STMicroelectronics STIL08-T5

Overview

STIL08-T5 from STMicroelectronics is an AC inrush current limiter IC designed for off-line PFC boost pre-regulators. It integrates two unidirectional ASD power switches and a pilot driver in a Pentawatt package, delivering 8 A average output current, 800 V repetitive reverse voltage, and 100 A non-repetitive surge current (10 ms), enabling replacement of bridge diodes in high-efficiency server and telecom power supplies.

For engineers reviewing the STIL08-T5 datasheet, STIL08-T5 pinout, STIL08-T5 application, or STIL08-T5 equivalent, this device is selected for its instantaneous response after AC line dropout, dV/dt immunity >1000 V/µs at 125°C, low 20 mA trigger current, integrated driver, and suitability in space-constrained high-power-density designs requiring reliable inrush control and surge resilience per IEC61000-4-5.

Technical Context

The STIL08-T5 operates as a dual unidirectional switch connected in parallel with the AC input bridge and external inrush resistor. During startup, internal switches remain open to route inrush current through the bridge and resistor; at steady state, auxiliary supply powers the integrated driver to close both switches, bypassing bridge diodes and reducing conduction losses.

In PFC boost configurations, the device enables automatic reactivation after AC brownout: when line recovers, switches stay open until bulk capacitor recharges via the inrush resistor, then close once PFC controller resumes operation-ensuring controlled re-energization without secondary surge.

Key Specifications

Pinout & Package

Packaged in Pentawatt (standard variant, not HV2), the STIL08-T5 uses a 5-terminal through-hole package with isolated tab for thermal and electrical grounding. The tab is electrically connected to the OUT terminal and must be mounted to a heatsink with 0.8 Nm torque.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar inrush current limitation applications.

Compared with STIL06-T5, the STIL08-T5 provides 33% higher current rating and 43% higher surge capability, enabling single-part scalability across 600–1000 W platforms; versus P1500SCLRP, it eliminates external driver design effort but requires careful PCB layout for Pt1/Pt2 noise immunity.

Availability

STIL08-T5 is available at Aetrix Electronics and suitable for server power supplies, telecom rectifiers, and high-end TV displays requiring stable component supply, long-term lifecycle support, and RoHS-compliant ECOPACK® packaging.

Supply support for STIL08-T5 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 analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

The STIL series belongs to ST's Application-Specific Devices (ASD) portfolio, engineered specifically to replace discrete inrush-limiting circuits in off-line AC-DC converters-prioritizing integration, surge resilience, and seamless PFC interoperability.

FAQ

What is the recommended heatsink interface for STIL08-T5?

The STIL08-T5 tab is electrically connected to the OUT terminal and must be mounted to a heatsink using thermal interface material and 0.8 Nm torque. A minimum heatsink thermal resistance of 1.5 °C/W is required to maintain Tj ≤ 150°C at 8 A continuous load with 25°C ambient. Mechanical isolation is unnecessary unless system ground topology demands it.

Can STIL08-T5 operate without a PFC controller?

Yes-STIL08-T5 can function in non-PFC applications such as basic inrush limiting for linear supplies or transformer-fed systems. However, its integrated driver requires ≥12 V DC at Pt1/Pt2, so an auxiliary supply must be provided externally. Without PFC feedback, the device remains latched ON after initial turn-on and does not provide power-fail reactivation.

How does STIL08-T5 handle asymmetric AC line faults?

The STIL08-T5's dual independent switches allow asymmetric fault tolerance: if only L or N experiences overvoltage, the corresponding switch blocks conduction while the other remains functional. Its 800 V VROUT rating and 1000 V/µs dV/dt immunity ensure survival during line-to-ground surges up to ±4 kV per IEC61000-4-5, provided external differential-mode chokes are used per AN1600 guidelines.

Is STIL08-T5 pin-compatible with earlier STIL variants?

Yes-STIL08-T5 shares identical Pentawatt footprint, pinout (L–Pt1–OUT–Pt2–N), and mechanical dimensions with STIL04-T5 and STIL06-T5. No PCB redesign is needed when upgrading; however, thermal management must be verified due to higher 8 A current and 100 A surge rating, which increase power dissipation by up to 40% versus STIL06-T5.