Overview
The NCP1612A1DR2G is an enhanced, high-efficiency power factor controller (PFC) produced by onsemi. This integrated circuit is designed to drive PFC boost stages using the innovative Current Controlled Frequency Fold-back (CCFF) method, which maximizes efficiency at both nominal and light load conditions. The device operates in Critical Conduction Mode (CrM) and incorporates features such as near-unity power factor, on-time modulation, and skip mode near the line zero crossing. It is housed in a SOIC-10 package, making it suitable for robust and compact PFC stages with minimal external components.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| VCC Range | 9.5 to 35 | V |
| FOVP Pin Range | -0.3 to 10 | V |
| Feedback Pin Range | -0.3 to 10 | V |
| DRV Pin Voltage/Current | -0.3 to VDRV / -500 to +800 | V / mA |
| pfcOK Pin Range | -0.3 to VCC | V |
| Maximum Power Dissipation @ TA = 70°C | 550 | mW |
| Thermal Resistance Junction-to-Air | 145 | °C/W |
| Operating Junction Temperature Range | -40 to +125 | °C |
| Typical UVLO Hysteresis | 1.5 V | V |
| Maximum Dead-time | 48.5 µs | µs |
Key Features
- Near-unity Power Factor
- Critical Conduction Mode (CrM)
- Current Controlled Frequency Fold-back (CCFF): Low Frequency Operation at Low Current Levels
- On-time Modulation to Maintain Proper Current Shaping in CCFF Mode
- Skip Mode Near the Line Zero Crossing
- Fast Line/Load Transient Compensation (Dynamic Response Enhancer)
- Valley Turn On
- High Drive Capability: -500 mA/+800 mA
- Low Start-up Consumption
- Six Versions: NCP1612A, B, A1, A2, A3, and B2
- Line Range Detection
- pfcOK Signal
- Safety Features:
- Separate Pin for Fast Over-voltage Protection (FOVP)
- Soft Over-voltage Protection
- Brown-out Detection
- Soft-start for Smooth Start-up Operation (A, A1, A2, and A3 Versions)
- Over Current Limitation
- Disable Protection if Feedback is Not Connected
- Thermal Shutdown
- Latched Off Capability
- Low Duty-cycle Operation if Bypass Diode is Shorted
- Open Ground Pin Fault Monitoring
- Saturated Inductor Protection
Applications
- PC Power Supplies
- All Off-line Appliances Requiring Power Factor Correction
Q & A
- What is the primary function of the NCP1612A1DR2G?
The NCP1612A1DR2G is a high-efficiency power factor controller designed to drive PFC boost stages.
- What is the operating voltage range of the VCC pin?
The VCC pin operates within a range of 9.5 V to 35 V.
- What is the Current Controlled Frequency Fold-back (CCFF) method?
The CCFF method linearly decays the frequency down to about 20 kHz when the inductor current is null, maximizing efficiency at both nominal and light load conditions.
- What safety features are included in the NCP1612A1DR2G?
The device includes features such as fast over-voltage protection, soft over-voltage protection, brown-out detection, soft-start, over current limitation, thermal shutdown, and more.
- What is the purpose of the pfcOK signal?
The pfcOK signal indicates when the PFC output has reached its nominal level and is also grounded if the NCP1612 detects a fault.
- What are the typical applications of the NCP1612A1DR2G?
Typical applications include PC power supplies and all off-line appliances requiring power factor correction.
- What is the package type of the NCP1612A1DR2G?
The device is housed in a SOIC-10 package.
- What is the maximum power dissipation at TA = 70°C?
The maximum power dissipation is 550 mW.
- What is the thermal resistance junction-to-air?
The thermal resistance junction-to-air is 145 °C/W.
- What are the different versions of the NCP1612 available?
The available versions are NCP1612A, B, A1, A2, A3, and B2.
