ON Semiconductor NCP1937B1DR2G

Description
The NCP1937 is a combination IC that integrates power factor correction (PFC) and quasi-resonant flyback functionality for compact and efficient switched mode power supplies in adapter applications.

Features

Common General Features
Wide Vcc range (9 V to 30 V) with built-in overvoltage protection
High-voltage startup circuit and active input filter capacitor discharge circuitry for reduced standby power
Integrated high-voltage brown-out detector
Integrated high-voltage switch disconnects PFC feedback resistor divider to reduce standby power
Fault input for severe fault conditions, NTC compatible (latch and auto-recovery options)
0.5 A/0.8 A source/sink gate drivers
Internal temperature shutdown
Power savings mode reduces supply current consumption to 70 μA, enabling very low input power

PFC Controller Features
Critical conduction mode with constant on time control (voltage mode) and maximum frequency clamp
Accurate overvoltage protection
Bi-level line-dependent output voltage
Fast line/load transient compensation
Boost diode short-circuit protection
Feed-forward for improved operation across line and load
Adjustable PFC disable threshold based on output power

QR Flyback Controller Features
Valley switching operation with valley-lockout for noise-free operation
Frequency foldback with minimum frequency clamp for highest performance in standby mode
Minimum frequency clamp eliminates audible noise
Timer-based overload protection (latched or auto-recovery options)
Adjustable overpower protection
Winding and output diode short-circuit protection
4 ms soft-start timer

Applications
Adapters