STMicroelectronics STEVAL-ISA193V1

Overview

STEVAL-ISA193V1 from STMicroelectronics is a 15 W, 5 V/3 A USB adapter evaluation board based on the STCH02 quasi-resonant flyback controller with primary-side constant current (CC) sensing. It delivers regulated output across 90–264 VAC input, achieves <10 mW no-load power at 230 VAC, meets EuCoC Rev. 5 Tier 2 and DOE EPS efficiency standards, and features EN55022 Class-B EMI compliance in a 44 × 35 × 15 mm form factor.

For engineers reviewing the STEVAL-ISA193V1 datasheet, STEVAL-ISA193V1 pinout, STEVAL-ISA193V1 application, or STEVAL-ISA193V1 equivalent, this board enables rapid validation of CC/CV USB charging designs using STCH02's integrated 650 V HV startup cell, burst-mode control, and primary-sensing feedback architecture.

Technical Context

The board implements a quasi-resonant flyback topology with primary-side regulation, eliminating optocoupler dependency for voltage and current feedback. STCH02 provides built-in 650 V HV startup, ultra-low quiescent current, and adaptive burst-mode operation to sustain <10 mW standby consumption.

Output regulation combines constant voltage (CV) below 5 V and constant current (CC) above 5 V threshold, with CC accuracy maintained across line and load variations via primary-sensed current waveform analysis - no secondary shunt or sense resistor required.

Key Specifications

Availability

STEVAL-ISA193V1 is available at Aetrix Electronics and suitable for USB charging reference design validation, low-power AC/DC adapter qualification, and energy-efficient offline SMPS development requiring stable component supply and documented performance benchmarks.

Supply support for STEVAL-ISA193V1 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, analog devices, and silicon solutions for industrial, automotive, and consumer applications.

This board belongs to ST's STEVAL (ST Evaluation) series - purpose-built reference platforms that demonstrate real-world implementation of ST's power controllers (e.g., STCH02) for fast, compliant, and layout-optimized AC/DC converter design.

FAQ

What is the primary control architecture used on STEVAL-ISA193V1?

The board uses quasi-resonant flyback control with primary-side constant voltage and constant current regulation, implemented by the STCH02 controller. It eliminates optocouplers and secondary-side sensing components by reconstructing output voltage and current from primary winding signals, reducing bill-of-materials and improving reliability.

Does STEVAL-ISA193V1 support USB Battery Charging (BC) 1.2 or USB PD?

No - STEVAL-ISA193V1 delivers fixed 5 V output only and does not implement USB BC 1.2 enumeration or USB Power Delivery protocol negotiation. It is a basic CC/CV USB adapter reference design, not a smart charging solution with data-line signaling or variable voltage profiles.

Can the output current limit be adjusted on this board?

Yes - the 3 A constant current threshold is set by R7 (0.47 Ω) in series with the primary MOSFET source. Adjusting this resistor value changes the peak current detection level, enabling scalable CC programming between ~1.5 A and 3.5 A while maintaining stability under STCH02's internal compensation limits.

Is a transformer design file or magnetic specification included with the board?

Yes - the official STEVAL-ISA193V1 datasheet (DocID029594) includes full transformer specifications: EE16 core, 470 µH primary inductance, 1:10 turns ratio, and detailed winding configuration. No separate magnetic design package is shipped, but all parameters are fully documented for replication or customization.