Diodes Incorporated AH2984-YG-13

Overview

AH2984-YG-13 from Diodes Incorporated is a two-phase Hall-effect smart fan motor controller IC integrating a Hall sensor, dynamic offset correction, and dual complementary open-drain output drivers with internal Zener protection. It operates from 2.5V to 15V, delivers up to 500mA average output current, and features rotor lock detection with automatic restart and over-temperature shutdown-designed specifically for two-coil BLDC cooling fans in low-voltage embedded thermal management systems.

For engineers reviewing the AH2984-YG-13 datasheet, AH2984-YG-13 pinout, AH2984-YG-13 application, or AH2984-YG-13 equivalent, key selection criteria include start-up voltage margin, integrated reverse voltage protection at VDD, Rotor Lock Protection timing (Ton = 0.25s, Toff = 3.25s), and package-specific thermal resistance (θJA = 168°C/W for SOT89-5).

Technical Context

The AH2984-YG-13 implements a closed-loop commutation control architecture using an on-chip Hall plate and amplifier to sense rotor position, feeding logic that drives complementary DO/DOB outputs with phase-shifted timing. Its lock-detection circuit monitors back-EMF absence and initiates shutdown after 0.25s of stalled condition, then attempts auto-restart after 3.25s off-time.

Thermal protection activates at +150°C junction temperature, and the device includes an internal reverse-blocking diode at VDD plus Zener clamps (24–42V) on both outputs-enabling direct connection to inductive fan coils without external flyback components in many designs.

Key Specifications

Pinout & Package

The AH2984-YG-13 is packaged in SOT89-5, featuring an exposed thermal pad for enhanced heat dissipation. Pin 5 is NC (no connection); all other pins are electrically active and thermally coupled to the die via internal routing.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar two-phase BLDC fan controller applications.

Compared with A3983SLDTR-T and NCP5425DR2G, the AH2984-YG-13 uniquely integrates Hall sensing, rotor lock auto-restart, and Zener-protected outputs in a single SOT89-5 package-reducing component count by 4–6 parts while enabling autonomous stall recovery in space-constrained thermal subsystems.

Availability

AH2984-YG-13 is available at Aetrix Electronics and suitable for server rack cooling fans, industrial PLC fan modules, and medical diagnostic equipment requiring stable component supply, long-lifecycle availability, and RoHS-compliant green packaging.

Supply support for AH2984-YG-13 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and the Americas.

The AH2984 belongs to Diodes' Smart Motor Controller product line-engineered specifically for compact, self-protecting BLDC fan and low-power motor applications in computing, industrial, and medical thermal management systems.

FAQ

What is the minimum operating voltage for reliable startup of the AH2984-YG-13?

The AH2984-YG-13 guarantees functional startup at 2.5V across the full -40°C to +105°C operating temperature range. Below 2.5V, Hall sensor sensitivity degrades and lock detection may not activate reliably-designs requiring sub-2.5V operation must validate behavior per DS31698 Rev. 4-2 Section 4.

Can the NC pin (Pin 5) on the SOT89-5 package be grounded for improved thermal performance?

No-Pin 5 is internally unconnected and must remain floating or be left un-soldered. Grounding it provides no thermal benefit and risks shorting adjacent traces; thermal performance depends solely on soldering the exposed pad (Pin 2/GND) to a minimum 25 mm² copper pour with ≥4 thermal vias.

Does the AH2984-YG-13 support PWM speed control, and if so, how is it implemented?

The AH2984-YG-13 does not accept external PWM input. Speed is controlled solely by VDD voltage level-fan RPM scales linearly with supply voltage between 2.5V and 15V. For variable-speed applications requiring precise duty-cycle control, an external DC-DC converter regulating VDD is required.

How does the internal Zener protection interact with external flyback diodes in the fan coil circuit?

The internal Zener (24–42V) clamps inductive energy during turn-off, making external flyback diodes optional. If used, external diodes must be rated ≥42V PIV and placed close to the fan terminals-not at the AH2984 pins-to avoid interfering with internal clamping action and causing latch-up.