Texas Instruments UCC28051DR

Overview

UCC28051DR from Texas Instruments is a transition-mode (boundary-conduction mode) power factor correction (PFC) controller for low-to-medium power boost preregulators, featuring 12.5 V UVLO turn-on threshold, ±750-mA peak gate drive, 2.5 V internal reference, zero-power detect, and OVP protection. It targets IEC 61000-3-2-compliant AC/DC front-ends in AC adapters and two-stage SMPS.

For engineers reviewing the UCC28051DR datasheet, UCC28051DR pinout, UCC28051DR application, or UCC28051DR equivalent, key selection considerations include its narrow 2.8 V UVLO hysteresis, 300 µA g_M amplifier source current for controlled start-up, ZCD-based self-oscillating timing, and compatibility with external MOSFETs in critical conduction mode.

Technical Context

The UCC28051DR implements transition-mode PFC using zero-current detection (ZCD pin) to trigger switch turn-on and current-sense (CS pin) comparison to terminate each switching cycle. Its transconductance error amplifier (g_M = 90 µS typ.) drives a multiplier with VMULTIN (0–2.5 V) and VCOMP (2.5–3.8 V) inputs to generate a line-shaped current command.

It integrates UVLO (12.5 V turn-on / 9.7 V turn-off), overvoltage protection (VREF + 0.18 V threshold), enable/disable via VO_SNS, and zero-power detection (2.3 V COMP threshold) to suppress light-load overvoltage. The DRV output delivers ±750-mA peak current with 25–75 ns rise/fall times into 1 nF load.

Key Specifications

Pinout & Package

UCC28051DR is housed in an 8-pin SOIC (D) package (3.91 mm × 4.90 mm), optimized for surface-mount assembly and thermal performance (R_θJA = 113.6°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transition-mode PFC controller applications.

Compared with UCC28050DR and L6562ADTR, the UCC28051DR uniquely balances system-level control (narrow UVLO for PWM handoff) with robust protection (zero-power detect, 2.68 V OVP), making it optimal for coordinated two-stage AC/DC architectures where bus stability across load range is critical.

Availability

UCC28051DR is available at Aetrix Electronics and suitable for AC adapter front-ends, two-stage desktop SMPS, and industrial motor drive input stages requiring stable component supply, long-term lifecycle support, and full traceability.

Supply support for UCC28051DR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor company delivering analog and embedded processing solutions, with leadership in power management ICs and industrial-grade reliability.

The UCC28051DR belongs to TI's UCC2805x family of transition-mode PFC controllers, designed specifically for cost-effective, high-efficiency boost preregulators in IEC 61000-3-2-compliant consumer and industrial power supplies.

FAQ

What is the UVLO behavior of the UCC28051DR and how does it differ from UCC28050DR?

The UCC28051DR features a 12.5 V turn-on threshold and 9.7 V turn-off threshold, yielding a narrow 2.8 V hysteresis-designed to allow precise activation by a downstream PWM controller after bulk capacitor charging. In contrast, the UCC28050DR uses a 15.8 V turn-on and 9.7 V turn-off (6.3 V hysteresis) for standalone operation. This difference makes UCC28051DR ideal for two-stage power supplies where system-level sequencing is required, and UCC28050DR better for single-stage applications like electronic ballasts. Both share identical pinout and core functionality.

How does the zero-power detect function work in the UCC28051DR?

The UCC28051DR monitors the COMP pin voltage and activates its zero-power detect comparator when COMP falls below 2.3 V nominal. This condition typically occurs under very light or no-load conditions, where the error amplifier output drops due to lack of feedback demand. Upon detection, the controller latches DRV low, halting switching and preventing uncontrolled 385 V bus overvoltage. The feature is enabled by internal circuitry that remains active even during normal regulation, ensuring reliable protection across the full operating temperature range (–40°C to +105°C) without external components.

Can the UCC28051DR drive a 600 V MOSFET directly, and what gate drive capability does it provide?

Yes, the UCC28051DR can directly drive standard 600 V N-channel MOSFETs used in boost PFC stages. Its DRV pin delivers ±750 mA peak source/sink current with 25–75 ns rise time and 10–50 ns fall time into a 1 nF load, enabling fast, low-loss switching. Internal GT1 pull-up/pull-down resistances (5–12 Ω and 2–10 Ω respectively) support robust gate control. An external series gate resistor may be added to damp ringing or limit dV/dt, especially with high-Q gate loops or high-V_DS devices. No external driver stage is required for typical 15–30 A RMS boost applications.

What protection features are integrated into the UCC28051DR?

The UCC28051DR integrates five key protections: (1) Overvoltage protection (OVP) triggers at VO_SNS = VREF + 0.18 V (≈2.68 V) and releases at VREF (2.5 V); (2) Zero-power detect shuts down DRV when COMP < 2.3 V; (3) Enable function disables switching if VO_SNS < 0.23 V (open-feedback fault); (4) Internal CS clamp limits current sense input to ≤1.7 V; and (5) ZCD active clamps prevent negative or excessive positive voltage on the zero-current detect pin. All operate autonomously without external circuitry.

Is the UCC28051DR pin-compatible with other industry-standard PFC controllers?

Yes, the UCC28051DR is pin-compatible with the UCC28050DR, UCC38050, and UCC38051 in the same SOIC-8 (D) and PDIP-8 (P) packages. It also maintains functional and pinout compatibility with legacy industry controllers such as the UC3854 family derivatives, allowing drop-in replacement in many existing designs. However, differences in UVLO thresholds, g_M source current, and OVP hysteresis must be verified in the target application-especially when substituting UCC28051DR for UCC28050DR or vice versa-to ensure correct start-up sequencing and transient response.