Overview
The MC33262, specifically the SC33262DR2G, is an active power factor controller designed by onsemi. This integrated circuit is primarily used as a preconverter in electronic ballast and off-line power converter applications. It features a range of advanced functionalities to ensure high performance and reliability in power factor correction (PFC) systems.
The device includes an internal startup timer, a one-quadrant multiplier for near unity power factor, a zero current detector for critical conduction operation, and a transconductance error amplifier. Additional protective features such as overvoltage comparator, input undervoltage lockout, cycle-by-cycle current limiting, and MOSFET gate protection enhance its robustness.
Key Specifications
Characteristic | Symbol | Min | Typ | Max | Unit |
---|---|---|---|---|---|
Total Power Supply and Zener Current | ICC + IZ | - | - | 30 | mA |
Output Current, Source or Sink | IO | - | - | 500 | mA |
Current Sense, Multiplier, and Voltage Feedback Inputs | Vin | -1.0 | - | +10 | V |
Operating Junction Temperature | TJ | - | - | +150 | °C |
Operating Ambient Temperature | TA | -40 | - | +105 | °C |
Transconductance | gm | 80 | 100 | 130 | μmho |
Output Voltage Swing High State | VOH(ea) | 5.8 | 6.4 | - | V |
Output Voltage Swing Low State | VOL(ea) | 1.7 | 2.4 | - | V |
Key Features
- Internal Startup Timer: For stand-alone applications.
- One Quadrant Multiplier: For near unity power factor.
- Zero Current Detector: Ensures critical conduction operation.
- Transconductance Error Amplifier: High output impedance with controlled voltage-to-current gain.
- Quickstart Circuit: Optimizes converter startup by precharging the compensation capacitor.
- Trimmed Internal Bandgap Reference: 2% accuracy.
- Totem Pole Output with High State Clamp: Ideal for driving power MOSFETs.
- Undervoltage Lockout with Hysteresis: Prevents operation below a certain voltage threshold.
- Overvoltage Comparator: Eliminates runaway output voltage due to load removal.
- Low Startup and Operating Current: Efficient power management.
- Pb-Free and Halide-Free: Environmentally friendly packaging.
Applications
The MC33262 is widely used in various power conversion applications, including:
- Electronic Ballast: For lighting systems requiring high power factor correction.
- Off-Line Power Converters: In applications such as switch-mode power supplies and DC-DC converters.
- Power Factor Correction (PFC) Preconverters: To improve the power factor and reduce line current distortion in high-power systems.
- High-Frequency Switching Applications: Where critical conduction mode operation is beneficial.
Q & A
- What is the primary function of the MC33262?
The MC33262 is an active power factor controller designed for use as a preconverter in electronic ballast and off-line power converter applications.
- What are the key features of the MC33262?
Key features include an internal startup timer, one-quadrant multiplier, zero current detector, transconductance error amplifier, quickstart circuit, and protective features like overvoltage comparator and undervoltage lockout.
- What is the operating temperature range of the MC33262?
The operating ambient temperature range is from -40°C to +105°C.
- What is the maximum output current of the MC33262?
The maximum output current is 500 mA.
- How does the zero current detector work in the MC33262?
The zero current detector initiates the next on-time by setting the RS latch at the instant the inductor current reaches zero, ensuring critical conduction mode operation.
- What is the purpose of the quickstart circuit in the MC33262?
The quickstart circuit optimizes converter startup by precharging the compensation capacitor to a level slightly below the multiplier threshold, allowing immediate drive output switching and bootstrap operation.
- Is the MC33262 Pb-Free and Halide-Free?
Yes, the MC33262 is Pb-Free and Halide-Free, making it an environmentally friendly option.
- What are the typical applications of the MC33262?
Typical applications include electronic ballast, off-line power converters, PFC preconverters, and high-frequency switching applications.
- What is the maximum power dissipation of the MC33262 at 70°C?
The maximum power dissipation varies by package type but is typically around 800 mW for the PDIP package and 450 mW for the SOIC package.
- How does the overvoltage comparator protect the MC33262?
The overvoltage comparator eliminates runaway output voltage due to load removal, preventing potential damage to the device.