Overview
The MC33262 is an active power factor correction (PFC) controller designed by onsemi for use in electronic ballast and off-line power converter applications. This integrated circuit is part of the MC34262/MC33262 series, which are specifically tailored to enhance poor power factor loads by maintaining a sinusoidal and in-phase AC line current with the line voltage. The device features an internal startup timer, a one quadrant multiplier for near unity power factor, a zero current detector for critical conduction operation, a transconductance error amplifier, and a quickstart circuit for enhanced startup. It also includes a trimmed internal bandgap reference and a totem pole output suitable for driving a power MOSFET.
Key Specifications
| Characteristic | Symbol | Value | 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 to +10 | V |
| Zero Current Detect Input High State Forward Current | Iin | 50 | mA |
| Power Dissipation and Thermal Characteristics | P | Maximum package power dissipation limits observed | |
| Operating Temperature Range | Ta | −40°C to +105°C | |
| Input Undervoltage Lockout | UVLO | 8 - 13 V with 6.0 V of hysteresis | V |
| Drive Output High State Clamp | VOH(ea) | 5.8 - 6.4 V | V |
| Drive Output Low State Clamp | VOL(ea) | 1.7 - 2.4 V | V |
Key Features
- Internal startup timer for stand-alone applications
- One quadrant multiplier for near unity power factor
- Zero current detector to ensure critical conduction operation
- Transconductance error amplifier with high output impedance
- Quickstart circuit for enhanced startup
- Trimmed internal bandgap reference
- Totem pole output with high state clamp for MOSFET gate protection
- Overvoltage comparator to eliminate runaway output voltage
- Input undervoltage lockout with hysteresis
- Cycle-by-cycle current limiting
- Multiplier output clamp to limit maximum peak switch current
- RS latch for single pulse metering
- Low startup and operating current
Applications
- Active Power Factor Control
- Electronic Ballast
- Off-line Power Converters
Q & A
- What is the primary function of the MC33262?
The MC33262 is an active power factor correction (PFC) controller designed to improve power factor in electronic ballast and off-line power converter applications.
- What are the key components of the MC33262?
The device includes an internal startup timer, one quadrant multiplier, zero current detector, transconductance error amplifier, quickstart circuit, trimmed internal bandgap reference, and a totem pole output.
- What is the operating temperature range of the MC33262?
The operating temperature range is from −40°C to +105°C.
- What protective features does the MC33262 have?
The device includes an overvoltage comparator, input undervoltage lockout with hysteresis, cycle-by-cycle current limiting, multiplier output clamp, and an RS latch for single pulse metering.
- How does the zero current detector work in the MC33262?
The zero current detector initiates the next on-time by setting the RS latch when the inductor current reaches zero, ensuring critical conduction mode operation.
- What type of output does the MC33262 have?
The MC33262 has a totem pole output ideally suited for driving a power MOSFET.
- What is the purpose of the quickstart circuit in the MC33262?
The quickstart circuit enhances the startup process of the device.
- What is the typical transconductance of the error amplifier in the MC33262?
The typical transconductance of the error amplifier is 100 μmhos.
- What are the package options available for the MC33262?
The device is available in dual-in-line (PDIP-8) and surface mount (SOIC-8) plastic packages.
- How does the MC33262 improve power factor?
The MC33262 improves power factor by keeping the AC line current sinusoidal and in phase with the line voltage, significantly reducing harmonic current content.
