STMicroelectronics STEVAL-ISA148V1

Overview

STEVAL-ISA148V1 from STMicroelectronics is an evaluation board for the L6563H high-voltage start-up transition-mode PFC controller, designed to demonstrate 100 W wide-range mains operation with EN61000-3-2 and JEITA-MITI compliance. It integrates a 700 V HVS pin, tracking boost function, bidirectional 1/V² voltage feedforward, remote ON/OFF control, and latched OVP/FFP protection - enabling rapid validation of PFC pre-regulator designs in AC-DC adapters and LED drivers.

For engineers reviewing the STEVAL-ISA148V1 datasheet, STEVAL-ISA148V1 application notes, STEVAL-ISA148V1 schematic, or STEVAL-ISA148V1 bill of materials, this board provides verified reference design implementation, THD-optimized current shaping, real-world brownout and inductor saturation handling, and interoperability with cascaded PWM controllers like L6599A.

Technical Context

The board implements the L6563H in continuous conduction mode (CCM)-compatible transition-mode (TM) PFC topology, using fixed-off-time control with zero-current detection (ZCD) on pin 13. Its analog front-end includes a precision 1% internal voltage reference (2.5 V), dual-path voltage feedforward (pins 3 & 5), and active tracking boost via TBO (pin 6) to dynamically scale output voltage with input RMS.

Protection architecture is fully realized: PFC_OK (pin 7) enables latched shutdown on feedback loop disconnection; PWM_LATCH (pin 8) asserts high during fault to disable downstream PWM controllers; HVS (pin 9) sustains 700 V DC with ≤100 µA start-up current; and CS (pin 4) delivers dual-threshold current sensing (0.3 V turn-off, 1.7 V saturation detection).

Key Specifications

Availability

STEVAL-ISA148V1 is available at Aetrix Electronics and suitable for AC-DC adapter development, LED driver qualification, and energy-standard compliance testing requiring stable component supply and production-ready reference design validation.

Supply support for STEVAL-ISA148V1 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, Switzerland, delivering silicon solutions for automotive, industrial, power, and analog applications with emphasis on energy efficiency and system integration.

This evaluation board belongs to ST's Power Management & Analog Solutions product line, engineered to accelerate time-to-compliance for high-efficiency AC-DC power supplies targeting IEC61000-3-2, Energy Star, and Blue Angel certification requirements.

FAQ

What is the primary purpose of STEVAL-ISA148V1?

STEVAL-ISA148V1 is a fully assembled and tested evaluation board that demonstrates the L6563H PFC controller in a 100 W transition-mode boost configuration. It validates key features including wide-range mains operation (85–265 V_AC), EN61000-3-2 Class D compliance, THD optimization via 1/V² feedforward, and robust protection schemes such as latched OVP and feedback failure detection - serving as a hardware reference for production-level PFC pre-regulator design.

Can STEVAL-ISA148V1 be used with other ST controllers like L6599A?

Yes - the board includes interface signals (PFC_OK, PWM_LATCH, PWM_STOP, RUN) explicitly designed for seamless integration with ST's resonant LLC controllers such as L6599A. Figure 46–49 in the L6563H datasheet detail circuitry for burst-mode coordination, master-slave sequencing, and fault propagation between the PFC and downstream DC-DC stages, all implemented and verified on this board.

Does STEVAL-ISA148V1 support tracking boost functionality?

Yes - the board implements the L6563H's tracking boost feature using the TBO pin (6) and associated resistor network. As shown in Figure 44 of the datasheet, output voltage scales linearly with input RMS voltage (e.g., 380 V_DC at 230 V_AC, 280 V_DC at 100 V_AC), reducing conduction losses at low line and improving light-load efficiency without compromising regulation accuracy.

How is safety isolation maintained on STEVAL-ISA148V1?

Safety isolation is achieved through reinforced creepage/clearance spacing (>8 mm between primary and secondary), dedicated NC pin (10) for PCB clearance, galvanically isolated feedback path using TL431 and optocoupler, and physical separation of high-voltage (HVS, CS, MULT) and low-voltage (COMP, INV, GND) sections. All layout practices comply with IEC62368-1 and EN60950-1 requirements for Class II equipment.