Diodes Incorporated AH1902-Z-7

Overview

AH1902-Z-7 from Diodes Incorporated is a high-sensitivity, micropower omnipolar Hall-effect switch IC in SOT553 package, operating from 1.6V to 3.6V supply with 4.3μA average current at 1.8V. It activates on either north or south magnetic pole, delivers open-drain output (pulled low when active), and features chopper-stabilized architecture for thermal stability-used in flip-phone lid detection, smart cover sensing, and portable PC display switches.

For engineers reviewing the AH1902-Z-7 datasheet, AH1902-Z-7 pinout, AH1902-Z-7 application, or AH1902-Z-7 equivalent, key selection criteria include magnetic operate/release points (±23–47 G), ultra-low sleep current (2.5μA), hysteresis (10 G typical), -40°C to +85°C operation, and SOT553 footprint compatibility with space-constrained portable designs.

Technical Context

The AH1902-Z-7 implements a chopper-stabilized Hall sensor with integrated latch and sleep/awake logic, enabling stable switching across temperature and supply voltage variations. Its hibernating clocking system cycles between 50μs awake time and 100ms period, achieving sub-5μA average current while maintaining valid output after two cycles (~100ms).

It uses an internal pull-down and pull-up structure eliminating external resistors, and its output stage sinks up to 3mA with VOL ≤ 0.2V at 1mA load. Magnetic thresholds are specified for both poles (Bopn/Bops: ±24–47 G) and exhibit <10G hysteresis (Bhy), ensuring noise-immune position detection without false triggering.

Key Specifications

Pinout & Package

SOT553 package: 5-pin, low-profile surface-mount with exposed pad not internally connected; pin 1 (NC), pin 2 (GND), pin 3 (NC), pin 4 (VDD), pin 5 (OUTPUT); NC pins may be left floating or tied to GND for mechanical stability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AL3320EUA-7 and TLE4913-2K, the AH1902-Z-7 uniquely balances ultra-low power (4.3μA), SOT553 footprint, and robust 8kV ESD-making it optimal for consumer portable devices where size, battery life, and cost are co-primary constraints.

Availability

AH1902-Z-7 is available at Aetrix Electronics and suitable for flip phone lid detection, smart cover sensing, digital camera lens cap monitoring, and home appliance door position switching requiring stable component supply across high-volume consumer electronics production.

Supply support for AH1902-Z-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, manufacturing, and sales operations across Asia, Europe, and the Americas.

The AH1902 belongs to Diodes' Hall-effect sensor product line, engineered specifically for ultra-low-power, space-constrained portable electronics-including smartphones, tablets, wearables, and battery-operated appliances.

FAQ

What magnetic field strength is required to activate the AH1902-Z-7?

The AH1902-Z-7 activates when perpendicular magnetic flux density exceeds ±23–47 Gauss (±2.3–4.7 mT), depending on temperature and supply voltage. At 25°C and 1.8V, typical operate points are ±33 G for both poles, with 10 G hysteresis ensuring clean switching without oscillation near threshold.

Can the AH1902-Z-7 operate from a 1.5V alkaline battery?

Yes-the AH1902-Z-7 functions down to 1.6V supply, making it compatible with fresh 1.5V alkaline cells (which typically deliver 1.6V under light load). Performance remains within specification until VDD drops below 1.6V; output behavior is guaranteed across the full 1.6–3.6V range.

Is an external decoupling capacitor required for stable operation?

Yes-a 100nF ceramic capacitor is mandatory between VDD and GND, placed as close as possible to the SOT553 pins. This stabilizes the internal regulator during wake cycles and enhances RF noise immunity, as confirmed in the DS36533 functional circuit diagram and layout guidelines.

Does the SOT553 package of AH1902-Z-7 include a thermal pad?

No-the SOT553 package has no exposed thermal pad. Pins 1 and 3 are NC (no internal connection), and the package relies on PCB copper area under pins 2 (GND) and 4 (VDD) for thermal conduction. The datasheet explicitly states the center pad is absent and no thermal pad is present in this variant.