The UCC28781 is a zero-voltage-switching (ZVS) controller which can be used at very high switching frequencies to minimize the size of the transformer and enable high power density.

With direct synchronous rectifier (SR) control, the controller does not need a separate SR controller, as it can drive the SR FET directly to maximize efficiency and simplify design. (For isolated applications, an isolated gate-driver IC is required.)

Using adaptive dead-time control for ZVS, switching losses and EMI are minimized. This design results in a controller with extremely high conversion efficiency across the entire operating range.

The programmable adaptive burst mode (ABM) gives flexibility to control when the controller enters and exits standby mode to optimize standby power in light and no-load conditions. ABM also helps to reduce ripple and minimize audible noise.

The controller offers multiple protection modes with automatic restart (retry) responses.

• Switching frequency: > 500 kHz
• Enables peak efficiency > 93 %
• Enables < 45 mW stand-by power
• Adaptive control for zero-voltage-switching (ZVS) and dead-time optimization
• EMI frequency-dithering without trade-offs on transient response or audible noise
• Programmable adaptive burst mode (ABM) with internal compensation
• X-capacitor discharge capability
• Over-temperature, overvoltage, output short-circuit, overcurrent, over-power, and pin-fault protections
• Auto-recovery fault-responses
• 4 mm × 4 mm, 24-pin, QFN package

• Control mode
• Secondary-side regulation
• Frequency (Max) (kHz)
• 1500
• UVLO thresholds on/off (V)
• 17/10.5
• Features
• SSR, Zero Voltage Switching, OVP, Adaptive Burst Mode, X-Cap Discharge
• Operating temperature range (C)
• -40 to 125
• Rating
• Catalog
• Device type
• Controllers
• Topology
• Flyback

UCC28781的完整型号有：UCC28781ARTWR，以下是这些产品的关键参数及官网采购报价：

UCC28781ARTWR，工作温度：-40 to 125，封装：WQFN (RTW)-24，包装数量MPQ：3000个，MSL 等级/回流焊峰值温度：Level-2-260C-1 YEAR，引脚镀层/焊球材料：NIPDAU，TI官网UCC28781ARTWR的批量USD价格：.65（1000+）

UCC28781EVM-053 — 适用于 UCC28781-Q1 汽车类 500Vdc 输入 ZVS 反激式电源应用的评估模块

UCC28781EMV-053 展示了采用零电压开关反激式 (ZVSF) 控制器的高效率、高密度、高电压汽车偏置电源，具有 60W、15V 输出。UCC28781-Q1 直接驱动初级侧硅 MOSFET，并通过 UCC5304 隔离式栅极驱动器驱动次级侧同步整流器，用于提高效率并实现 ZVS。