TPS23755RJJR - IEEE 802.3at PoE PD with Flyback Controller | TI
MPN： TPS23755RJJR ✓ 啟用中TPS23755RJJR 概覽
A PoE powered device interface is the front-end circuit that negotiates and extracts power from a Power Sourcing Equipment (PSE) port such as a PoE switch or injector, according to the IEEE 802.3at standard. Within the power-management hierarchy, it sits between the Ethernet cabling and the isolated flyback converter that generates the system's low-voltage rails, combining classification, inrush control, hot-swap protection, and switching regulation in one IC.
Key features include full 802.3at Type 1 (13 W) PD compliance, an integrated 150-V power MOSFET that eliminates the external pass switch, and current-mode flyback control with primary-side regulation (PSR). PSR removes the optocoupler and secondary-side reference, cutting component count and board area while improving reliability in isolated designs.
Technically, the device employs spread spectrum frequency dithering (SSFD) to reduce conducted EMI peaks, easing filter design toward CISPR compliance. Advanced startup circuitry supports operation from the PoE detection and classification voltage range before full power is available, and the current-mode architecture provides inherent cycle-by-cycle current limiting and simple loop compensation for the flyback power stage.
Typical applications include IP security cameras, wireless access points, VoIP phones, and networked LED lighting luminaires - all space-constrained PoE endpoints where a single-chip PD interface plus converter saves measurable board area. The high integration level makes it especially attractive for compact, cost-sensitive camera modules.
Design consideration: because the power FET is integrated, PCB copper area under the VSON exposed pad is the main thermal path; size the transformer and demagnetization timing so PSR sampling windows are honored, and verify EMI with SSFD enabled before final layout freeze.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
直接替換替代品，適用於 TPS23755RJJR — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： TPS23755RJJR （相同外形與佔位） — 差異在於 Function, Package, PoE Standard, Evaluation Module, Output Power Class.
TPS23754RJJR
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
TPS23753ARJJR
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
TPS23755RJJR 最大額定值與電氣特性
| 功能 | IEEE 802.3at PoE PD interface with no-opto flyback DC-DC controller |
| PoE Standard | IEEE 802.3at (Type 1, 13 W class) |
| 通道數 | 1 |
| Integrated Power FET | Yes, 150 V switching MOSFET |
| Regulation Topology | Current-mode flyback, primary-side regulation (PSR) |
| Optocoupler Requirement | None (no-opto design) |
| EMI Reduction | Spread spectrum frequency dithering (SSFD) |
| Startup Feature | Advanced startup |
| 封裝 | 24-VSON (6x4 mm) |
| 安裝類型 | Surface Mount |
| Output Power Class | Type 1 PoE (13 W) |
| Evaluation Module | TPS23755EVM-894 |
| Reel Variant | TPS23755RJJT |
TPS23755RJJR 24-vson (6x4 mm) 腳位配置指南
TPS23755RJJR（24-vson (6x4 mm) 封裝）的腳位配置。 此功率元件具有閘極、汲極與源極端子。對於非極性封裝，請參閱製造商資料表以取得確切的第 1 腳方向與佈局詳細資訊。常見應用包括電源設計、馬達驅動與負載切換。
無詳細腳位定義資料： TPS23755RJJR.
請參閱 資料表 以查看完整腳位配置。
典型應用
TPS23755RJJR 適用於 6 應用s: IP Security Cameras, Wireless Access Points, VoIP Desk Phones, PoE LED Lighting Luminaires, Networked Building Sensors and Controllers, Intercoms and Door Entry Systems.
IP Security Cameras
Networked surveillance cameras are the canonical 802.3at Type 1 PoE endpoint, drawing image-sensor, ISP, and network power from the Ethernet cable. The TPS23755RJJR fits this application because its integrated 150-V FET and no-opto PSR flyback controller produce an isolated 13 W supply from the PoE port in minimal board area, a decisive constraint inside compact dome or bullet camera housings. Spread spectrum frequency dithering lowers conducted EMI peaks near the sensitive video front-end and Ethernet PHY, simplifying filter design. Placed directly after the RJ45 diode bridge, the PD interface handles detection, classification, and inrush while the flyback stage generates the 3.3 V/5 V system rails, trading a slightly larger transformer for the elimination of the optocoupler and secondary reference.
推薦
Wireless Access Points
Ceiling-mounted Wi-Fi access points rely on PoE because running separate power cabling to ceilings is costly. A single-band or small dual-band AP typically falls within the 802.3at Type 1 13 W budget that the TPS23755RJJR serves. The device negotiates power with the PSE, controls inrush, and converts the 37-57 V PoE input into the 5 V or 3.3 V rails feeding the radio SoC and Ethernet magnetics. Its no-opto primary-side regulation removes a reliability-sensitive component from a unit that must run unattended for years at elevated ceiling temperatures, while the integrated 150-V FET avoids an extra high-voltage SMD part, shrinking the power section and cutting BOM cost per unit in volume access-point production.
推薦
VoIP Desk Phones
Enterprise VoIP phones classically power themselves from the desk Ethernet drop, making the PoE PD interface a mandatory front-end. The TPS23755RJJR provides the 802.3at detection and classification signature plus a compact isolated flyback converter, delivering speaker, handset, display, and phone-controller power within the 13 W Type 1 envelope. Primary-side regulation eliminates the optocoupler and its aging-related CTR drift, supporting the long service life and low warranty-return expectations of enterprise telephony. Spread spectrum dithering helps the design meet office conducted-emissions limits without bulky filtering near the audio path. Advanced startup ensures clean power-up sequencing from the PoE classification voltage before the main converter begins switching.
