STEF512PUR - Dual eFuse 5V/12V 3A Hot-Swap | STMicroelectronics
料号： STEF512PUR ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $1.85 | $1.85 |
| 10 | $1.65 | $16.50 |
| 100 | $1.42 | $142.00 |
| 500 | $1.22 | $610.00 |
| 1,000 | $1.08 | $1,080.00 |
| 3,000 | $0.95 | $2,850.00 |
STEF512PUR 概述
An electronic fuse (eFuse) is a solid-state replacement for a traditional thermal fuse or PTC, offering resettable, programmable protection with fast fault response. It belongs to the broader family of hot-swap controllers and current regulators within power-management ICs (PMICs). The eFuse architecture allows precise user-adjustable startup behavior via external soft-start capacitors and current-limit thresholds via sense resistors, eliminating the need for bulky mechanical fuses in space-constrained designs.
Key features include independent fault timers, thermal shutdown, UVLO and OVLO protection per channel, a Fault flag output for system-level diagnostics, and adjustable slew-rate control. Each eFuse channel operates independently, allowing the 5 V and 12 V rails of a system to be protected, sequenced, and monitored separately without external coordination logic. The integrated MOSFETs drastically reduce BOM count compared to discrete hot-swap solutions built from FETs, op-amps, and sense resistors.
Typical applications include hot-swap insertion in rack-mounted servers, SSD and HDD power-rail protection, set-top box and consumer-electronics load switches, USB Type-C VBUS current limiting, and industrial 24 V backplane protection when paired with a pre-regulator. The dual-rail architecture is particularly efficient in ATX-style PC subsystems and small-form-factor systems that need both 5 V standby and 12 V main rail protection.
A critical design consideration is the choice of soft-start capacitor, which sets the inrush-current profile and the fault-timer timeout. Engineers should also account for the package's thermal resistance — at full 3 A per channel, sufficient copper pour is required to keep junction temperature within the datasheet limits.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
直接替换替代料： STEF512PUR ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
STEF512PUR
✅ 直接替换✓ 有现货
$0.95 / 个
查看数据手册 →STEF12HOLD
✅ 直接替换📋 参考替代料（不在目录中）
STEF12HPUR
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
STEF512PUR 规格参数
| 功能 | Dual electronic fuse (eFuse), high-side load switch |
| Number of Channels | 2 (independent) |
| Channel 1 Nominal Rail | 5 V |
| Channel 2 Nominal Rail | 12 V |
| Maximum Continuous Current (per channel) | 3 A |
| 拓扑 | High-side integrated MOSFET |
| Protection Features | Overcurrent, overvoltage, thermal shutdown, UVLO, OVLO |
| Fault Output | Yes (FAULT flag) |
| Soft-Start Adjustable | Yes (external capacitor per channel) |
| Current Limit Adjustable | Yes (external sense resistor per channel) |
| 工作温度范围 | -40 C to +125 C |
| 封装 | 10-QFN (2 mm x 3 mm) |
| 安装类型 | Surface Mount |
| RoHS 状态 | Compliant |
STEF512PUR 引脚配置
| 引脚 1 | VIN1 — 5 V rail input for eFuse channel 1 |
| 引脚 2 | VOUT1 — 5 V rail output for eFuse channel 1 |
| 引脚 3 | SS1 — Soft-start capacitor for channel 1 |
| 引脚 4 | ILIM1 — Current-limit sense for channel 1 |
| 引脚 5 | GND — Ground |
| 引脚 6 | ILIM2 — Current-limit sense for channel 2 |
| 引脚 7 | SS2 — Soft-start capacitor for channel 2 |
| 引脚 8 | VOUT2 — 12 V rail output for eFuse channel 2 |
| 引脚 9 | VIN2 — 12 V rail input for eFuse channel 2 |
| 引脚 10 | FAULT — Open-drain fault flag output |
典型应用
STEF512PUR 适用于 6 应用s: Server and Storage Hot-Swap Protection, SSD and M.2 Module Power-Rail Protection, Set-Top Box and Consumer Load Switches, Industrial Backplane and 24 V Pre-Regulated Rails, USB Type-C and Powered-USB VBUS Limiting, Automotive Infotainment and Body Electronics.
Server and Storage Hot-Swap Protection
The STEF512PUR's dual 3 A eFuse channels make it ideal for hot-swap insertion protection on 5 V standby and 12 V main rails in rack-mounted servers, disk arrays, and hot-pluggable storage modules. Each channel independently limits inrush current via a programmable soft-start capacitor, eliminating the connector arcing and downstream capacitor inrush that can cause voltage sags during board insertion. The integrated FAULT flag lets the BMC log events and disable the slot before catastrophic failure. Compared to discrete hot-swap controllers using external FETs, the STEF512PUR saves roughly 50% of board area, which is critical in dense 1U server backplanes where both rails must be protected simultaneously.
推荐
SSD and M.2 Module Power-Rail Protection
In M.2 SSD and removable storage designs, the STEF512PUR protects the host 5 V and 12 V rails (when applicable) from short circuits and overcurrent events caused by connector contamination, ESD-induced latch-up, or field failures. The 10-QFN (2 mm x 3 mm) package is small enough to fit next to the M.2 connector without exceeding the module's z-height. With 3 A per channel, the part easily handles the 2 A to 2.5 A peaks drawn by NVMe SSDs under sustained write load. The OVLO function protects the NAND controller from upstream voltage transients, an increasingly common failure mode in portable systems.
