Overview
The NCP4390DR2G, produced by onsemi, is an advanced Pulse Frequency Modulated (PFM) controller designed for LLC resonant converters with Synchronous Rectification (SR). This controller is optimized for isolated DC/DC converters, offering best-in-class efficiency. It employs a current mode control technique based on charge control, which simplifies the feedback loop design and allows for true input power limit capability. The NCP4390DR2G features closed-loop soft-start, adaptive synchronous rectification control, and various protection functions, making it a robust solution for high-efficiency power conversion applications.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VDD Pin Supply Voltage to GND | 0 | - | 18 | V |
| Operating Junction Temperature (TJ) | -40 | - | 125 | °C |
| Operating Frequency | 39 kHz | - | 690 kHz | - |
| Soft-Start Capacitor Charge Current (ISS.UP) | 8.2 | 10.5 | 12.8 | μA |
| Over-Current Protection Threshold (VOCP1) | 1.77 | 1.90 | 2.03 | V |
| Junction-to-Ambient Thermal Characteristics (RθJA) | - | - | 115 | °C/W |
Key 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
- 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) with Programmable Shutdown Delay Time
- 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
- Pb-Free, Halogen Free/BFR Free and RoHS Compliant
Applications
- Automotive On Board Charger
- Intelligent 100 W-2 kW+ Off-Line & Industrial Power Supplies
Q & A
- What is the primary function of the NCP4390DR2G?
The NCP4390DR2G is a Pulse Frequency Modulated (PFM) controller for LLC resonant converters with Synchronous Rectification (SR), designed for isolated DC/DC converters.
- What is the operating frequency range of the NCP4390DR2G?
The operating frequency range is from 39 kHz to 690 kHz.
- What protection features does the NCP4390DR2G offer?
The NCP4390DR2G offers Over-Current Protection (OCP), Output Short Protection (OSP), NON Zero-Voltage Switching Prevention (NZS), Power Limit by Compensation Cutback, and Overload Protection (OLP) with programmable shutdown delay time.
- How does the NCP4390DR2G improve light-load efficiency?
The NCP4390DR2G improves light-load efficiency through green functions such as symmetric PWM control at light-load and disabling SR at light-load conditions.
- What is the purpose of the adaptive synchronous rectification control in the NCP4390DR2G?
The adaptive synchronous rectification control with dual edge tracking minimizes body diode conduction time, thus maximizing efficiency.
- What is the significance of the closed-loop soft-start feature in the NCP4390DR2G?
The closed-loop soft-start feature prevents saturation of the error amplifier and allows monotonic rising of the output voltage regardless of load conditions.
- What are the typical applications of the NCP4390DR2G?
The NCP4390DR2G is typically used in automotive on-board chargers and intelligent off-line and industrial power supplies.
- Is the NCP4390DR2G environmentally friendly?
Yes, the NCP4390DR2G is Pb-Free, Halogen Free/BFR Free, and RoHS Compliant.
- What is the operating temperature range of the NCP4390DR2G?
The operating temperature range is from -40°C to +125°C.
- How does the NCP4390DR2G handle current sensing?
The NCP4390DR2G senses instantaneous switch current and the integral of the switch current, typically using a current transformer for sensing primary side current.
