STMicroelectronics STEF05DPUR

Overview

STEF05DPUR from STMicroelectronics is a 5 V electronic fuse IC with N-channel MOSFET architecture, continuous current rating of 3.6 A, on-resistance of 40 mΩ (typ), and integrated output voltage clamp at 6.65 V (typ). It provides undervoltage lockout (3.6 V typ), thermal latch at 165 °C (typ), and controlled output ramp for inrush suppression - deployed in SSDs, HDDs, and set-top boxes to replace mechanical fuses.

For engineers reviewing the STEF05DPUR datasheet, STEF05DPUR pinout, STEF05DPUR application, or STEF05DPUR equivalent, key selection criteria include programmable current limiting via external resistor, tri-state Enable/Fault signaling for thermal fault detection, dv/dt-controlled turn-on timing, and DFN10 (3 × 3 mm) package compatibility with high-density PCB layouts.

Technical Context

The STEF05DPUR integrates an N-channel power MOSFET with precision current-sense FET ratio and internal dv/dt control circuitry to regulate output voltage slew rate during startup. Its enable/fault pin operates as a tri-state interface: floating or pulled high enables conduction; pulled low disables output; intermediate voltage (0.82–1.95 V) signals thermal shutdown.

Current limiting is set externally via resistor between I-Limit and Source pins, enabling precise short-circuit (3.1–5.1 A) and overload (4 A typ) thresholds. Thermal protection latches at 165 °C (typ), and recovery requires either supply recycle or active reset via Enable pin below 0.58 V.

Key Specifications

Pinout & Package

STEF05DPUR is housed in a thermally enhanced DFN10 (3 × 3 mm, 0.65 mm height) package with exposed VCC pad for improved heat dissipation. The 10-pin layout includes functional redundancy (pins 1–5 tied internally to VOUT/Source) and strict isolation of analog (I-Limit, dv/dt) and digital (En/Fault) control paths.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar electronic fuse applications.

Compared with TPS259211RGER and AP22653WU-7, STEF05DPUR uniquely combines programmable current limiting, thermal latch with explicit fault signaling, and user-adjustable dv/dt - making it optimal for industrial storage systems requiring deterministic fault handling and layout flexibility.

Availability

STEF05DPUR is available at Aetrix Electronics and suitable for solid state drives, hard disk drives, and set-top boxes requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for STEF05DPUR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, sensors, and analog devices for industrial, automotive, and consumer markets.

The STEF series is ST's dedicated electronic fuse product line, engineered specifically for high-reliability 5 V and 12 V power rail protection in storage, computing, and multimedia equipment - emphasizing programmability, thermal robustness, and system-level fault visibility.

FAQ

What is the recommended copper area for the VCC exposed pad?

The VCC pad (pin 11) must be soldered to a minimum 0.5 inch² copper area on the PCB to achieve the specified R_thJA of 52.7 °C/W. For operation at full 3.6 A continuous current, ST recommends using internal and external copper layers connected via ≥6 thermal vias (0.3 mm diameter) to maximize heat dissipation and maintain junction temperature below 125 °C.

How is the short-circuit current limit calculated?

The short-circuit current limit is set by the resistor R_Limit connected between pins 7 (I-Limit) and 1–5 (VOUT/Source). Using the formula I_Short ≈ 42 / R_Limit (with R_Limit in ohms), a 11 Ω resistor yields 3.8 A typical limit. The relationship is confirmed in Figure 13 of the datasheet and accounts for internal sense-FET ratio and process variation.

Can the En/Fault pin drive multiple devices simultaneously?

Yes - the En/Fault pin supports up to three STEF05DPUR devices connected in parallel for synchronized thermal shutdown. When one device enters thermal fault, its En/Fault pin pulls to 0.82–1.95 V, forcing all connected devices into disable state. This is validated in Section 5.4 and Figure 6 of the datasheet, with maximum fan-out specified as three units.

Does STEF05DPUR require external components for basic operation?

Yes - minimal external components are required: a resistor between I-Limit and Source pins to set current limits, and optional capacitor on dv/dt pin to extend ramp time. Input/output bulk capacitors (CI = 10 µF, CO = 47 µF) are recommended per Section 4 test conditions, but not strictly mandatory for functional operation at reduced load transients.