NCP1611 Datasheet, PDF (1/28 Pages) ON Semiconductor – Enhanced, High-Efficiency Power Factor Controller

NCP1611
Enhanced, High-Efficiency
Power Factor Controller
The NCP1611 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
NCP1611 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, internal circuitry allows near−unity
power factor even when the switching frequency is reduced. Housed in
a SO−8 package, the circuit also incorporates the features necessary
for robust and compact PFC stages, with few external components.
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
• V_CC Range: from 9.5 V to 35 V
• Low Start−up Consumption
• A Version: Low V_CC Start−up Level (10.5 V), B Version: High V_CC
Start−up level (17.0 V)
• Line Range Detection
• This is a Pb−Free Device
http://onsemi.com
MARKING
DIAGRAM
8
1
SOIC−8
CASE 751
SUFFIX D
8
NCP1611x
ALYW
G
1
NCP1611x = Specific Device Code
x = A or B
A
= Assembly Location
L
= Wafer Lot
Y
= Year
W
= Work Week
G
= Pb−Free Package
PIN CONNECTIONS
V_control
V_sense
FF_control
CS/ZCD
1
(Top View)
Feedback
V_CC
DRV
GND
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 27 of this data sheet.
Safety Features
• Non−latching, Over−Voltage Protection
• Brown−Out Detection
• Soft−Start for Smooth Start−up Operation (A version)
• Over Current Limitation
• Disable Protection if the Feedback Pin is Not Connected
• Thermal Shutdown
• 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, 2011
1
December, 2011 − Rev. 1
Publication Order Number:
NCP1611/D