STMicroelectronics STEVAL-ISB007V1

Overview

STEVAL-ISB007V1 from STMicroelectronics is a low-cost demonstration board for Li-Ion/Li-Polymer battery charging, built around the L6924U standalone charger IC and ST7260 microcontroller. It supports dual power modes (USB 5 V and external DC adapter), delivers USB-compliant high-power charging current (up to 500 mA), features LED status indicators, and includes ICC interface for microcontroller programming.

For engineers reviewing the STEVAL-ISB007V1 datasheet, STEVAL-ISB007V1 pinout, STEVAL-ISB007V1 application, or STEVAL-ISB007V1 equivalent, this board serves as a validated reference design for USB-powered portable battery charging systems requiring compliance with USB bus-powered device specifications and flexible AC/DC input selection.

Technical Context

The board implements a complete, self-contained Li-ion charging solution where the L6924U handles constant-current/constant-voltage (CC/CV) regulation, thermal foldback via NTC sensing, and end-of-charge detection - all without firmware. In USB mode, the ST7260 performs USB enumeration, controls the L6924's SD (shutdown) pin, and monitors VBUS to enforce USB power budget limits.

When powered by an external DC adapter, the L6924U operates autonomously: its MODE pin is hardwired, SD is tied high, and ISEL/VPRE configuration resistors set charge current (500 mA) and pre-charge voltage (3.0 V). The board integrates discrete protection (STPS1L30U Schottky diodes), ESD suppression (USBLC6-2SC6), and dual-input voltage monitoring (VBUS_CHECK, ADPT_CHECK).

Key Specifications

Availability

STEVAL-ISB007V1 is available at Aetrix Electronics and suitable for USB-powered portable medical devices, handheld test instruments, rechargeable IoT edge nodes, and consumer electronics development requiring stable component supply and proven Li-ion charging reference implementation.

Supply support for STEVAL-ISB007V1 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 sensors for industrial, automotive, and consumer applications.

The STEVAL-ISB007V1 belongs to ST's ST evaluation board product line, engineered to accelerate prototyping of battery-powered USB-peripheral systems with certified compliance to USB power delivery constraints and safe Li-ion charging behavior.

FAQ

What power sources does STEVAL-ISB007V1 support?

The board accepts two independent inputs: 5 V from a standard USB port (with full USB enumeration and current limiting enforced by the ST7260), or an external DC adapter (4.5–12 V) applied to the general-purpose adaptor socket. In adapter mode, the L6924U operates independently-no microcontroller involvement is required for charging control or safety functions.

How is charge current configured on this board?

Charge current is fixed at 500 mA and set by the resistor divider on the L6924U's ISEL pin (R20 = 14 kΩ, R10 = 3.5 kΩ). This configuration enables precise current programming without firmware or external DAC. The value corresponds directly to the L6924U's internal current-sense amplifier gain and reference voltage per its datasheet transfer function.

Does STEVAL-ISB007V1 support battery temperature monitoring?

Yes-it includes a dedicated NTC thermistor input circuit connected to the L6924U's TH pin. The board provides solder pads (J11) for attaching a standard 10 kΩ NTC thermistor. When active, the L6924U reduces charge current or halts charging if battery temperature exceeds programmed thresholds, implementing JEITA-compliant thermal regulation.

Can the ST7260 firmware be reprogrammed?

Yes-the board provides an ICC (In-Circuit Communication) connector (J2) compatible with ST's standard ICC debug interface. This allows full read/write access to the ST7260's Flash memory and registers using STVD or STVP tools, enabling custom USB descriptor updates, SD pin timing adjustments, or VBUS monitoring logic modifications.