Texas Instruments UCC28742DBVR | Demoboard PMP21462.2

Beschreibung

The UCC28742 off-line flyback controller is a highlyintegrated, 6-pin secondary-side regulated PWMcontroller for efficient AC-to-DC power supplies. It isan isolated-flyback power-supply controller thatprovides Constant-Voltage (CV) using an opticalcoupler to improve transient response to large-loadsteps. This device processes information from opto-coupled feedback and an auxiliary flyback winding forhigh-performance control of output voltage andcurrent.The UCC28742 employs advanced control algorithmsto achieve high operating efficiency and performance.The drive output interfaces to a MOSFET powerswitch. Discontinuous conduction mode (DCM) withvalley-switching reduces switching losses. Modulationof switching frequency and primary current-peakamplitude (FM and AM) keeps the conversionefficiency high across the entire load and line ranges.The controller has a maximum switching frequency of80 kHz and always maintains control of the peak-primary current in the transformer. A minimumswitching frequency of 200 Hz facilitates theachievement of low no-load input power.

Eigenschaften

• 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

Typische Anwendungen

• Industrial and Medical AC-to-DC Power Supplies,Bias Supply for UPS, Server PSU, etc,Power Supply for Cable Modem, Television, Set-Top Box, and Wireless Routers, AC-to-DC Power Supply for Appliances
• Smart Electricity Meters

Weiterführende Informationen

• Datenblatt
• Produktseite des IC-Herstellers