb−Free Device
http://onsemi.com
MARKING
DIAGRAM
10
1
SOIC−10
CASE 751BQ
10
1612x
ALYW
G
1
1612x
A
L
Y
W
G
= Specific Device Code
x = A or B
= Assembly Location
= Wafer Lot
= Year
= Work Week
= Pb−Free Package
PIN CONNECTIONS
FOVP/BUV
Feedback
Vcontrol
Vsense
FFcontrol
1
(Top View)
pfcOK
VCC
DRV
GND
CS/ZCD
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 29 of this data sheet.
Safety Features
• Separate Pin for Fast Over−Voltage Protection (FOVP)
and Bulk Under−Voltage Detection (BUV)
• Soft Over−Voltage Protection
• Brown−Out Detection
• Soft−Start for Smooth Start−up Operation (A version)
• Over Current Limitation
• Disable Protection if the Feedback and FOVP/BUV
pins are not connected
• Thermal Shutdown
• Latched Off Capability
• Low Duty−Cycle Operation if the Bypass Diode is
shorted
• Open Ground Pin Fault Monitoring
Typical Applications
• PC Power Supplies
• All Off Line Appliances Requiring Power Factor
Correction
© Semiconductor Components Industries, LLC, 2012
1
June, 2012 − Rev. 1
Publication Order Number:
NCP1612/D