STMicroelectronics STEVAL-ISA203V1

Overview

STEVAL-ISA203V1 from STMicroelectronics is a fully assembled, RoHS-compliant evaluation board implementing a 60 W (12 V/5 A) flyback DC-DC converter for 42–56 VDC telecom input rails. It integrates the PM8804 peak-current-mode PWM controller and SRK1000 adaptive synchronous rectification controller, with STL130N8F7 PowerFLAT 5x6 MOSFET on secondary side, achieving >92% peak efficiency at 200 kHz switching frequency.

For engineers reviewing the STEVAL-ISA203V1 datasheet, STEVAL-ISA203V1 pinout, STEVAL-ISA203V1 application, or STEVAL-ISA203V1 equivalent, this board serves as a validated reference design for high-efficiency 48 V telecom power conversion-enabling rapid prototyping of PoE-powered infrastructure, server auxiliary supplies, and industrial 48 V-to-12 V point-of-load stages.

Technical Context

The board implements continuous conduction mode (CCM) flyback topology with primary-side regulation via PM8804, featuring programmable oscillator (up to 1 MHz), adjustable slope compensation, dual low-side drivers (1 A sink), soft-start, soft-turn-off, and current-sense blanking. GAT1 drives the primary MOSFET; GAT2 supports active-clamp configurations.

Secondary-side synchronous rectification uses SRK1000, which senses body-diode conduction of the STL130N8F7 N-channel MOSFET (80 V, 3.0 mΩ typ.) to precisely time gate drive, minimizing conduction loss and enabling >92% measured efficiency across 42–56 V input and full 0–5 A load range.

Key Specifications

Availability

STEVAL-ISA203V1 is available at Aetrix Electronics and suitable for telecom power supply validation, PoE-powered equipment development, and 48 V server auxiliary rail design requiring stable component supply and pre-validated thermal and efficiency performance.

Supply support for STEVAL-ISA203V1 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 chips, and silicon solutions for industrial, automotive, and communications markets.

This board belongs to ST's STEVAL evaluation platform family, engineered to accelerate adoption of its power management ICs-including PM8804 and SRK1000-in high-efficiency, high-reliability telecom and server power applications.

FAQ

What input voltage range does STEVAL-ISA203V1 support?

The board accepts 42–56 VDC input, centered on nominal 48 V telecom distribution systems. This range accommodates standard -36 V to -72 V legacy telecom battery systems when referenced to ground, and aligns with IEEE 802.3bt PoE++ midspan voltage specifications. Input filtering includes DO3316H-121MLD common-mode choke and bulk capacitors.

Can STEVAL-ISA203V1 be used for active-clamp flyback designs?

Yes-the PM8804 controller on this board provides GAT2, a second low-side driver configurable for active-clamp operation. The schematic shows GAT2 routed to a P-channel MOSFET position (Q3), and the controller supports programmable dead time and slope compensation required for stable active-clamp flyback implementation at 200 kHz.

What is the role of the SRK1000 controller on this board?

SRK1000 monitors the body diode conduction of the STL130N8F7 synchronous rectifier MOSFET and triggers gate drive only during forward conduction, eliminating reverse recovery losses and improving light-load efficiency. Its adaptive sensing avoids fixed-timing errors caused by variable propagation delays or MOSFET threshold drift.

Does STEVAL-ISA203V1 include thermal measurement data?

Yes-ST's DB4096 data brief reports STL130N8F7 junction temperature of 68 °C at full 5 A load, measured under natural convection. The board uses PowerFLAT 5x6 package for low thermal resistance, and thermal imaging confirms uniform heat distribution across the MOSFET copper pad, supporting reliable 60 W operation without forced airflow.