The NCV4390 is an advanced Pulse Frequency Modulated (PFM)

controller for LLC resonant converters with Synchronous

Rectification (SR) that offers best in class efficiency for isolated

DC/DC converters. It employs a current mode control technique based

on a charge control, where the triangular waveform from the oscillator

is combined with the integrated switch current information to

determine the switching frequency. This provides a better

control?to?output transfer function of the power stage simplifying the

feedback loop design while allowing true input power limit capability.

Closed?loop soft?start prevents saturation of the error amplifier and

allows monotonic rising of the output voltage regardless of load

condition. A dual edge tracking adaptive dead time control minimizes

the body diode conduction time thus maximizing efficiency.

特性 Features

? Secondary Side PFM Controller for LLC Resonant Converter with

Synchronous Rectifier Control

? Charge Current Control for Better Transient Response and Easy

Feedback Loop Design

? Adaptive Synchronous Rectification Control with Dual Edge

Tracking

? Closed Loop Soft?Start for Monotonic Rising Output

? Wide Operating Frequency (39 kHz ~ 690 kHz)

? Green Functions to Improve Light?Load Efficiency

? Symmetric PWM Control at Light?Load to Limit the Switching

Frequency while Reducing Switching Losses

? Disabling SR at Light?Load Condition

? Protection Functions with Auto?Restart

? Over?Current Protection (OCP)

? Output Short Protection (OSP)

? NON Zero?Voltage Switching Prevention (NZS) by

Compensation Cutback (Frequency Shift)

? Power Limit by Compensation Cutback (Frequency Shift)

? Overload Protection (OLP)

? Programmable Dead Times for Primary Side Switches and Secondary

Side Synchronous Rectifiers

? VDD Under?Voltage Lockout (UVLO)

? Wide Operating Temperature Range ?40°C to +125°C

? Automotive Qualified to AEC?Q100 Grade 1

? This Device is Pb?Free, Halogen Free/BFR Free and is RoHS Compliant

Applications

? Automotive On Board Charger

? EV High Voltage DC/DC Converters