推荐
Set-Top Box and Consumer Load Switches
Set-top boxes, smart TVs, and home gateways commonly distribute both 5 V standby and 12 V main power to internal modules. The STEF512PUR integrates both rails into a single IC, dramatically simplifying the power tree compared to two discrete eFuse ICs. Its adjustable current limit lets a designer size the protection to match each downstream module — 1.5 A for a Wi-Fi subsystem, 3 A for the main SoC rail. The shared FAULT pin gives the host CPU a single interrupt source for both rails, reducing GPIO usage and simplifying firmware. The 10-QFN footprint also fits within the height profile of slim consumer enclosures.
推荐
Industrial Backplane and 24 V Pre-Regulated Rails
When paired with a downstream 5 V and 12 V post-regulator fed from a 24 V industrial bus, the STEF512PUR protects the secondary rails from overcurrent events caused by field wiring shorts or load dump transients. Each eFuse channel operates independently, so a fault on one rail does not affect the other — critical for maintaining partial system operation in industrial PLCs and motor controllers. The OVLO feature clamps input voltage spikes that may propagate from the upstream switching converter, while thermal shutdown protects the device when operating at the 3 A limit in high-ambient-temperature enclosures.
推荐
USB Type-C and Powered-USB VBUS Limiting
The STEF512PUR's 5 V channel serves as a programmable VBUS current limiter in USB Type-C downstream-facing ports and PoweredUSB applications. The 3 A continuous rating exceeds the default USB Type-C 1.5 A and 3 A current profiles, while the soft-start control prevents the VBUS voltage collapse that can confuse USB PD negotiation during hot-attach. The FAULT pin alerts the USB controller to overcurrent events so it can signal the appropriate USB PD message. For designs requiring full 5 A USB PD support, the STEF512PUR can be combined with a USB PD controller in a two-stage protection topology.
推荐
Automotive Infotainment and Body Electronics
Although not AEC-Q100 qualified, the STEF512PUR is used in non-safety automotive body electronics and infotainment sub-modules where 5 V and 12 V rails must be protected from short-to-ground and load-dump events. Its -40 C to +125 C operating range covers the full automotive cabin temperature window. The integrated FAULT output enables diagnostic logging required by OEM service procedures, while the small 10-QFN package fits behind the head unit display where board area is constrained. Designers targeting AEC-Q100 should evaluate the STEF12-Q1 family or alternate AEC-Q100 qualified eFuses.
推荐
推荐产品汇总
工程参考数据： STEF512PUR ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | STEF12HOLD | STEF12HPUR |
|---|---|---|---|
| Package | 10-QFN (2x3 mm) | 10-QFN (2x3 mm) - same | 10-QFN (2x3 mm) - same |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics |
| Number of Channels | 2 (independent) | 2 (independent) | 2 (independent) |
| Nominal Rail Voltages | 5 V + 12 V | 5 V + 12 V | 5 V + 12 V |
| Continuous Current per Channel | 3 A | 3 A | 3 A |
| Fault Behavior | Latching off | Hold last state (auto-retry) | Latching off |
| FAULT Output Pin | Yes (open-drain) | Yes (open-drain) | Yes (open-drain) |
| Soft-Start Adjustable | Yes (external cap) | Yes (external cap) | Yes (external cap) |
| Operating Temperature | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C |
关键差异点
- Dual independent 5 V + 12 V eFuses in a single 10-QFN (2x3) （对比 TI TPS2595 single-rail eFuse)
- Programmable fault recovery options across the STEF512 family （对比 STEF12HOLD)
- Integrated FAULT flag for both rails （对比 STEF12HPUR)
设计说明
Estimated: at 3 A continuous per channel with VIN-VOUT drop of approximately 50 mV, each channel dissipates roughly 0.15 W. Combined 0.30 W in the 10-QFN (2x3) requires a minimum copper-pour area of approximately 100 mm² on the top layer and thermal vias to the inner plane to stay below the 125 C junction limit at 70 C ambient. Always refer to the STMicroelectronics datasheet thermal-resistance section for the exact theta_JA value used in your layout.
Place the ILIM sense resistors within 2 mm of the corresponding ILIM pins to minimize parasitic inductance. Use a Kelvin connection (separate force and sense traces) for best current-limit accuracy. The exposed thermal pad must be soldered to a contiguous ground pour with at least four thermal vias (0.3 mm diameter) connecting to the inner ground plane for low thermal impedance.
Do not leave the SS pins floating — always connect a soft-start capacitor (typically 10 nF to 100 nF) to GND. A floating SS pin causes undefined startup behavior and may prevent the eFuse from exiting its UVLO state. Likewise, do not exceed the absolute maximum VIN rating per channel or apply reverse polarity; the integrated FETs are not reverse-blocking and require external protection if reverse-voltage fault conditions are possible.
合规信息
RoHS compliant per ST product page. Not AEC-Q100 qualified; for automotive applications use the STEF12-Q1 family or an AEC-Q100 qualified alternate.
