UCC28742

ACTIVE

High-Efficiency Flyback Controller with 1% Output regulation accuracy

Product details

Operating temperature range (°C) -40 to 125 Control mode Secondary-side regulation Topology Flyback Rating Catalog
Operating temperature range (°C) -40 to 125 Control mode Secondary-side regulation Topology Flyback Rating Catalog
SOT-23 (DBV) 6 8.12 mm² 2.9 x 2.8
  • 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
  • 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

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.

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.

Download View video with transcript Video

Similar products you might be interested in

open-in-new Compare alternates
Same functionality with different pin-out to the compared device
NEW UCC28750 ACTIVE Current-mode flyback controller with secondary-side regulation (SSR) for offline applications Same functionality with different pin-out to the compared device

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 14
Type Title Date
* Data sheet UCC28742 High-Efficiency Flyback Controller with Optocoupler Feedback datasheet (Rev. A) PDF | HTML 08 May 2018
Technical article 단일 커패시터를 추가하여 듀얼 출력 플라이백 전원 공급 장치의 교차 조정 개선 PDF | HTML 22 Mar 2024
Technical article 플라이백 컨버터 스너빙 PDF | HTML 22 Mar 2024
Technical article 新增單一電容器以增進雙輸出返馳電源供應器的交互穩壓 PDF | HTML 20 Mar 2024
Technical article 緩衝返馳式轉換器 PDF | HTML 20 Mar 2024
Technical article Snubbing the flyback converter PDF | HTML 26 Feb 2024
Technical article Adding a single capacitor to improve cross-regulation in dual-output flyback power supplies PDF | HTML 21 Dec 2023
Application brief Flyback Selection Guide PDF | HTML 23 Jun 2022
Application note Flyback Aux Winding OVP and UVLO Fault Sensing Design and Troubleshooting Tips PDF | HTML 31 Aug 2021
More literature PCB layout guidelines to optimize power supply performance 23 Mar 2021
Application note Minimize Standby Consumption for UCC287XX Family 01 Aug 2019
Technical article Choosing the right flyback controller for your design PDF | HTML 24 Aug 2018
Application note Selecting Electrolitic Bus Capacitor for Universal Input 17 Jul 2018
EVM User's guide Using the UCC28742EVM-001 (Rev. B) 06 Jun 2018

Design & development

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

Evaluation board

UCC28742EVM-001 — UCC28742 10W AC/DC Converter Evaluation Module

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 (...)

User guide: PDF
Not available on TI.com
Simulation model

UCC28742 SIMPLIS Model (Rev. A)

SLUJ001A.ZIP (840 KB) - SIMPLIS Model
Calculation tool

SLUC652 UCC28742 Design Calculator

Supported products & hardware

Supported products & hardware

Products
AC/DC & DC/DC controllers (external FET)
UCC28742 High-Efficiency Flyback Controller with 1% Output regulation accuracy

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.

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
Information included:
  • Fab location
  • Assembly location

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