Diodes Incorporated AH1925-HK4-7

Overview

AH1925-HK4-7 from Diodes Incorporated is an ultra-low power, omnipolar digital Hall effect switch IC in X2-DFN1410-4 package, featuring 1.4μA average supply current at 1.85V, 1.6–3.6V operating voltage, and ±25 Gauss typical operate point (BOP) with 5 Gauss hysteresis. It delivers open-drain switching for proximity detection in battery-powered IoT sensors and smart covers.

For engineers reviewing the AH1925-HK4-7 datasheet, AH1925-HK4-7 pinout, AH1925-HK4-7 application, or AH1925-HK4-7 equivalent, key selection criteria include micropower sleep current (0.36μA), chopper-stabilized temperature stability, hibernating clock architecture, and NC pin awareness in PCB layout.

Technical Context

The AH1925 employs a chopper-stabilized Hall plate with offset cancellation and integrated sleep/awake logic to achieve <±0.1mV offset drift over temperature. Its hibernating clocking system cycles between 30–80ms periods, enabling ultra-low IDD(AVG) while maintaining reliable magnetic sampling.

It uses a single open-drain output with VOL ≤ 0.2V at 0.1mA sink, operates across –40°C to +85°C, and features 8kV HBM ESD protection. The NC pin (Pin 3) must be left unconnected; the exposed thermal pad is internally unconnected and may be tied to GND for thermal relief.

Key Specifications

Pinout & Package

Package: X2-DFN1410-4 - 1.4mm × 1.0mm, 0.37mm height, low-profile DFN with exposed thermal pad (internally unconnected).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar omnipolar Hall switch applications.

Compared with AL33030QRTT and TLE4913-2K, the AH1925-HK4-7 uniquely combines sub-2μA average current, 1.6V minimum supply, and true omnipolar operation in a 1.4mm × 1.0mm footprint-making it the sole fit for long-life, space-constrained, dual-pole-sensing applications.

Availability

AH1925-HK4-7 is available at Aetrix Electronics and suitable for smart cover detection, remote utility metering, medical wearables, and IoT proximity switches requiring stable component supply and long-term lifecycle support.

Supply support for AH1925-HK4-7 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 and manufacturing operations across Asia and the Americas.

The AH1925 belongs to Diodes' Hall Effect Switch family, engineered specifically for ultra-low-power magnetic sensing in battery-operated consumer, industrial, and medical edge devices.

FAQ

What is the function of Pin 3 (NC) on the AH1925-HK4-7?

Pin 3 is designated NC (No Connection) and is internally unconnected. It must remain floating-no trace, pad, or solder should connect to this pin. Routing to GND or VDD will cause undefined behavior or damage. The exposed thermal pad beneath the package is also unconnected internally and may be tied to GND solely for thermal conduction.

Can the AH1925-HK4-7 operate reliably at 1.6V supply?

Yes-the AH1925-HK4-7 is fully specified down to 1.6V, with guaranteed BOP/BRP, IDD(AVG), and tAWAKE performance across the full –40°C to +85°C range. At 1.6V, average current remains ≤3μA and operate point stays within ±35 Gauss, making it suitable for primary lithium or alkaline cell applications.

How does the hibernating clock affect timing behavior during power-up?

Upon initial power application, the device requires two full sampling cycles (typically ~90ms total) before output state becomes valid. During this time, the output remains indeterminate. This delay is inherent to the hibernating architecture and must be accommodated in host firmware initialization sequences.

Is an external capacitor required on VDD for stable operation?

Yes-a 10nF to 100nF ceramic capacitor is recommended between VDD and GND, placed as close as possible to the device pins. This stabilizes the internal regulator during wake transitions and improves noise immunity against EFT and RF coupling, especially in high-density PCB layouts.