Overview
The NCP4308DDR2G, produced by onsemi, is a synchronous rectifier controller designed for switch mode power supplies. This controller is optimized for high efficiency in various topologies, including flyback, quasi-resonant flyback, and LLC (Inductor-Inductor-Capacitor) configurations. It features a robust architecture that ensures reliable and noiseless operation of the synchronous rectification system. The NCP4308DDR2G is versatile and can operate either as a standalone IC or as a companion IC to a primary side controller, enhancing the efficiency of synchronous rectification in power supplies.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Supply Voltage (VCC) | −0.3 to 37.0 | V |
| Operating Frequency | Up to 1 MHz | |
| Driver Output Voltage (VDRV) | −0.3 to 17.0 | V |
| Current Sense Input Voltage (VCS) | −4 to 150 | V |
| Peak Source Current (IDRV_SOURCE) | 4 A | A |
| Peak Sink Current (IDRV_SINK) | 8 A | A |
| Minimum On-Time (tON_MIN) | 25 to 75 ns (DFN8, WDFN8) | ns |
| Minimum Off-Time (tOFF_MIN) | 160 to 290 ns (DFN8, WDFN8) | ns |
| Maximum Junction Temperature (TJMAX) | 150 | °C |
| Package Types | SOIC-8, DFN-8 (4x4), WDFN8 (2x2) |
Key Features
- Self-Contained Control: Supports continuous conduction mode (CCM), discontinuous conduction mode (DCM), and quasi-resonant (QR) for flyback and LLC applications.
- Precise True Secondary Zero Current Detection: Ensures accurate turn-off threshold.
- Rugged Current Sense Pin: Up to 150 V.
- Adjustable Minimum On-Time and Off-Time: With ringing detection for flexibility in driving various MOSFET package types and PCB layouts.
- Improved Robust Self Synchronization Capability: Ensures reliable and noiseless operation.
- GaN Transistor Driving Capability: Suitable for directly driving GaN devices.
- Low Startup Current Consumption: Efficient startup operation.
- High Accuracy Driver and 5 V Gate Clamp: Optimized for high efficiency operation.
- Adjustable Maximum On-Time for CCM Controlling of Primary QR Controller: Enhances performance in quasi-resonant applications.
Applications
- Notebook Adapters
- High Power Density AC/DC Power Supplies (e.g., cell phone chargers)
- LCD TVs
- All SMPS with High Efficiency Requirements
Q & A
- What is the primary function of the NCP4308DDR2G?
The NCP4308DDR2G is a synchronous rectifier controller designed for switch mode power supplies to enhance efficiency in flyback, quasi-resonant flyback, and LLC topologies.
- What are the key package types available for the NCP4308DDR2G?
The NCP4308DDR2G is available in SOIC-8, DFN-8 (4x4), and WDFN8 (2x2) packages.
- What is the operating voltage range of the NCP4308DDR2G?
The operating voltage range is from 4 V to 35 V.
- What is the maximum operating frequency of the NCP4308DDR2G?
The maximum operating frequency is up to 1 MHz.
- Does the NCP4308DDR2G support GaN transistor driving?
- What are the typical applications of the NCP4308DDR2G?
Typical applications include notebook adapters, high power density AC/DC power supplies, LCD TVs, and all SMPS with high efficiency requirements.
- How does the NCP4308DDR2G handle turn-off current threshold?
The NCP4308DDR2G offers a turn-off threshold of 0 mV, significantly reducing the turn-off current threshold and improving efficiency compared to other SR controllers.
- What is the purpose of the adjustable minimum on-time and off-time blanking periods?
These periods can be adjusted independently of IC VCC using external resistors to overcome false triggering issues after turn-on and turn-off events.
- How does the NCP4308DDR2G ensure reliable operation during startup?
The controller features low startup current consumption and uses the pulsing voltage at the SR transistor gate to provide enough supply to activate the internal driver sink transistor, eliminating the risk of premature SR transistor turn-on.
- What is the maximum junction temperature of the NCP4308DDR2G?
The maximum junction temperature is 150°C.
