UCC28742

ACTIVE

High-Efficiency Flyback controller With Optocoupler Feedback

Top

Product details

Parameters

Control method Secondary-side regulation Duty cycle (Max) (%) 99 Frequency (Max) (kHz) 105 UVLO thresholds on/off (V) 22/7.7 Features SSR, DCM Operating temperature range (C) -40 to 125 Rating Catalog open-in-new Find other Flyback controllers

Package | Pins | Size

SOT-23 (DBV) 6 5 mm² 2.9 x 1.6 open-in-new Find other Flyback controllers

Features

  • Opto-Coupled Feedback Enables up to 1% Regulation
  • Accurate Current Limit with Overload Timeout Protection and Delayed Hiccup Response
  • Resonant-Ring Valley-Switching Operation for Highest Overall Efficiency
  • 80-kHz Maximum Switching Frequency
  • Frequency Dithering to Ease EMI Compliance
  • Clamped Gate-Drive Output for MOSFET
  • Ultra-Low Start-Up Current and Large VDD Hysteresis
    • High Value Start-Up Resistor
    • Low Bias Capacitance
  • Fault Protections
    • Input Low Line
    • Output Over-Voltage
    • Over-Current
    • Short-Circuit
  • SOT23-6 Package
  • Create a Custom Design Using the UCC28742 with the WEBENCH® Power Designer

All trademarks are the property of their respective owners.

open-in-new Find other Flyback controllers

Description

The UCC28742 off-line flyback controller is a highly integrated, 6-pin secondary-side regulated PWM controller for efficient AC-to-DC power supplies. It is an isolated-flyback power-supply controller that provides Constant-Voltage (CV) using an optical coupler to improve transient response to large-load steps. This device processes information from opto-coupled feedback and an auxiliary flyback winding for high-performance control of output voltage and current.

The UCC28742 employs advanced control algorithms to achieve high operating efficiency and performance. The drive output interfaces to a MOSFET power switch. Discontinuous conduction mode (DCM) with valley-switching reduces switching losses. Modulation of switching frequency and primary current-peak amplitude (FM and AM) keeps the conversion efficiency high across the entire load and line ranges.

The controller has a maximum switching frequency of 80 kHz and always maintains control of the peak-primary current in the transformer. A minimum switching frequency of 200 Hz facilitates the achievement of low no-load input power.

open-in-new Find other Flyback controllers
Download

Technical documentation

= Top documentation for this product selected by TI
No results found. Please clear your search and try again. View all 5
Type Title Date
* Datasheet UCC28742 High-Efficiency Flyback Controller with Optocoupler Feedback datasheet (Rev. A) May 08, 2018
Application note Minimize Standby Consumption for UCC287XX Family Aug. 01, 2019
Technical articles Choosing the right flyback controller for your design Aug. 24, 2018
Application note Selecting Electrolitic Bus Capacitor for Universal Input Jul. 17, 2018
User guide Using the UCC28742EVM-001 (Rev. B) Jun. 06, 2018

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Hardware development

EVALUATION BOARD Download
99
Description

The UCC28742EVM-001 is a 10-W evaluation module for evaluating an off-line adapter for USB applications. The EVM meets CoC tier 2 and DoE Level 6 efficiency and standby power requirements. It is intended for evaluation purposes and is not intended to be an end product. The UCC28742EVM-001 converts (...)

Features
  • Opto-coupled feedback for constant output voltage operation
  • Brick-wall current limit, with +/- 5% accuracy, and timeout delay hiccup, over current protection.
  • Enables +/- 1% output voltage regulation
  • Resonant valley switching for reduced switching losses and high effiency
  • Frequency dithering to reduce (...)

Design tools & simulation

SIMULATION MODEL Download
SLUJ001A.ZIP (840 KB) - SIMPLIS Model
CALCULATION TOOL Download
SLUC652B.ZIP (301 KB)

Reference designs

Many TI reference designs include the UCC28742 Use our reference design selection tool to review and identify designs that best match your application and parameters.

CAD/CAE symbols

Package Pins Download
SOT-23 (DBV) 6 View options

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring

Recommended products may have parameters, evaluation modules or reference designs related to this TI product.

Support & training

TI E2E™ forums with technical support from TI engineers

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​

Videos

Related videos