Diodes Incorporated AH1815-W-7

Overview

AH1815-W-7 from Diodes Incorporated is a low-sensitivity, micropower omnipolar Hall-effect switch IC in SC59 package, designed for magnetic tamper detection in smart meters and position sensing in battery-powered consumer devices. It operates from 2.5V to 5.5V, consumes only 24µW at 3V, features open-drain output, and switches on with either north or south pole (B_op = ±255–540 G). Its chopper-stabilized architecture ensures stable operation from –40°C to +125°C.

For engineers reviewing the AH1815-W-7 datasheet, AH1815-W-7 pinout, AH1815-W-7 application, or AH1815-W-7 equivalent, key selection criteria include magnetic sensitivity range (±255–540 G), ultra-low sleep current (≤28 µA), omnidirectional pole response, and SC59 package compatibility with space-constrained PCB layouts in metering and portable electronics.

Technical Context

The AH1815-W-7 integrates dual Hall plates and chopper-stabilized amplification to cancel offset drift and suppress temperature-induced switching point variation. Its latch-based output driver delivers clean, hysteresis-controlled (≥40 G) transitions between on-state (V_{OUT_ON} ≤ 0.3 V @ 1 mA) and off-state (I_OFF < 1 µA).

It employs adaptive sleep/awake logic to achieve 24 µW average power at 3V: awake time is 75–125 µs per cycle, with period of 75–125 ms and duty cycle ≤0.1%, enabling multi-year battery life in sealed smart-meter modules and lid-detection systems.

Key Specifications

Pinout & Package

Package: SC59 - 3-pin, low-profile surface-mount package (2.8 mm × 1.6 mm × 0.95 mm), RoHS-compliant, lead-free, suitable for reflow soldering and high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with A3212LLHLT-T and US1881EUA-ABA-000-REEL, AH1815-W-7 uniquely balances low-sensitivity tamper resistance, micropower operation, and chopper-stabilized thermal robustness - making it the optimal choice for long-life, field-deployed utility metering and industrial enclosure monitoring.

Availability

AH1815-W-7 is available at Aetrix Electronics and suitable for smart meter tamper detection, appliance lid sensing, coffee machine liquid level monitoring, and tablet display lid switching requiring stable component supply, extended lifecycle support, and RoHS-compliant sourcing.

Supply support for AH1815-W-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 industrial, automotive, and consumer markets.

The AH1815 belongs to Diodes' Hall-effect sensor product line, engineered specifically for contactless position and tamper detection in battery-powered and harsh-environment applications where ultra-low power and thermal stability are critical.

FAQ

What is the magnetic polarity response of AH1815-W-7?

The AH1815-W-7 is an omnipolar Hall switch: it activates (pulls output low) when exposed to either a sufficiently strong north pole or south pole oriented toward the marked side of the SC59 package. Its operating points range from ±255 G to ±540 G, with hysteresis ≥40 G to prevent chatter. This eliminates mechanical orientation constraints during assembly in smart meters and appliance lids.

How does the chopper-stabilized architecture improve performance?

The chopper-stabilized design alternately samples and cancels offset voltage in the Hall amplifier chain, reducing temperature-induced drift to <±0.5 mV. This ensures stable B_op and B_rp values across –40°C to +125°C - critical for tamper detection reliability in outdoor utility meters where ambient temperature swings exceed 100°C.

Can AH1815-W-7 operate directly from a 3.3V MCU I/O rail?

Yes - AH1815-W-7 operates from 2.5V to 5.5V, making it fully compatible with standard 3.3V logic rails. Its open-drain output can be pulled up to 3.3V (or up to 5.5V), and its 0.3 V_ON max at 1 mA ensures clean low-level signaling into 3.3V GPIO inputs. No level-shifting circuitry is required.

What is the recommended external circuit for reliable operation?

A 10–100 nF ceramic capacitor between VDD and GND (placed within 2 mm of pins 1 and 2) is mandatory for power stabilization and RF noise immunity. A 10–100 kΩ pull-up resistor on the OUTPUT pin (pin 3) sets the logic-high level. These components ensure stable sampling, prevent false triggers, and meet the 75–125 µs awake-time specification per datasheet Figure 5.