STMicroelectronics STEVAL-ISA158V1

Overview

STEVAL-ISA158V1 from STMicroelectronics is an evaluation board built around the A6986 synchronous step-down switching regulator, delivering 2 A output at up to 38 V input. It supports low-consumption mode (30 µA IQ) and low-noise mode, features adjustable switching frequency (250 kHz–2 MHz), output voltage supervision, and thermal shutdown. It is validated for automotive body electronics and infotainment power rails.

For engineers reviewing the STEVAL-ISA158V1 datasheet, STEVAL-ISA158V1 pinout, STEVAL-ISA158V1 application, or STEVAL-ISA158V1 equivalent, key selection considerations include input voltage range (4–38 V), quiescent current in LCM (30 µA), synchronization capability, soft-start adjustability, and integrated overvoltage/thermal protection for battery-powered automotive systems.

Technical Context

The board implements the A6986 IC in peak current mode control architecture with internal high-side (R_DS(on) = 180 mΩ) and low-side (R_DS(on) = 150 mΩ) MOSFETs. It supports output voltage adjustment from 0.85 V to VIN via external resistor divider on FB pin and includes embedded voltage supervisor and sequencing control.

Synchronization input (SYNCH pin) enables clock alignment with external sources; adjustable soft-start (SS/INH pin) prevents inrush current; and shutdown current is 5 µA. The design uses a 10 µH power inductor (L1), 47 µF output capacitor (C9), and 1 µF input capacitor (C2) optimized for stable 3.3 V or adjustable rail generation.

Key Specifications

Availability

STEVAL-ISA158V1 is available at Aetrix Electronics and suitable for automotive body control units, infotainment power supplies, telematics modules, and ADAS domain controllers requiring stable component supply and rapid prototyping validation.

Supply support for STEVAL-ISA158V1 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 analog, MCU, power, and sensor solutions for automotive, industrial, and consumer markets.

The STEVAL-ISA158V1 belongs to ST's ST EVAL series of application-specific evaluation boards, developed to accelerate validation of power management ICs like the A6986 in real-world automotive electrical environments.

FAQ

What input voltage range does the STEVAL-ISA158V1 support?

The board accepts 4 V to 38 V DC input, covering full automotive battery operating conditions - including engine cranking (down to ~4.5 V) and load-dump transients (up to 38 V). Input filtering uses a 4.7 µF ceramic capacitor (C14/C15) and ferrite bead (L3) to suppress high-frequency noise before the A6986 VIN pin.

How is output voltage adjusted on this evaluation board?

Output voltage is set via the FB pin using an external resistor divider. Default configuration yields 3.3 V, but R7 (180 kΩ) and R8 (130 kΩ) form the feedback network; replacing either resistor adjusts V_OUT across 0.85 V to VIN. The A6986's internal 0.6 V reference enables precise regulation independent of temperature or load.

Does the board support synchronization with external clock sources?

Yes - the SYNCH pin (U1 Pin 4) accepts external TTL/CMOS clock signals from 250 kHz to 2 MHz. When driven, the A6986 locks its internal oscillator to the external frequency, enabling EMI reduction through fixed-frequency operation and avoiding beat frequencies in multi-regulator systems.

What protection mechanisms are implemented on the STEVAL-ISA158V1?

The board inherits all A6986 protections: overvoltage lockout (OVP) triggered at ~110% V_OUT, thermal shutdown at 150 °C junction temperature, cycle-by-cycle current limiting, and undervoltage lockout (UVLO) on V_CC. No additional discrete protection components are required - these functions are fully integrated into the A6986 die.