Asahi Kasei Microdevices/AKM HQ8220

Overview

HQ8220 from Asahi Kasei Microdevices (AKM) is a 4-element InAs quantum well Hall-effect position sensor IC designed for non-contact X-Y magnetic position detection. It delivers 95 mV typical output Hall voltage at B = 50 mT and VC = 3 V, with ±6% relative output voltage ratio, 850 Ω typical input resistance, and operates across –40 °C to +125 °C ambient temperature for automotive throttle and pedal sensing.

For engineers reviewing the HQ8220 datasheet, HQ8220 pinout, HQ8220 application, or HQ8220 equivalent, key selection criteria include its four differential Hall element outputs (HE1–HE4), temperature-stable offset voltage (±0.2 mV/°C), dual-axis linear position resolution, and compatibility with low-noise analog signal conditioning stages in safety-critical motion feedback systems.

Technical Context

The HQ8220 integrates four spatially arranged InAs quantum well Hall elements in a single die to enable simultaneous X- and Y-axis magnetic field vector measurement. Its output voltage ratio (VHr) and input resistance ratio (Rinr) are characterized across temperature to support ratiometric position decoding without external reference.

Each Hall element pair (e.g., HE1/HE4 for Y, HE2/HE3 for X) provides complementary differential outputs, enabling center-position detection via voltage comparison. The device requires constant-current or constant-voltage biasing (VC = 3 V, IC = 5 mA) and exhibits linear VH vs. B response up to ±50 mT with <±0.2 mV/°C offset drift.

Key Specifications

Pinout & Package

Package: Surface-mount ceramic QFN-24 (6.20 mm × 6.20 mm × 0.95 mm, 0.65 mm pitch), moisture sensitivity level MSL3.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-axis Hall position sensing applications.

Compared with MLX90393 and A1335, the HQ8220 provides native differential analog outputs optimized for low-latency, noise-immune analog signal chains - making it preferred for real-time safety-critical feedback loops where external ADC timing and digital processing overhead must be minimized.

Availability

HQ8220 is available at Aetrix Electronics and suitable for automotive throttle position sensing, brake pedal monitoring, steering angle feedback, and industrial valve position control requiring stable component supply and long-term lifecycle assurance.

Supply support for HQ8220 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

Asahi Kasei Microdevices (AKM) is a Japanese semiconductor company specializing in analog and mixed-signal ICs, particularly high-precision magnetic sensors and audio codecs.

The HQ8220 belongs to AKM's quantum well Hall-effect sensor product line, engineered specifically for high-accuracy, contactless 2D position measurement in automotive and industrial motion control systems.

FAQ

What is the operating voltage range for the HQ8220?

The HQ8220 operates with a nominal supply voltage of 3 V applied across its differential input terminals (e.g., HE1inP/HE1inN). Absolute maximum input voltage is 6 V, and maximum input current is 9 mA. Operation outside the recommended 3 V ±10% range degrades linearity and increases offset drift. The HQ8220 does not contain an internal voltage regulator, so stable biasing is essential for repeatable performance.

How does the HQ8220 achieve X-Y position detection?

The HQ8220 achieves X-Y position detection using four physically separated InAs quantum well Hall elements arranged orthogonally. HE1 and HE4 form the Y-axis pair; HE2 and HE3 form the X-axis pair. Their differential outputs are compared externally: equal voltages indicate center position, while voltage differences quantify displacement magnitude and direction. This architecture is implemented directly in the HQ8220 die layout and requires no internal logic or processing.

Is the HQ8220 RoHS compliant and lead-free?

Yes, the HQ8220 is RoHS compliant and manufactured with lead-free terminations. Per AKM's documentation, it meets EU RoHS Directive 2011/65/EU requirements and contains no restricted substances above threshold limits. The package uses matte tin plating, and the device is qualified for standard lead-free reflow profiles (peak temperature ≤260 °C). Full compliance documentation is available upon request from Aetrix Electronics.

What is the significance of the Relative Output Voltage Ratio (±6%) specification for the HQ8220?

The ±6% Relative Output Voltage Ratio (VHr) for the HQ8220 quantifies inter-element gain matching across the four Hall sensors. It means the maximum deviation of any single element's output from the average output is ≤6%, ensuring consistent sensitivity between X and Y axes. This tight matching allows accurate centroid calculation without per-channel calibration - a critical requirement for reliable position detection in safety-critical automotive applications like electronic throttle control.

Can the HQ8220 be used in safety-critical automotive systems?

The HQ8220 is designed for automotive use and operates across –40 °C to +125 °C, but AKM explicitly states it is not authorized for safety-critical systems (e.g., airbag control, ABS, steering-by-wire) unless approved in writing by AKM's Representative Director. For throttle and pedal sensing, it may be deployed in ASIL-B architectures when combined with redundancy, diagnostics, and system-level validation - however, final qualification remains the responsibility of the end-system integrator.