STMicroelectronics STEVAL-ISA207V1

Overview

STEVAL-ISA207V1 from STMicroelectronics is an automotive-grade evaluation board implementing a 4.5 V to 60 V input, 3.3 V/3 A step-down DC/DC switching regulator using the A7987 controller in HTSSOP16 package; features 500 kHz fixed switching frequency, 3.5 ms soft-start, and 180° out-of-phase synchronization capability for multi-rail battery systems.

For engineers reviewing the STEVAL-ISA207V1 datasheet, STEVAL-ISA207V1 pinout, STEVAL-ISA207V1 application, or STEVAL-ISA207V1 equivalent, this board enables rapid validation of A7987-based buck converter designs in 12 V/24 V/48 V automotive power architectures with ceramic output capacitor support and auto-recovery protection.

Technical Context

The board implements the A7987 asynchronous buck regulator with integrated 61 V/3 A high-side MOSFET, supporting adjustable current limit via ILIM pin and programmable switching frequency up to 1.5 MHz through external resistor on FSW pin. It uses pulse-skipping light-load management and VBIAS switchover for efficiency optimization across 0–3 A load range.

Designed for automotive battery-powered systems, it delivers low dropout operation near VIN = VOUT (e.g., 3.3 V output at 4.5 V input), supports synchronization of two A7987 units to reduce input RMS current, and includes PGOOD monitoring, EN control, and thermal/overcurrent auto-recovery protection.

Key Specifications

Availability

STEVAL-ISA207V1 is available at Aetrix Electronics and suitable for automotive infotainment power supplies, ADAS camera module rails, and body control module (BCM) sub-regulators requiring stable component supply and fast design validation.

Supply support for STEVAL-ISA207V1 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, power ICs, sensors, and analog devices for automotive, industrial, and consumer applications.

The STEVAL-ISA207V1 belongs to ST's automotive evaluation board portfolio, developed specifically to accelerate adoption of the A7987 high-voltage buck regulator in battery-connected systems demanding robustness, efficiency, and functional safety readiness.

FAQ

Can STEVAL-ISA207V1 be used for 5 V output applications?

Yes - the board's FB pin is accessible and the output voltage is set by R7 (7.5 kΩ) and R8 (47 kΩ); replacing these resistors recalculates the divider ratio to achieve 5 V (e.g., R7 = 10 kΩ, R8 = 56.2 kΩ). The A7987 supports outputs from 0.8 V to VIN − 1.5 V.

Does STEVAL-ISA207V1 support spread-spectrum frequency modulation?

No - the A7987 does not integrate spread-spectrum modulation. Switching frequency is either internally fixed at 250 kHz or externally adjustable (250 kHz–1.5 MHz) via resistor on FSW pin, but no dithering or jitter functionality is implemented per DB3887.

What is the role of the VBIAS pin on this board?

VBIAS powers the internal gate driver and bias circuitry. When VIN > 5.5 V, the A7987 automatically switches VBIAS to internal LDO output; below that, it draws from external VBIAS supply - enabling higher efficiency in wide-input automotive transients.

Is PGOOD signal actively driven or open-drain?

PGOOD is an open-drain output - pulled low when output is within ±10% of target (3.3 V ±330 mV). External pull-up (e.g., to 3.3 V or 5 V) is required, as shown on board with R11 (2.4 kΩ) to VOUT.