Monolithic Power Systems Inc. MA800GQ-Z

Overview

MA800GQ-Z from Monolithic Power Systems is an 8-bit contactless absolute angle encoder IC with integrated push-button detection, designed to replace potentiometers and rotary switches in human-machine interface applications. It delivers 8-bit resolution (0.005° rms noise), operates at up to 1100 kHz refresh rate, supports SPI/SSI digital interfaces, and functions across –40°C to +125°C with 3.3V supply.

For engineers reviewing the MA800GQ-Z datasheet, MA800GQ-Z pinout, MA800GQ-Z application, or MA800GQ-Z equivalent, this page provides verified technical context, validated pin functions, confirmed magnetic field threshold behavior, real-world mounting constraints, and precise SPI/SSI timing compliance - all critical for knob control, automotive HMI, and white goods encoder design.

Technical Context

The MA800 uses Spinaxis™ phase-detection architecture - measuring magnetic field direction via time-to-digital conversion of sinusoidal Hall signals - eliminating arctangent computation or closed-loop interpolators. Its front-end outputs raw angle data at 1 MHz before digital filtering.

Dual-mode serial interface supports SPI Mode 0/3 (up to 25 MHz) for full register read/write and SSI (non-standard low-idle SSCK with dummy edge) for angle-only streaming. On-chip NVM stores zero-angle offset, rotation direction, and programmable MGLT/MGHT thresholds (3-bit each, ±6 mT hysteresis).

Key Specifications

Pinout & Package

MA800GQ-Z is housed in a QFN-16 (3 mm × 3 mm) package with exposed thermal pad. Pin 17 is the exposed pad, recommended to be connected to GND for optimal thermal, electrical, and mechanical performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS5600-DSO and TMAG5170-Q1, MA800GQ-Z uniquely integrates push/pull button logic, on-chip zero-angle NVM storage, and dual SPI/SSI support - making it optimal for cost-sensitive, space-constrained HMI designs where mechanical simplicity and fast integration are essential.

Availability

MA800GQ-Z is available at Aetrix Electronics and suitable for rotary knob control interfaces, automotive HVAC systems, white goods user panels, and industrial manual control systems requiring stable component supply, guaranteed lead-time adherence, and long-term lifecycle continuity.

Supply support for MA800GQ-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 across Asia and North America.

The MagAlpha product line delivers contactless magnetic position sensing ICs optimized for human-machine interface applications - emphasizing ease of integration, field-programmability, and robustness in consumer, automotive, and industrial environments.

FAQ

What is the maximum rotational speed supported by MA800GQ-Z?

The MA800GQ-Z is specified for slow-speed human-interface applications up to 200 rpm. Its 980 kHz refresh rate and <4 ms latency ensure accurate position capture even during rapid manual turns, but continuous high-speed rotation may exceed magnetic field tracking stability limits defined in the datasheet's dynamic response section.

Can MA800GQ-Z operate with magnets smaller than Ø2 mm?

No - the datasheet specifies Ø2–8 mm diametrically magnetized cylinders as the validated magnet size range. Smaller magnets produce insufficient field strength (<30 mT) at the sensor plane, degrading linearity (INL >1.1°) and effective resolution (rms noise >0.02°), which violates guaranteed specifications.

How is the zero-angle position programmed and retained?

The zero angle is set by writing a 16-bit complementary value to registers 0 and 1 (Z[15:0]), stored in on-chip non-volatile memory. This value persists across power cycles and requires no external backup; programming is performed via SPI write command with mandatory 20 ms NVM write delay.

Does MA800GQ-Z support standard SSI protocol?

No - its SSI implementation uses a low-idle SSCK signal and requires a dummy rising edge at frame start, differing from IEC 61158-6 standard SSI. It is incompatible with off-the-shelf SSI masters unless firmware accommodates these timing deviations, as documented in Figure 15 and Table 5.

What is the purpose of pins 2, 3, 6, 9, and 14 labeled NC?

These pins are internally unconnected and must remain floating - no external connection or PCB trace should be made. Leaving them unconnected prevents parasitic coupling, ensures signal integrity on adjacent functional pins (e.g., SCLK, MISO), and avoids violating the QFN-16 thermal and electrical design rules specified in the package drawing.

How does temperature affect magnetic threshold accuracy?

Magnetic threshold drift is –600 ppm/°C, meaning a 100°C rise causes ~6% shift in MGHT/MGLT trip points (e.g., 112 mT → ~105 mT). This is factored into the ±1.1° total INL spec; system-level calibration at end-of-line compensates for residual drift in precision applications.

Is the exposed thermal pad electrically isolated?

No - the exposed pad (Pin 17) is internally connected to GND. It must be soldered to a PCB ground plane using ≥4 thermal vias (0.3 mm diameter) to meet θJA = 50°C/W thermal resistance and prevent junction temperature exceedance above 125°C under 11.7 mA load.