UCC3818N PFC Power Factor Correction Controller IC DIP16

Description

Overview

The UCC3818N is a high-performance PFC controller from Texas Instruments designed for active power factor-corrected preregulators . It achieves near-unity power factor by shaping the AC input line current waveform to match the AC input line voltage waveform using average current mode control . The device is fabricated on TI’s advanced BiCMOS process, which provides lower power dissipation and improved performance compared to bipolar alternatives .

This is the through-hole PDIP-16 version, ideal for prototyping, hobbyist projects, and applications where manual assembly or socket mounting is preferred.

Electrical Specifications

Switching & Control Specifications

Protection & Key Features

Package & Mechanical Specifications

Environmental & Thermal Ratings

Applications

• Active Power Factor Correction in switch-mode power supplies (SMPS)

• AC-DC Converters requiring near-unity power factor (meets IEC61000-3-2 standards) 

• Boost Preregulators for offline power supplies 

• Systems requiring low input current harmonic distortion

Important Design Notes

1. External MOSFET Required: The UCC3818N is a controller IC, not a standalone PFC stage. It requires external power switching components (MOSFET, inductor, diodes) .

2. VCC Supply: The device needs a clean 12V-17V supply. Below 10.5V, the UVLO circuit will keep the device disabled .

3. Frequency Setting: The switching frequency is programmable via external resistor and capacitor connected to the OSC pin.

4. Current Sensing: A current sense resistor is required in the boost converter’s return path for the current amplifier input.

5. Not Recommended for New Designs (NRND)? While TI still lists the device as ACTIVE , the newer UCC2818 (industrial temperature range -40°C to 85°C) or UCC3818D (SOIC-16 surface mount) may be preferred for new designs.

Pin Configuration (PDIP-16)

*Standard 16-pin DIP configuration with 0.3″ body width, 0.1″ pin spacing*

The key pins include:

• VCC (pin 11) – Power supply input (12V-17V)

• GND (pin 12) – Ground return

• OUT (pin 9) – Gate driver output to external MOSFET

• VSENSE – Voltage feedback for output regulation

• MOUT – Current amplifier output

• IAC – AC line current sense input

• OSC – Oscillator timing (frequency set by R and C)