Diodes Incorporated AH1389-HK4-7

Overview

AH1389-HK4-7 from Diodes Incorporated is an ultra-sensitive dual-output unipolar Hall effect switch IC in X2-DFN1410-4 package, designed for pole-selective detection in battery-powered systems. It operates from 1.6V to 3.6V, draws only 4μA average supply current at 1.85V, and features independent N-pole–activated Output1 (BOPN = −25G typ.) and S-pole–activated Output2 (BOPS = +25G typ.), enabling contactless position sensing in smart covers and industrial lids.

For engineers reviewing the AH1389-HK4-7 datasheet, AH1389-HK4-7 pinout, AH1389-HK4-7 application, or AH1389-HK4-7 equivalent, key selection criteria include magnetic operate/release points (±25G/±20G), dual independent output logic (open-drain, low-active), micropower sleep mode, ESD robustness (8kV HBM), and compatibility with low-voltage microcontrollers in space-constrained PCBs.

Technical Context

The AH1389 integrates two monolithic unipolar Hall switches with chopper-stabilized amplifiers and internal offset cancellation, delivering stable switching thresholds across temperature (−40°C to +85°C) and supply voltage (1.6V–3.6V). Each output is independently controlled by orthogonal magnetic polarity: Output1 responds to negative flux density (North pole toward marking surface), Output2 to positive flux density (South pole).

Sleep/awake logic cycles the device at ~100ms period (50–100ms typical), reducing average current to 4μA at 1.85V while maintaining 50–100μs awake time for valid sampling. Internal pull-up capability eliminates external resistors, and the exposed thermal pad is electrically isolated but recommended for GND connection to enhance thermal performance.

Key Specifications

Pinout & Package

Package: X2-DFN1410-4 - 1.4mm × 1.0mm, 0.37mm height, thermally enhanced with exposed center pad (electrically isolated, recommended tied to GND).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-output unipolar Hall switch applications.

Compared with US5881 and A1120EUA-T, the AH1389-HK4-7 uniquely delivers dual independent pole detection, micropower sleep (4μA), and 1.6V operation in a 1.4mm × 1.0mm package - making it the only solution meeting simultaneous requirements for compact, battery-operated, bidirectional sensing.

Availability

AH1389-HK4-7 is available at Aetrix Electronics and suitable for smart cover detection, industrial lid position sensing, and handheld gaming console docking requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for AH1389-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, specializing in high-reliability, energy-efficient components for consumer, industrial, and computing markets.

The AH1389 belongs to Diodes' Hall-effect sensor product line, engineered specifically for ultra-low-power, dual-threshold magnetic sensing in space- and battery-constrained portable electronics.

FAQ

What is the magnetic polarity configuration for Output1 and Output2?

Output1 activates (pulls low) when a North pole magnet approaches the part marking surface, corresponding to negative magnetic flux density (BOPN = −25G typ.). Output2 activates (pulls low) when a South pole magnet approaches the same surface, corresponding to positive flux density (BOPS = +25G typ.). This polarity-specific behavior enables unambiguous directional detection without external logic.

Can the AH1389-HK4-7 operate directly from a single alkaline or lithium coin cell?

Yes - its 1.6V to 3.6V operating range supports direct connection to common primary cells: alkaline (1.5V nominal, ~1.6V fresh), lithium coin cells (3V nominal), and partially discharged Li-ion (down to 3.0V). The 4μA average current at 1.85V allows multi-year operation in always-on cover-detect applications powered by CR2032 batteries.

Is the exposed thermal pad electrically connected internally?

No - the center exposed pad in the X2-DFN1410-4 package is electrically isolated from all internal circuitry. Diodes Incorporated recommends connecting it to GND on the PCB to improve thermal dissipation and mechanical stability, but it may be left floating if thermal constraints permit. No internal bond wire connects to the pad.

How does the sleep/awake timing affect system responsiveness?

The AH1389 cycles between sleep (2.5μA) and awake (2.1mA) states every ~100ms, with a 50–100μs awake window for magnetic sampling. This yields a worst-case latency of ~100ms for state change detection. For faster response, the device must be held in awake mode via continuous VDD bias - increasing current to 2.1mA - which is supported but negates micropower advantage.