TIDA-01579高效低波紋輸出電源參考設(shè)計(jì)

　　TI公司的TIDA-01579是采用TPS6282x系列等的高效低波紋輸出電源參考設(shè)計(jì)，采用 DCS-Control?拓拓，輸出電流高達(dá)3A（TPS62823），26/25mΩ內(nèi)部功率開(kāi)關(guān)，非常低的靜態(tài)電流4 μA，典型開(kāi)關(guān)頻率2.2MHz，可調(diào)輸出電壓從0.6V到4V，1%反饋電壓精度，100%占空比，內(nèi)部有軟起動(dòng)電路，主要用在手持/電池供電設(shè)備的POL電源，工廠和建筑物自動(dòng)化，移動(dòng)計(jì)算和網(wǎng)絡(luò)卡，固態(tài)驅(qū)動(dòng)，數(shù)據(jù)終端和POL.本文介紹了參考設(shè)計(jì)TIDA-01579主要特性和指標(biāo)，框圖，電路圖，材料清單和PCB設(shè)計(jì)圖。

　　The TPS6282x is an all-purpose and easy to usesynchronous step-down DC-DC converter with a verylow quiescent current of only 4μA. It supplies up to3A output current （TPS62823） from a 2.4V to 5.5Vinput voltage. Based on the DCS-Control? topologyit provides a fast transient response.

　　The internal reference allows to regulate the outputvoltage down to 0.6V with a high feedback voltageaccuracy of 1% over the junction temperature rangeof -40℃ to 125℃。 The 1，2，3A scalable pin-to-pin andBOM-to-BOM compatible device family can be used with small 470nH inductors.

　　The TPS6282x include an automatically enteredpower save mode to maintain high efficiency down tovery light loads.

　　The device features a Power Good signal and aninternal soft start circuit. It is able to operate in 100%mode. For fault protection， it incorporates a HICCUPcurrent limit as well as a thermal shutdown.

　　The TPS6282x are packaged in a 2 x 1.5mm QFN-8package.

　　參考設(shè)計(jì)TIDA-01579主要特性：

　　? DCS-Control? topology

　　? 26/25mΩ Internal Power Switches （TPS62823）

　　? Up to 3A Output Current （TPS62823）

　　? Very Low Quiescent Current of 4 μA

　　? Switching Frequency of typically 2.2 MHz

　　? 1% Feedback Voltage Accuracy （full temp. range）

　　? Enable （EN） and Power Good （PG）

　　? Adjustable Output Voltage from 0.6 V to 4V

　　? 100% Duty-Cycle Mode

　　? Internal Soft-Start Circuitry

　　? Seamless Power Save Mode Transition

　　? Undervoltage Lockout

　　? Active Output Discharge

　　? Cycle-by-Cycle Current Limit

　　? HICCUP Short-Circuit Protection

　　? Over Temperature Protection

　　? Create a Custom Design using the TPS62822 withthe WEBENCH? Power Designer

　　參考設(shè)計(jì)TIDA-01579應(yīng)用：

　　? POL supply in Portable/Battery Powered Devices

　　? Factory and Building Automation

　　? Mobile Computing， Networking Cards

　　? Solid State Drive

　　? Data Terminal， Point of Sale

　　? Servers， Projectors， Printers

　　圖1.參考設(shè)計(jì)TIDA-01579框圖

　　圖2.TPS62822應(yīng)用電路：2.4V-5.5V 2A電源

　　The point-of-load power-tree on video surveillancesystems is optimized with this reference design. Thisreference design has a high performance on keyparameters such as output voltage accuracy， voltageripple， and thermal dissipation. This high performance is possible with a small board area and low BOM cost.

　　The design operates from a 5-V supply commonlyfound in video doorbells， IP network cameras， andwireless cameras.

　　Video doorbells provide a set of features common to many traditional video surveillance devices. Thisdistinguishing feature demands a unique power design to ensure trouble-free operation from theubiquitous， but widely-varying， AC doorbell supply. To fully utilize an AC source that presents a substantialbottleneck， the power design should be as efficient as possible. This design uses TI’s new synchronousbuck converters and LDOs providing a complete and customizable supply optimized for video doorbells.

　　Our newest converters in QFN and SOT-563 packages allow for a supply design that requires minimalboard space and has a low thermal impact—both of which are needed for smaller form factor electronics.For better compatibility， sequencing is possible for all rails.

　　IP network cameras have increasing image resolution， processing， and illumination requirements while stillfitting in small enclosures. After stepping down from a mid- to high-voltage DC power source such as pluginpower or PoE， the system demands point-of-load conversion with high efficiency and a small footprint.

　　Both efficiency and footprint are important to accommodate small enclosures with， typically， less-thanadequateventilation. This design is optimized for both efficiency and footprint while also providing theflexibility to tailor to more advanced， power-demanding loads， such as a dedicated image recognitionprocessor or 4K video processor.

　　Wireless or battery-powered cameras require high efficiency at both full loads and light loads. Thesecameras typically employ motion detection， human interface， or wireless communications monitoring， orany combination of the three， to minimize time spent in power-hungry states quiescent currents andshutdown currents of subsystems are very important as these standby currents can have significantimpact on overall battery life. The TIDA-01579 reference design has been optimized for this application byutilizing TI’s low-power converters featuring both light load efficiency and shutdown with low Iq. Convertershutdown and low-Iq load switches can be used to cut power to subsystems with less-than-desirablestandby consumption—saving cost and extending battery life.

　　參考設(shè)計(jì)TIDA-01579主要特性：

　　? 1% Typical output voltage accuracy

　　? High system efficiency to 90% at full load

　　? Voltage ripple 《 60-μV， useful for noise-criticalperipherals

　　? Thermal hot spot is 《 45℃ at full load current

　　? Small PCB real estate

　　? Low BOM cost

　　參考設(shè)計(jì)TIDA-01579應(yīng)用：

　　? Video Doorbell

　　? IP Network Camera

　　? Wireless camera

　　? Thermal Imaging Camera

　　? Analog Security Camera

　　圖3.參考設(shè)計(jì)TIDA-01579外形圖

　　參考設(shè)計(jì)TIDA-01579系統(tǒng)主要指標(biāo)：

　　圖4.參考設(shè)計(jì)TIDA-01579框圖

　　圖5.參考設(shè)計(jì)TIDA-01579電路圖（1）

　　圖6.參考設(shè)計(jì)TIDA-01579電路圖（2）

　　圖7.參考設(shè)計(jì)TIDA-01579電路圖（3）

　　參考設(shè)計(jì)TIDA-01579材料清單：

　　圖8.參考設(shè)計(jì)TIDA-01579 PCB設(shè)計(jì)圖（1）

　　圖9.參考設(shè)計(jì)TIDA-01579 PCB設(shè)計(jì)圖（2）

　　圖10.參考設(shè)計(jì)TIDA-01579 PCB設(shè)計(jì)圖（3）

　　圖11.參考設(shè)計(jì)TIDA-01579 PCB設(shè)計(jì)圖（4）

　　圖12.參考設(shè)計(jì)TIDA-01579 PCB設(shè)計(jì)圖（5）

　　圖13.參考設(shè)計(jì)TIDA-01579 PCB設(shè)計(jì)圖（6）

　　圖14.參考設(shè)計(jì)TIDA-01579 PCB設(shè)計(jì)圖（7）

　　圖15.參考設(shè)計(jì)TIDA-01579 PCB設(shè)計(jì)圖（8）