TI 公司的UCC24610是5V系統(tǒng)的綠色整流控制器，當(dāng)采用單獨(dú)電源時(shí)LLC輸出可高達(dá)15V，工作頻率高達(dá)600kHz，VDS MOSFET電流檢測(cè)，能從輕負(fù)載和睡眠模式中同步叫醒，主要用在AC/DC 5V適配器，5V偏壓電源，低壓整流電路和反激和LLC轉(zhuǎn)換器。本文介紹了UCC24610主要特性，功能方框圖，反激拓?fù)淇驁D和LLC串聯(lián)諧振轉(zhuǎn)換器框圖，以及變壓器配置，自同步配置和電容配置的LLC串聯(lián)諧振轉(zhuǎn)換器電路圖和相應(yīng)的材料清單。

　　A 90-W, High-Efficiency, LLC Series-Resonant Converter with Secondary-Side Synchronous Rectification

　　The UCC24610 Green Rectifier Controller is optimized for 5-V systems and can be used for LLC outputs up to 15 V when a separate 5-V supply is available. Above 15 V the UCC24610 is limited by the 50-V maximum voltage rating of the VD pin. This is because in a conventional secondary rectifier arrangement, that employs two rectifiers with a center-tapped secondary winding, each rectifier sees a peak reverse voltage equal to twice the regulated output.

　　The scope of this reference design guide is to describe the design and performance of a functional circuit that extends the application of the UCC24610 to systems with output voltages up to 30 V. This is achieved using an alternate topology for secondary rectification and addressing the design constraints that the topology presents. Two configurations are described for synchronizing the turn-off of each SR circuit using the gate-drive signals on the primary side of the converter.

　　An area not addressed by this guide is electromagnetic compatibility (EMC). For most applications, EMI filter components are added so that the design meets applicable environmental and system compatibility requirements.

　　To comply with EMC standards, components such as input and output filters are required to suppress electromagnetic interference (EMI).

　　This GREEN Rectifier™ controller is a high-performance controller and driver for standard and logic-level N-channel MOSFET power devices used for low-voltage secondary-side synchronous rectification.

　　The combination of controller and MOSFET emulates a near-ideal diode rectifier. This solution not only directly reduces power dissipation of the rectifier but also indirectly reduces primary-side losses as well, due to compounding of efficiency gains.

　　Using drain-to-source voltage sensing, the UCC24610 is ideal for Flyback and LLC-Resonant power supplies but can also be used with other power architectures. The UCC24610 is optimized for output voltages from 4.5 V to 5.5 V, and is suitable for use with lower and higher output voltages as well.

　　UCC24610主要特性：

　　Secondary-Side Controller Optimized for 5-V Systems

　　Up to 600-kHz Operating Frequency

　　VDS MOSFET-Sensing

　　1.6-ohm Sink, 2.0-ohm Source Gate-Drive Impedances

　　Micro-Power Sleep Current for 90+ Designs

　　Automatic Light-Load Management

　　Synchronous Wake-Up From Sleep and Light-Load Modes

　　Protection Features on Programming Inputs

　　SYNC Input for CCM Operation

　　20-ns Typical Turn-Off Propagation Delay

　　Improved Efficiency and Design Flexibility Over Traditional Diode Solution

　　May Be Biased Directly From 5-V Output

　　Minimal Component Count

　　UCC24610應(yīng)用：

　　AC/DC 5-V Adapters

　　5-V Bias Supplies

　　Low Voltage Rectification Circuits

　　Flyback and LLC Converters

　　圖1。UCC24610功能方框圖

　　圖2。UCC24610反激拓?fù)淇驁D

　　圖3。UCC24610 LLC諧振半橋框圖

　　圖4。UCC24610采用初級(jí)MOSFET漏極驅(qū)動(dòng)SYNC輸入電路圖

　　圖5。UCC24610 LLC串聯(lián)諧振轉(zhuǎn)換器框圖

　　圖6。同步開關(guān)MOSFET的倍壓整流電路圖

　　圖7。UCC24610 LLC串聯(lián)諧振轉(zhuǎn)換器電路圖：自同步配置

　　圖8。UCC24610 LLC串聯(lián)諧振轉(zhuǎn)換器電路圖：變壓器配置

　　圖9。UCC24610 LLC串聯(lián)諧振轉(zhuǎn)換器電路圖：電容配置

　　自同步配置材料清單（基本電路）：

　　變壓器同步配置附加材料清單：

　　電容同步配置附加材料清單：