Onsemi NCP1602

Description

The 6−pin PFC controller NCP1602 is designed to drive PFC boost stages. It is based on an innovative Valley Synchronized FrequencyFold−back (VSFF) method. In this mode, the circuit classically operates in Critical conduction Mode (CrM) when Vcontrol voltage exceeds a programmable value Vctrl,FF. When Vcontrol is below this preset level Vctrl,FF, the NCP1602 (versions [B] and [D]) linearly decays the frequency down to about 30 kHz until Vcontrol reaches the SKIP mode threshold. VSFF maximizes the efficiency at both nominal and light load. In particular, the stand−by losses are reducedto a minimum. Like in FCCrM controllers, internal circuitry allows near−unity power factor even when the switching frequency is reduced. Housed in a TSOP6 package, the circuit also incorporates thefeatures necessary for robust and compact PFC stages, with few external components.

Features

• Near−Unity Power Factor
• Two−Level Boost Follower Line Level Dependent (disabled by default)
• Critical Conduction Mode (CrM)
• Valley Synchronized Frequency Fold−back (VSFF): Low FrequencyOperation is Forced at Low Current Levels (9 pre−programmed settings).
• Works With or Without a Transformer w/ ZCD Winding (simple inductor)
• On−time Modulation to Maintain a Proper Current Shaping in VSFF Mode
• Skip Mode at Very Low Load Current (versions[ B] and [D])
• 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 30 V
• Low Start−up Consumption for:[C] & [D] Versions: Low Vcc Start−up level (10.5 V)[A] & [B] Versions: High Vcc Start−up level (17.0 V)
• Line Range Detection for Reduced
• This is a Pb−Free Device

Safety Features

• Thermal Shutdown
• Non−latching, Over−Voltage Protection
• Second Over−Voltage Protection
• Brown−Out Detection
• Soft−Start for Smooth Start−up Operation ([C] &[D] Versions)
• Over Current Limitation
• Disable Protection if the Feedback Pin is Not Connected
• Low Duty−Cycle Operation if the Bypass Diode isShorted
• Open Ground Pin Fault Monitoring

Typical applications

• Lighting Ballasts (LED, Fluorescent)
• All Off Line Appliances Requiring Power Factor Correction
• PC Power Supplies
• Flat TV

More information

• Datasheet
• IC product information