封裝資訊
| 封裝 | 引腳 SOT-23 (DBV) | 6 |
| 作業溫度範圍 (°C) -40 to 125 |
| 包裝數量 | 運送包裝 250 | SMALL T&R |
UCC28742 的特色
- 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
UCC28742 的說明
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.