STMicroelectronics EVALA6902D

Overview

EVALA6902D from STMicroelectronics is an automotive-grade evaluation board for the A6902D step-down switching regulator with adjustable current limit. It implements a voltage-mode DC-DC converter featuring an integrated P-channel DMOS (R_DS(on) = 250 mΩ), 250 kHz fixed-frequency operation, ±5% current limit accuracy via external sense resistor, and dual-loop control supporting both constant-voltage (1.235 V to 35 V) and constant-current modes - used in LED drivers and NiMH/NiCd battery chargers.

For engineers reviewing the EVALA6902D datasheet, EVALA6902D pinout, EVALA6902D application, or EVALA6902D equivalent, this board enables rapid validation of A6902D's automotive-grade performance under real-world load transients, thermal stress, and feedback disconnection protection - critical for functional safety-critical power designs requiring AEC-Q100 compliance and zero-load burst-mode operation.

Technical Context

The EVALA6902D board hosts the A6902D IC in SO-8 package and provides full access to all eight pins (OUT, CS+, CS−, COMP, FB, VREF, GND, VCC) with test points, jumper-selectable feedback dividers, and configurable current-sense resistor pads. It supports input voltages from 8 V to 36 V and delivers up to 1 A DC output current with precise 3.3 V reference (±2%) and internal thermal shutdown at 150 °C ±10 °C.

It validates the A6902D's dual error amplifier architecture: one transconductance amplifier (2.3 mS, 50–58 dB gain) for voltage regulation referenced to 1.235 V, and another (1.9 mS, 60 dB gain) for current regulation sensing 100 mV across R_SENSE, sharing a single COMP compensation network for stable loop closure across both operating modes.

Key Specifications

Availability

EVALA6902D is available at Aetrix Electronics and suitable for automotive infotainment power supplies, LED headlamp drivers, NiMH battery charging circuits, and industrial DC-DC converter prototyping requiring stable component supply and AEC-Q100-compliant reference validation.

Supply support for EVALA6902D 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, designing and manufacturing microcontrollers, power management ICs, analog chips, and automotive-grade components for industrial, automotive, and consumer applications.

The A6902D product line targets automotive power conversion with integrated current limiting and AEC-Q100 qualification - engineered specifically for robust, compact, and thermally resilient step-down regulators in battery-fed systems where reliability under wide-input-voltage and zero-load conditions is mandatory.

FAQ

What is the purpose of the EVALA6902D evaluation board?

The EVALA6902D is a fully assembled, tested reference design board that demonstrates and validates the A6902D step-down regulator's dual constant-voltage and constant-current operation. It includes layout-optimized power stages, accessible test points for all eight pins, configurable feedback and current-sense networks, and supports input ranges from 8 V to 36 V - enabling immediate functional verification without custom PCB development.

Does EVALA6902D support both voltage and current regulation modes?

Yes - the board enables both modes via its on-board configuration options. Voltage regulation uses the FB pin with an external resistive divider to set output from 1.235 V to 35 V; current regulation uses CS+ and CS− pins with a precision sense resistor to deliver adjustable constant current (e.g., for LED drivers or battery charging), with ±5% accuracy confirmed across temperature.

How does EVALA6902D handle thermal and overcurrent protection?

The board directly exposes the A6902D's embedded protections: thermal shutdown triggers at 150 °C ±10 °C with ~20 °C hysteresis, and overcurrent is managed via two independent mechanisms - a precise average-current loop (via CS pins) and fast pulse-by-pulse limiting (with 270 ns blanking time). Frequency foldback reduces switching frequency to 1/3 nominal (≈83 kHz) under severe overload.

Can EVALA6902D operate with no load connected?

Yes - thanks to the A6902D's high-side P-channel MOSFET architecture, no bootstrap capacitor is needed, allowing true zero-load operation. Under no-load conditions, the device enters burst mode with random repetition rate, maintaining regulation while minimizing quiescent current (I_q = 2.7–5 mA), critical for always-on automotive subsystems.