Monolithic Power Systems Inc. MAQ850GQE-AEC1-P

Overview

MAQ850GQE-AEC1-P from Monolithic Power Systems is an AEC-Q100 Grade 1 automotive magnetic angle encoder delivering 8-bit absolute angular position via PWM output, with configurable push/pull button detection using dual magnetic field thresholds (MGH/MGL), 3.3V supply, and QFN-16 (3mm×3mm) packaging - deployed in rotary knob HMI controls requiring contactless, wear-free sensing below 200rpm.

For engineers reviewing the MAQ850GQE-AEC1-P datasheet, MAQ850GQE-AEC1-P pinout, MAQ850GQE-AEC1-P application, or MAQ850GQE-AEC1-P equivalent, key selection considerations include PWM frequency stability (42–56kHz), INL accuracy (±1.1° over −40°C to +125°C), SPI-configurable zero angle and rotation direction, magnetic threshold hysteresis (6mT), and NVM-stored calibration parameters for production traceability.

Technical Context

The MAQ850GQE-AEC1-P implements SpinAxis™ phase-detection architecture: integrated Hall sensors digitize in-plane magnetic field direction without arctangent computation, feeding a time-to-digital converter that outputs raw angle at 1MHz before digital filtering. Its open-loop front-end ensures no latency under steady-state rotation.

Digital conditioning includes a programmable low-pass filter (f_CUTOFF = 90Hz) and on-chip non-volatile memory storing zero-angle offset (16-bit), magnetic high/low thresholds (3-bit each), and rotation direction (CW/CCW). SPI interface supports auto-detected Mode 0/3 up to 25MHz for register read/write, with 20ms NVM write delay enforced between frames.

Key Specifications

Pinout & Package

MAQ850GQE-AEC1-P is housed in a thermally enhanced QFN-16 (3mm × 3mm) package with exposed thermal pad (recommended to be connected to GND). Pin 1 is located at top-left corner of top view; pin numbering follows counter-clockwise sequence.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar magnetic angle encoder applications.

Compared with AS5600-DSO and TMAG5170AHQ, MAQ850GQE-AEC1-P uniquely integrates PWM output, dual magnetic flag logic, and NVM-stored calibration - enabling direct analog potentiometer replacement in automotive HMIs without additional signal conditioning or firmware overhead.

Availability

MAQ850GQE-AEC1-P is available at Aetrix Electronics and suitable for automotive climate control interfaces, white goods rotary dials, and industrial manual control panels requiring stable component supply, AEC-Q100 compliance, and long-lifecycle support.

Supply support for MAQ850GQE-AEC1-P 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

Monolithic Power Systems (MPS) designs high-performance power management and sensing ICs for automotive, industrial, and consumer applications, emphasizing integration, efficiency, and reliability.

The MagAlpha® family - including MAQ850GQE-AEC1-P - targets contactless human-machine interfaces, delivering robust magnetic angle sensing with embedded intelligence for automotive-grade manual controls.

FAQ

What is the maximum rotational speed supported by MAQ850GQE-AEC1-P?

The MAQ850GQE-AEC1-P is specified for slow-speed human-interface applications up to 200rpm. Its 850–1100kHz internal refresh rate and <4ms latency ensure accurate position tracking within this range. Operation above 200rpm may exceed mechanical mounting stability limits and degrade linearity due to dynamic field distortion, not electrical bandwidth constraints.

How is zero-angle calibration performed and stored?

Zero-angle offset is configured via 16-bit Z(15:0) parameter written to registers 0 and 1 over SPI. The value represents the complementary angle (e.g., 20° → Z = 61895). Once written, it is stored in on-chip NVM and automatically loaded at power-up, eliminating need for runtime recalibration in production systems.

Can the PWM output drive an RC low-pass filter directly to emulate a potentiometer?

Yes - the PWM output (10–90% duty cycle, ~50kHz) can be filtered with a simple RC network (e.g., 10kΩ + 100nF) to generate a ratiometric analog voltage (0.33–3.0V at 3.3V supply). Figure 17 in the datasheet shows a buffered op-amp variant for wider voltage ranges and improved load regulation.

What magnet configuration is recommended for optimal linearity?

A diametrically magnetized NdFeB cylinder (N35 grade, Ø5mm × 3mm) mounted coaxially with ≤0.5mm positional tolerance and 1.5mm air gap delivers best-in-class linearity (<0.7° INL at 25°C). Field strength must remain within 45–100mT; lower fields increase noise and reduce resolution.

Is the exposed thermal pad electrically connected internally?

No - the exposed pad is a thermal and mechanical feature only, with no internal electrical connection. It must be soldered to a GND plane for optimal thermal dissipation (θ_JC = 12°C/W), mechanical stability, and EMI reduction, but does not serve as a functional pin.

How does the SpinAxis™ method differ from traditional arctangent-based angle calculation?

SpinAxis™ uses phase detection of sinusoidal Hall signals instead of computing arctan(Y/X), eliminating interpolation errors, lookup tables, and feedback loops. This yields deterministic <4ms latency, no computational drift, and immunity to harmonic distortion - critical for consistent HMI response in automotive environments.

What happens if the 20ms delay is omitted after an SPI register write?

Omitting the 20ms NVM programming delay causes the second SPI frame to read back stale register contents - the prior value - because the write has not completed. This leads to undetected misconfiguration; the delay is mandatory and cannot be shortened, even at elevated temperatures.