STMicroelectronics Introduces Fast-Starting Load Switch for Safety Systems

By Tiera Oliver

Associate Editor

Embedded Computing Design

August 29, 2022


STMicroelectronics Introduces Fast-Starting Load Switch for Safety Systems

STMicroelectronics has introduced the IPS1025HF fast-starting high-side power switch for use in safety systems that require minimal power-on delay time.

The IPS1025HF is designed to respond to turn-on and turn-off signals in less than 60µs, while considering the Vcc power-on and off, enabling protective systems to ensure a specified safety-integrity level (SIL). Featuring a 8.65V to 60V input-voltage range and tolerable at up to 65V on the input pin, the compact devices are thus able to withstand harsh industrial operating conditions. Applications include power control for programmable logic controllers (PLCs), vending machines, factory-automation I/O peripherals, and computer numerical control (CNC) machines.

The IPS1025HF has two programmable current-limit settings that allow the user to program a higher current limitation value at power switch activation. This enhances flexibility for driving loads such as bulb lamps, motors, and capacitive loads that demand high initial peak current.

The output stage is a N-channel Power MOSFET with a typical Rds(on) of 12.5mOhm at ambient temperature, ensuring high energy efficiency and low thermal dissipation. The MOSFET is internally limited at 2.5A minimum output current and has single-pulse avalanche energy up to 14J, which boosts reliability for handling inductive loads. There is also an integrated active clamp for fast demagnetization.

The switch includes protection against undervoltage, overvoltage, overload, short circuit, ground disconnection, and Vcc disconnection. On-chip diagnostics include individual signaling of output overload and junction overtemperature and there is an extra thermal sensor to detect excessive case temperature. The device is designed to meet IEC 61000-4-2 ESD, IEC 61000-4-4, and IEC 61000-4-5 specifications for ESD, fast-transient, and surge immunity.

For fast evaluation, the X-NUCLEO-OUT15A1 expansion board contains an IPS1025HF with associated circuitry ready to connect to STM32 Nucleo development boards. A demonstration firmware pack, STSW-OUT15F4, and industrial-automation system design GUI, STSW-IFAPGUI, are also available and enable users to realize an entire industrial-automation environment on the desktop.

The IPS1025HF is in production now, available in both PowerSSO-24 and QFN48L packages, priced from $3.51 for orders of 1000 units.

For more information, visit

Tiera Oliver, Associate Editor for Embedded Computing Design, is responsible for web content edits, product news, and constructing stories. She also assists with newsletter updates as well as contributing and editing content for ECD podcasts and the ECD YouTube channel. Before working at ECD, Tiera graduated from Northern Arizona University where she received her B.S. in journalism and political science and worked as a news reporter for the university’s student led newspaper, The Lumberjack.

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