Intelligent load management solution based on STMicroelectronics IPS1025HF, STM32 Nucleo

Hedy · Dasenic Jan 14,2025 27

Industrial digital input/output ICs are used in electronic control systems in our daily lives, usually in smart factories and home and building automation, and are also widely used in urban and transportation infrastructure control.

Actuators in automation enable control systems to perform electrical and electromechanical actions that receive information and data from smart sensors. Typically an actuator can be viewed as a resistive electrical load with specific characteristics and parameters (resistance, capacitance, inductance).

Therefore, industrial digital output modules need to work with any actuator installed in the field, regardless of their specific electrical parameters!

To address this technical challenge and provide greater flexibility to design engineers, ST has developed a new generation of intelligent power switches (IPS) that implement a unique active current limit control feature called Intelligent Load Management.

The IPS1025HF is a fast-start high-side power switch targeting safety systems that require extremely short power-on delay times. Taking into account the Vcc power supply on and off conditions, in order to ensure that the safety protection system can reach the specified safety integrity level (SIL), the on and off response time of IPS1025HF is still less than 60µs. This device supports a wide-voltage power supply from 8.65V to 60V, and the input pin's maximum withstand voltage is up to 65V, making it capable of withstanding severe operating conditions in industrial applications. Target applications include Programmable Logic Controllers (PLCs), vending machines, factory automation I/O peripherals, and Computer Numerical Controls (CNCs).

IPS1025HF is similar to the single-channel and dual-channel products in STMicroelectronics’ smart power switch series. It has two programmable current limit settings, allowing users to set a high current limit value when the power switch is activated, thereby increasing the load. Flexibility to drive, for example, applications such as light bulbs, motors and capacitive loads that require high initial peak current. The output stage is an N-channel power MOSFET with a typical on-resistance Rds(on) of 12.5mOhm at ambient temperature, ensuring high switching efficiency and low heat dissipation. The MOSFET internally limits the minimum output current to 2.5A, and the maximum single pulse burst energy is 14J, which can improve the reliability of handling inductive loads. The new product also internally integrates an active clamping circuit with fast demagnetization function.

The switch's safety features include undervoltage, overvoltage, overload, short circuit, ground disconnect protection and Vcc disconnect protection. On-chip diagnostic pins include independent output overload and junction overheating signals, and a thermal sensor is added to monitor package temperature. These switches comply with the ESD, fast transient and surge immunity specifications of IEC 61000-4-2 ESD, IEC 61000-4-4 and IEC 61000-4-5. In order to facilitate developers to quickly evaluate the switching function, the X-NUCLEO-OUT15A1 solution board integrates IPS1025HF and related circuits and can be directly used with the STM32 Nucleo development board. It includes the STSW-OUT15F4 firmware package and STSW-IFAPGUI industrial automation system design graphical user interface software, which can help users create a complete industrial automation environment on their computer desktop. IPS1025HF is now in mass production, available in PowerSSO-24 and QFN48L packages.

The other is the STEVAL-IFP040V1 industrial digital output solution, which provides a powerful and flexible IPS1025HF single high-side smart power solid-state relay for use in digital output modules connected to 2.5 A industrial loads. STEVAL-IFP040V1 interfaces with microcontrollers on the STM32 Nucleo via universal input pins and a 5 kV optocoupler driven by the Arduino® UNO R3 connector. The solution board can be connected to the NUCLEO-F401RE or NUCLEO-G431RB development board.