The NCP13994 is a high performance current mode controller for

half bridge resonant converters. This controller implements

700 V gate drivers, simplifying layout and reducing external

component count. The built−in Brown−Out input function eases

implementation of the controller in all applications. In applications

where a PFC front stage is needed, the NCP13994 features a dedicated

output to drive the PFC controller. This feature together with quiet

skip mode technique further improves light load efficiency of the

whole application. The NCP13994 provides a suite of protection

features allowing safe operation in any application. This includes:

overload protection, over−current protection to prevent hard switching

cycles, brown−out detection, line brown−out, line OVP, X2 cap

discharge, open optocoupler detection, automatic dead−time adjust,

over−voltage (OVP) and over−temperature (OTP) protections.

Features

• Up to 700 V Operating Range for High Side Driver

• Up to 700 V Operating Range for HV Startup Current Source

• Line Brown−out and OVP Protections

• X2 Cap Discharge Function

• Clamped Output Drivers

• Up to 30 V Supply

• High−Frequency Operation from 20 kHz up to 750 kHz

• Current Mode Control Scheme

• Automatic Dead−time with Maximum Dead−time Clamp

• Enhanced Startup Sequence for Fast Resonant Tank Stabilization

• Light Load Operation Mode for Improved Efficiency

• Quiet Skip Operation Mode for Minimize Transformer Acoustic

Noise

• Off−mode Operation for Extremely Low No−load Consumption

• Latched or Auto−recovery Overload Protection

• Latched or Auto−recovery Output Short Circuit Protection with

Current Reduction

• Latched Input for Severe Fault Conditions, e.g. OVP or OTP

• Out of Resonance Switching Protection

• Open Feedback Loop Protection

• Precise Brown−out Protection

• PFC Stage Operation Control According to Load Conditions

• Startup Current Source with Extremely Low Leakage Current

• Dynamic Self−Supply (DSS) Operation in Off−mode or Fault Modes

Features (continued)

• Pin to Adjacent Pin / Open Pin Fail Safe

• This is a Pb−Free Device

Typical Applications

• Adapters and Offline Battery Chargers

• Flat Panel Display Power Converters

• Computing Power Supplies

• Industrial and Medical Power Sources