Monolithic Power Systems Inc. MA782GGU-Z

Overview

MA782GGU-Z from Monolithic Power Systems is an ultra-small, low-power contactless absolute angle sensor IC that detects the angular position of a diametrically magnetized rotating magnet using integrated 2D Hall-effect sensing and Spinaxis™ phase-detection architecture. It delivers 8–12-bit resolution, <0.5 µA idle current, and supports both on-axis and off-axis mounting for compact HMI and motion-sensing applications.

For engineers reviewing the MA782GGU-Z datasheet, MA782GGU-Z pinout, MA782GGU-Z application, or MA782GGU-Z equivalent, this page provides verified technical context, SPI interface timing constraints, magnetic field threshold configuration, NVM-backed zero-angle calibration, and power-mode transition behavior critical for battery-powered rotary encoder designs.

Technical Context

The MA782 employs a time-to-digital converter (TDC) to digitize magnetic field angle directly from sinusoidal phase detection-eliminating arctangent computation or feedback loops. Its front-end operates at 1 MHz, with digital filtering configurable via filter window (FW) settings to trade resolution (8–12 bit) against latency (4–16,000 µs) and noise (0.015–0.2° RMS).

Three power modes-Active (10 mA), Idle (<1 µA), and Automatic Sampling Cycle (ASC)-are controlled via EN/ASC pins or internal low-power clock. Magnetic field strength detection (MGL/MGH flags) uses configurable thresholds (±5 mT accuracy) with -600 ppm/°C drift, enabling axial position diagnostics and magnet health monitoring.

Key Specifications

Pinout & Package

MA782GGU-Z is housed in a QFN-14 (2 mm × 2 mm, 0.5 mm height) package with wettable flanks and exposed thermal pad. Pin 1 is marked by a dot; top-side marking includes "KV" product code, year code "Y", and lot number "LLL".

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar absolute angle sensing applications.

Compared with AS5600-DSO and TLE5012BE1000, the MA782GGU-Z uniquely combines sub-µA idle current, on-chip NVM, SPI interface, and magnetic field diagnostics in a 2 mm × 2 mm footprint-making it optimal for space- and energy-constrained consumer and industrial HMI.

Availability

MA782GGU-Z is available at Aetrix Electronics and suitable for portable device rotary controls, smart door lock actuation, and e-bike throttle position sensing requiring stable component supply, full lifecycle traceability, and RoHS-compliant sourcing.

Supply support for MA782GGU-Z 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) is a fabless semiconductor company specializing in high-performance power management and sensing solutions, with design centers in the US, China, and Taiwan.

The MagAlpha® family-including the MA782-is engineered for ultra-low-power, high-accuracy angular position sensing in space-constrained, battery-operated applications such as foldable displays, smart locks, and human-machine interfaces.

FAQ

What is the minimum magnetic field strength required for MA782GGU-Z to meet its specified INL accuracy?

The MA782GGU-Z requires ≥30 mT applied magnetic field to guarantee ±1.1° INL over temperature. Operation below 30 mT is possible but degrades linearity and resolution; performance deviation increases with field reduction and temperature extremes.

How does the MA782GGU-Z achieve <0.5 µA idle current while maintaining SPI accessibility?

In Idle mode, only the SPI interface block and NVM controller remain powered; the Hall front-end, TDC, and digital filter are fully disabled. The SPI bus stays responsive to /CS assertions, allowing immediate angle reads without full wake-up latency.

Can the MA782GGU-Z be used with a 1.8 V I/O supply while operating from a 3.3 V VDD?

Yes. VDDIO (Pin 12) accepts 1.8–3.6 V independently of VDD (Pin 13). At 1.8 V, VIH is 1.2 V min and VOL is 0.4 V max, enabling direct interfacing with 1.8 V microcontrollers without level shifters.

What is the purpose of the ND and DV pins, and how do they differ?

ND (Pin 10) asserts when new angle data is ready after a sampling cycle or threshold-triggered event. DV (Pin 14) asserts only when the digital filter output has fully settled-confirming stability for precision applications where transient artifacts must be rejected.

How is zero-angle calibration performed and retained across power cycles?

Zero-angle offset is written to register 0x00 and stored in on-chip NVM using the "Store All Registers to NVM" SPI command. During power-up, NVM contents are automatically loaded into registers, ensuring consistent reference alignment without host intervention.

Does the MA782GGU-Z support daisy-chaining multiple sensors on a single SPI bus?

No. The MA782GGU-Z uses a dedicated /CS pin per device and does not support multi-drop SPI. Each sensor requires individual /CS routing; shared SCLK/MISO/MOSI lines are permitted, but /CS must be discrete for address selection.

What PCB layout guidance is critical for reliable 25 MHz SPI operation?

Route SCLK with ground shielding on both sides and beneath the trace; place vias every 5 mm to connect ground planes; add a 200 Ω series resistor + 10 pF shunt capacitor near the MA782; match MISO/MOSI/SCLK lengths within 5 mm to minimize skew.