STMicroelectronics STEVAL-ISA106V1

Overview

STEVAL-ISA106V1 from STMicroelectronics is a demonstration board for the L5973AD 1.5 A step-down monolithic switching regulator, supporting adjustable output voltages from 1.235 V to 35 V, input voltage range 4 V to 36 V, fixed 500 kHz switching frequency, and featuring synchronization, inhibit, short-circuit, and thermal shutdown protection. It serves as an evaluation platform for DC/DC power conversion in industrial and embedded power supply designs.

For engineers reviewing the STEVAL-ISA106V1 datasheet, STEVAL-ISA106V1 schematic, STEVAL-ISA106V1 application circuit, or STEVAL-ISA106V1 alternative evaluation boards, this page provides verified pinout mapping (via L5973AD integration), functional validation context, output adjustability range, thermal protection behavior, and board-level design constraints including input capacitor voltage rating limits.

Technical Context

The STEVAL-ISA106V1 implements the L5973AD in a non-isolated buck topology with internal 500 kHz oscillator, enabling compact high-efficiency regulation across wide input (4–36 V) and output (1.235–35 V) ranges. Its inhibit pin allows external enable/disable control, while the sync pin supports external clock synchronization to avoid beat frequencies in multi-regulator systems.

Board-level protections include cycle-by-cycle current limiting, automatic recovery from short-circuit events, and thermal shutdown activation at junction temperature ≥165 °C. The output voltage is set via an external resistor divider connected to the FB pin of the L5973AD, with feedback reference voltage of 1.235 V.

Key Specifications

Availability

STEVAL-ISA106V1 is available at Aetrix Electronics and suitable for industrial power supply validation, embedded system DC/DC prototyping, and automotive auxiliary rail evaluation requiring stable component supply and documented reference design implementation.

Supply support for STEVAL-ISA106V1 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, designing and manufacturing microcontrollers, analog ICs, power management devices, and silicon solutions for industrial, automotive, and consumer applications.

The STEVAL-ISA106V1 belongs to ST's STEVAL demonstration board family, engineered to accelerate evaluation and adoption of its power management ICs-specifically targeting rapid validation of buck regulator performance, layout best practices, and protection feature behavior under real load conditions.

FAQ

What is the maximum recommended input voltage for STEVAL-ISA106V1?

The board uses a 35 V-rated input capacitor, limiting the absolute maximum safe input voltage to 35 V DC. Operation above 36 V violates the L5973AD's absolute maximum rating and risks permanent damage to both IC and passive components. Input voltage must remain within 4–36 V per the L5973AD datasheet and board design constraints.

Can the output voltage be set below 1.235 V?

No. The L5973AD's internal feedback reference voltage is fixed at 1.235 V ±1.5%, and the STEVAL-ISA106V1 schematic implements standard resistive divider feedback without offset injection or external reference modification. Output voltages lower than 1.235 V are not supported by this board's configuration.

Does STEVAL-ISA106V1 support external clock synchronization?

Yes. The board exposes the L5973AD's SYNC pin (pin 5), allowing connection to an external 500 kHz ±10% clock source. When driven, the internal oscillator is disabled and switching follows the external signal, enabling noise-sensitive multi-rail systems to avoid beat frequencies and EMI peaks.

Is thermal shutdown automatically recoverable?

Yes. The L5973AD implements latch-off thermal shutdown: when junction temperature exceeds ~165 °C, the device halts switching and holds output low until temperature drops below ~145 °C hysteresis, then resumes normal operation without manual reset. This behavior is preserved on STEVAL-ISA106V1 with no additional intervention required.