Overview
The NCP1342AMAACD1R2G, produced by onsemi, is a highly integrated quasi-resonant flyback controller designed for high-performance off-line power converters. This controller is particularly suited for applications requiring low parts count and cost effectiveness, such as AC-DC adapters, open-frame power supplies, and other high-density power conversion systems. It features an integrated active X2 capacitor discharge capability, which enables no-load power consumption below 30 mW, aligning with stringent energy efficiency standards.
Key Specifications
| Characteristics | Conditions | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|---|
| Supply Voltage | VCC increasing | VCC(on) | 10.5 | 11.5 | 12.5 | V |
| Startup Threshold | VCC increasing | VCC(start) | 16.5 | 18.5 | 20.5 | V |
| Minimum Operating Voltage | VCC decreasing | VCC(min) | 8.5 | 9.5 | 10.5 | V |
| Operating Hysteresis | VCC decreasing | VCC(hys) | 1.5 | 2.5 | 3.5 | V |
| Internal Latch / Logic Reset Level | VCC decreasing | VCC(reset) | 4.5 | 5.5 | 6.5 | V |
Key Features
- Minimum Peak Current Modulation for Rapid Frequency Foldback (RFF): Reduces switching frequency quickly to improve efficiency over the load range.
- QR Frequency Jittering: Enhances efficiency and reduces EMI.
- Quiet-Skip Technology: Manages power delivery while minimizing acoustic noise at light loads.
- Integrated HV Startup with Brownout Protection: Ensures low standby power consumption and protects against low input voltage.
- Valley Switching Operation with Valley Lockout: Ensures stable valley switching down to the 6th valley.
- Integrated X2 Capacitor Discharge Capability: Automatically discharges X2 capacitors, eliminating the need for discharge resistors and reducing power consumption.
- NTC Compatible Fault Pin: Supports overtemperature protection through a dedicated pin.
- High Drive Capability: -500 mA / +800 mA for robust MOSFET control.
- Latch input for OVP and OTP implementation: Allows for latched overvoltage and overtemperature protection.
Applications
- Medium or High Power AC-DC Adapters: Suitable for high-density power conversion.
- Ultra High Density AC-DC Adapters: Ideal for compact power supply designs.
- USB PD Compliant Adapters: Supports USB Power Delivery applications.
- Notebook Adapters: Used in laptop power supplies.
- Flat TV SMPS: Suitable for flat-screen TV power supplies.
- Computer Power Supplies: Used in desktop and server power supplies.
- Phone and Tablet Adapters: Ideal for mobile device chargers.
Q & A
- What is the NCP1342AMAACD1R2G used for?
The NCP1342AMAACD1R2G is used for designing high-performance off-line power converters, particularly in applications such as AC-DC adapters, open-frame power supplies, and other high-density power conversion systems.
- What is the no-load power consumption of the NCP1342?
The NCP1342 can enable no-load power consumption below 30 mW due to its integrated active X2 capacitor discharge feature.
- What protective features does the NCP1342 implement?
The NCP1342 implements several protective features including internal brownout detection, non-dissipative Over Power Protection (OPP), latched overvoltage and NTC-ready overtemperature protection, and line removal detection.
- How does the NCP1342 manage light load performance?
The NCP1342 incorporates Minimum Peak Current Modulation (MPCM) for rapid frequency foldback and quiet-skip mode to manage power delivery while minimizing acoustic noise at light loads.
- What is the significance of the integrated X2 capacitor discharge capability?
The integrated X2 capacitor discharge capability automatically discharges X2 capacitors, eliminating the need for discharge resistors and reducing power consumption.
- What is the high drive capability of the NCP1342?
The NCP1342 has a high drive capability of -500 mA / +800 mA for robust MOSFET control.
- Is the NCP1342 compatible with USB Power Delivery (PD) applications?
Yes, the NCP1342 is suitable for USB PD compliant adapters.
- What are some common applications of the NCP1342?
Common applications include medium or high power AC-DC adapters, ultra high density AC-DC adapters, notebook adapters, flat TV SMPS, computer power supplies, and phone and tablet adapters.
- How does the NCP1342 ensure converter ruggedness?
The NCP1342 ensures converter ruggedness through features such as internal brownout detection, non-dissipative OPP, latched overvoltage and overtemperature protection, and line removal detection.
- What is the significance of the valley-lockout circuitry in the NCP1342?
The valley-lockout circuitry ensures stable valley switching down to the 6th valley and transitions to frequency foldback mode to reduce switching losses.