推薦
PoE LED Lighting Luminaires
Networked LED luminaires increasingly use PoE for both power and control in smart-building installations. The TPS23755RJJR serves Type 1 (13 W) fixtures such as downlights and accent lighting: its PD interface negotiates power from the PoE switch while the integrated 150-V FET and no-opto flyback controller convert the port voltage to a LED-friendly DC rail. Primary-side regulation removes the optocoupler, reducing component count inside thermally constrained luminaire housings, and spread spectrum frequency dithering suppresses EMI peaks that could couple into dimming control lines. The isolated flyback topology provides safety isolation between the Ethernet-powered input and the accessible LED string, an important consideration in commercial ceiling installations.
推薦
Networked Building Sensors and Controllers
Occupancy sensors, access-control readers, HVAC zone controllers, and other ceiling- or wall-mounted building devices benefit from PoE because a single Category cable delivers both connectivity and power. The TPS23755RJJR supplies the complete 802.3at Type 1 front end plus a compact isolated converter, generating clean 5 V or 3.3 V rails from the PoE port for the microcontroller and sensors. Its integrated 150-V power FET and no-opto PSR architecture keep the power section small enough for slim enclosures, while spread spectrum dithering minimizes conducted emissions near sensitive analog sensor front-ends. Advanced startup supports reliable reconnection after switch power cycling, and hot-swap inrush control protects both the device and the upstream PSE port electronics.
推薦
Intercoms and Door Entry Systems
PoE-powered door stations, video intercoms, and entry controllers draw speaker, camera, and lock-actuation power from the building Ethernet infrastructure. The TPS23755RJJR handles the 802.3at Type 1 PD negotiation and converts port power through an isolated no-opto flyback, delivering up to 13 W for the system rails. Primary-side regulation suits outdoor and vandal-resistant enclosures where long unattended service life is required, since the optocoupler - a common aging failure point - is eliminated. Spread spectrum frequency dithering reduces conducted EMI near the audio amplifier and camera circuitry, easing compliance testing. The integrated 150-V FET supports the full PoE input voltage range with margin, and the compact VSON-24 package fits flat door-station form factors.
推薦
推薦產品摘要
工程參考資料，適用於 TPS23755RJJR — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | TPS23754RJJR | TPS23753ARJJR |
|---|---|---|---|
| Package | 24-VSON (6x4 mm) | 24-VSON (6x4 mm) - same | 24-VSON (6x4 mm) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments |
| PoE Standard | IEEE 802.3at Type 1 (13 W) | IEEE 802.3at Type 1 (13 W) | IEEE 802.3at Type 1 (13 W) |
| Integrated Power FET | Yes, 150 V | Yes, 150 V | Yes, 150 V |
| Feedback Method | Primary-side regulation (no-opto) | PSR plus opto/auxiliary topology support | Secondary-side (opto) flyback |
| Optocoupler Required | No | Optional (design dependent) | Yes |
主要差異化特點
- No-opto primary-side regulation (PSR) (對比TPS23753ARJJR)
- Flexible topology support within the same footprint (對比TPS23754RJJR)
- EMI performance via spread spectrum dithering (對比TPS23753ARJJR)
設計說明
The TPS23755RJJR integrates a 150-V power FET, so the VSON-24 exposed pad is the primary thermal path for both the switching losses and conduction losses of the flyback stage. Provide a solid array of thermal vias from the exposed pad to inner and bottom copper layers, sized per the PCB layout guidelines in the manufacturer datasheet. Estimated: at a 13 W Type 1 load with roughly 85% converter efficiency, about 2.3 W is dissipated, so verify junction temperature against the datasheet thermal resistance with your actual PCB copper area before finalizing the layout.
Keep the primary-side hot loop (integrated FET, transformer primary, and sense resistor path) as small as possible to minimize radiated emissions, and place the PSR sensing network directly at the transformer auxiliary winding with short, low-inductance traces - PSR regulation accuracy depends on a clean demagnetization sampling window. Follow the TPS23755EVM-894 reference layout for transformer placement and ground partitioning between PoE input (hot) and controller grounds.
Enable spread spectrum frequency dithering (SSFD) during pre-compliance testing; it spreads the switching harmonics and typically lowers peak conducted emissions, allowing a smaller input filter. However, remember that dithering spreads energy across the band, so average-detector measurements near class limits also rise - validate with both peak and average detectors per your lab procedure. Choose the transformer for proper demagnetization timing so PSR output-voltage sampling occurs on the correct plateau.
Do not assume interoperability with the TPS23754/TPS23753A without checking the feedback architecture: the TPS23755 is a no-opto PSR design, so an existing opto-based flyback transformer winding arrangement may not be reusable without redesign. Also verify that your PoE classification resistor settings and inrush capacitor values match the 802.3at Type 1 power class required by your end equipment, as undersized classification signatures cause PSE power denial.
合規資訊
Compliance status was not stated in the provided web data; confirm RoHS/REACH and lead-free status on the TI product page at ti.com/product/TPS23755 before ordering.
