Overview
The NCP1342AMDCDAD1R2G is a highly integrated quasi-resonant flyback controller produced by onsemi. It is designed for high-performance off-line power converters, particularly in applications such as ac-dc adapters and open-frame power supplies. This controller features an integrated active X2 capacitor discharge capability, which helps in achieving no-load power consumption below 30 mW. The NCP1342 also incorporates proprietary valley-lockout circuitry, ensuring stable valley switching and reducing switching losses by transitioning to frequency foldback mode as the load decreases. Additionally, it enters quiet-skip mode to manage power delivery efficiently while minimizing acoustic noise.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| High Voltage Startup Circuit Input Voltage (VHV) | -0.3 | - | 700 | V |
| Supply Input Voltage (VCC) | -0.3 | - | 30 | V |
| Minimum Operating Voltage (VCC) | 9 | - | - | V |
| VCC Overvoltage Protection Threshold (VCC(OVP)) | 27 | 28 | 29 | V |
| Driver Maximum Voltage (VDRV) | -0.3 | - | VDRV(high) | V |
| Driver Maximum Current (IDRV(SRC)) | - | - | 500 | mA |
| Driver Maximum Current (IDRV(SNK)) | - | - | 800 | mA |
| Operating Junction Temperature (TJ) | -40 | - | 125 | °C |
| Minimum Frequency Clamp (fMIN) | 21.5 | 25 | 27.0 | kHz |
Key Features
- Integrated High-Voltage Startup Circuit with Brownout Detection
- Integrated X2 Capacitor Discharge Capability
- Wide VCC Range from 9 V to 28 V
- 28 V VCC Overvoltage Protection
- Abnormal Overcurrent Fault Protection for Winding Short Circuit or Saturation Detection
- Internal Temperature Shutdown
- Valley Switching Operation with Valley-Lockout for Noise-Free Operation
- Frequency Foldback with 25 kHz Minimum Frequency Clamp for Increased Efficiency at Light Loads
- Rapid Frequency Foldback for Fast Reduction of Switching Frequency at Light Loads
- Skip Mode with Quiet-Skip Technology for Highest Performance During Light Loads
- Minimized Current Consumption for No Load Power Below 30 mW
- Frequency Jittering for Reduced EMI Signature
- Latching or Auto-Recovery Timer-Based Overload Protection
- Adjustable Overpower Protection (OPP)
- Adjustable Maximum Frequency Clamp
- Fault Pin for Severe Fault Conditions, NTC Compatible for OTP
Applications
The NCP1342AMDCDAD1R2G is particularly suited for high-performance off-line power converters, including:
- Ac-dc adapters
- Open-frame power supplies
- Other applications requiring low parts count and cost effectiveness
Q & A
- What is the primary function of the NCP1342AMDCDAD1R2G?
The NCP1342AMDCDAD1R2G is a quasi-resonant flyback controller designed for high-performance off-line power converters.
- What is the no-load power consumption of the NCP1342AMDCDAD1R2G?
The no-load power consumption is below 30 mW.
- What is the operating voltage range of the NCP1342AMDCDAD1R2G?
The operating voltage range is from 9 V to 28 V.
- What protective features does the NCP1342AMDCDAD1R2G include?
The controller includes internal brownout detection, non-dissipative Over Power Protection (OPP), latched overvoltage protection, and NTC-ready overtemperature protection.
- How does the NCP1342AMDCDAD1R2G manage power delivery at light loads?
The controller uses Rapid Frequency Foldback and quiet-skip mode to manage power delivery efficiently while minimizing acoustic noise.
- What is the purpose of the valley-lockout circuitry in the NCP1342AMDCDAD1R2G?
The valley-lockout circuitry ensures stable valley switching and reduces switching losses by transitioning to frequency foldback mode as the load decreases.
- Does the NCP1342AMDCDAD1R2G have an integrated X2 capacitor discharge feature?
Yes, it has an integrated active X2 capacitor discharge capability.
- What is the minimum frequency clamp of the NCP1342AMDCDAD1R2G?
The minimum frequency clamp is 25 kHz.
- Is the NCP1342AMDCDAD1R2G compatible with NTC for overtemperature protection?
Yes, it is NTC compatible for overtemperature protection.
- What is the maximum junction temperature of the NCP1342AMDCDAD1R2G?
The maximum junction temperature is 150°C.
- What are some common applications of the NCP1342AMDCDAD1R2G?
Common applications include ac-dc adapters and open-frame power supplies.
