UCC2818AD Equivalent & Substitute Parts

Part Overview

The UCC2818AD is a Power Factor Correction (PFC) controller IC manufactured by Texas Instruments, designed for average current mode operation across a switching frequency range of 6kHz to 220kHz. This device is packaged in a 16-SOIC surface mount configuration and operates with a supply voltage range of 12V to 17V.

The UCC2818AD has reached Last Time Buy status, indicating that Texas Instruments has discontinued or will discontinue production. This necessitates identification of functionally equivalent substitute components to maintain design continuity and ensure long-term supply chain reliability for applications currently utilizing this controller.

Substiute Parts

UCC2818AD

Texas InstrumentsIn Stock: 2645UCC2818AD Datasheet

Current PartRFQ

UCC28180DR

Texas InstrumentsIn Stock: 25251UCC28180DR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the UCC2818AD is determined by the following critical parameters:

Functional Mode Compatibility: The UCC2818AD operates in average current mode. The UCC28180DR operates in Continuous Conduction (CCM) mode, representing a different control topology. While both are PFC controllers from Texas Instruments, the operational mode difference requires circuit-level evaluation.

Switching Frequency Range: The UCC2818AD supports 6kHz to 220kHz operation. The UCC28180DR supports 18kHz to 250kHz. The overlap range is 18kHz to 220kHz, which defines the compatible operating window for substitution.

Supply Voltage: The UCC2818AD requires 12V to 17V supply. The UCC28180DR operates at 21V supply, representing a higher voltage requirement that may necessitate design modifications.

Package Configuration: The UCC2818AD uses 16-SOIC packaging, while the UCC28180DR uses 8-SOIC packaging. This represents a significant physical and pin-count difference requiring PCB redesign.

Operating Temperature Range: The UCC2818AD operates from -40°C to 85°C. The UCC28180DR extends to -40°C to 125°C, providing broader temperature coverage.

Parameter Comparison

Engineering Selection Recommendations

The UCC28180DR is the manufacturer-recommended substitute for the UCC2818AD. Both devices maintain ROHS3 compliance and unlimited moisture sensitivity rating, ensuring regulatory and environmental compatibility.

The UCC28180DR is currently in Active production status, providing assured long-term availability compared to the Last Time Buy status of the UCC2818AD. This addresses supply chain continuity concerns for new designs or production continuation.

Selection of the UCC28180DR requires verification that the application can accommodate the following differences: Continuous Conduction (CCM) mode operation instead of average current mode, 21V supply voltage requirement instead of 12V to 17V, and 8-SOIC package instead of 16-SOIC package. These differences necessitate circuit redesign and PCB layout modifications.

Frequently Asked Questions (FAQ)

Q: Can the UCC28180DR directly replace the UCC2818AD without circuit modifications?

A: No. The UCC28180DR differs in control mode (CCM vs. average current), supply voltage (21V vs. 12V-17V), and package configuration (8-SOIC vs. 16-SOIC). Circuit redesign is required.

Q: What is the compatible switching frequency range for substitution?

A: The overlapping frequency range between UCC2818AD (6kHz-220kHz) and UCC28180DR (18kHz-250kHz) is 18kHz to 220kHz. Operation outside this range on either device is not guaranteed for substitution compatibility.

Q: Does the UCC28180DR support the same operating temperature range?

A: No. The UCC28180DR extends to -40°C to 125°C, compared to the UCC2818AD range of -40°C to 85°C. The UCC28180DR provides broader temperature coverage.

Q: Are both devices RoHS compliant?

A: Yes. Both the UCC2818AD and UCC28180DR are ROHS3 compliant with unlimited moisture sensitivity rating (MSL 1).

Q: What is the significance of the different startup currents?

A: The UCC2818AD requires 150 µA startup current, while the UCC28180DR requires 75 µA. The lower startup current of the UCC28180DR may reduce inrush current effects during power-on sequencing.

Q: Why is the package size different between these devices?

A: The UCC2818AD uses 16-SOIC packaging with 16 pins, while the UCC28180DR uses 8-SOIC packaging with 8 pins. This reflects the different pin requirements of each control topology and necessitates complete PCB redesign.