Overview
The UC3854AN is an enhanced bipolar Continuous Conduction Mode (CCM) Power Factor Correction (PFC) controller produced by Texas Instruments. This integrated circuit is designed to achieve near-unity power factor in AC-DC power supplies, ensuring that the input line current waveform closely follows the input line voltage. The UC3854AN is particularly suited for high-power applications, such as those requiring compliance with Class D equipment input current harmonics standards per EN61000-3-2, which applies to equipment with rated powers higher than 75 W.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Operating Temperature Range | 0 to 70 | °C |
| Supply Voltage (VCC) | 20 | V |
| VCC Turn-On Threshold | 16 | V |
| VCC Turn-Off Threshold | 10 | V |
| Supply Current (OFF) | 2 | mA |
| Supply Current (ON) | 12 | mA |
| Startup Supply Current | 0.25 | mA |
| Peak Output Sink Current (Gate Drive) | 1 | A |
| Practical Operating Frequency (Max) | 0.2 | MHz |
| Package Type | PDIP (N), SOIC (DW), PLCC (Q) | |
| Pins | 16 (PDIP, SOIC), 20 (PLCC) |
Key Features
- Controls Boost PWM to Near-Unity Power Factor
- Limits Line Current Distortion to < 3%
- World-Wide Operation Without Switches
- Fixed-Frequency Average Current-Mode Control
- High Bandwidth (5 MHz), Low-Offset Current Amplifier
- Integrated Current- and Voltage-Amplifier Output Clamps
- Multiplier Improvements: Linearity, 500 mV AC Offset (Eliminates External Resistor), 0 V to 5 V Multout Common-Mode Range
- VREFGOOD Comparator
- Faster and Improved Accuracy ENABLE Comparator
- UVLO Options (16 V/10 V or 10.5 V/10 V)
- Low Startup Supply Current (300 µA)
Applications
The UC3854AN is generally applicable to the control of AC-DC power supplies that require Active Power Factor Correction (PFC) off universal AC lines. It is particularly useful in applications where compliance with Class D equipment input current harmonics standards per EN61000-3-2 is necessary, such as in equipment with rated powers higher than 75 W. Typical applications include high-power supplies, such as those used in industrial equipment, consumer electronics, and medical devices.
Q & A
- What is the primary function of the UC3854AN?
The UC3854AN is a Power Factor Correction (PFC) controller designed to achieve near-unity power factor in AC-DC power supplies.
- What is the operating temperature range of the UC3854AN?
The operating temperature range is 0°C to 70°C.
- What is the maximum supply voltage for the UC3854AN?
The maximum supply voltage (VCC) is 20 V.
- What is the typical startup supply current for the UC3854AN?
The typical startup supply current is 0.25 mA.
- What type of control method does the UC3854AN use?
The UC3854AN uses fixed-frequency average current-mode control.
- What is the maximum practical operating frequency of the UC3854AN?
The maximum practical operating frequency is 0.2 MHz.
- What are the package options for the UC3854AN?
The UC3854AN is available in 16-pin PDIP (N), 16-pin SOIC (DW), and 20-pin PLCC (Q) packages.
- Does the UC3854AN have integrated current and voltage amplifier output clamps?
- What standards does the UC3854AN help comply with?
The UC3854AN helps comply with Class D equipment input current harmonics standards per EN61000-3-2.
- What is the typical power factor achieved by the UC3854AN?
The UC3854AN can achieve a power factor of near unity, typically around 0.999.
