Monolithic Power Systems Inc. MA800GQ-P

Overview

MA800GQ-P from Monolithic Power Systems is an 8-bit contactless absolute angle encoder IC that replaces potentiometers and rotary switches in human-machine interface applications. It delivers 8-bit resolution (0.005° rms noise), operates at up to 200 rpm, supports SPI/SSI digital interfaces, and integrates push/pull button detection via programmable magnetic field thresholds (MGL/MGH outputs). It is used in rotary knob controls requiring wear-free position sensing.

For engineers reviewing the MA800GQ-P datasheet, MA800GQ-P pinout, MA800GQ-P application, or MA800GQ-P equivalent, this page provides verified technical context, validated pin functions, confirmed magnetic field threshold behavior (±5 mT accuracy), real-world mounting constraints (≤0.5 mm positioning tolerance), and SPI/SSI timing compliance per MPS Rev. 1.1 specification.

Technical Context

The MA800GQ-P implements Spinaxis™ phase-detection architecture using integrated Hall devices to digitize magnetic field direction without arctangent computation or feedback loops. Its front-end outputs a 1 MHz time-to-digital signal proportional to angular position, processed by a configurable first-order low-pass filter (Fcutoff = 90 Hz, τ = 0.38/Fcutoff).

Digital conditioning includes on-chip non-volatile memory for zero-angle offset (16-bit), rotation direction (CW/CCW), and dual magnetic thresholds (MGHT/MGLT, 3-bit each). Push/pull button logic is implemented via two independent open-drain outputs (MGH/MGL) with 6 mT hysteresis and -600 ppm/°C temperature drift.

Key Specifications

Pinout & Package

MA800GQ-P is housed in a QFN-16 (3 mm × 3 mm, 0.5 mm height) package with exposed thermal pad (Pin 17). The package supports reflow soldering (260°C peak) and requires grounding the exposed pad for optimal thermal/electrical performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS5600 and TMAG5170, MA800GQ-P uniquely integrates push-button logic, on-chip NVM for zero/rotation/threshold storage, and dual-interface support - reducing system-level complexity for cost-sensitive HMI designs.

Availability

MA800GQ-P is available at Aetrix Electronics and suitable for rotary knob control interfaces, manual controls, and automotive HVAC actuators requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MA800GQ-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) 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 product line targets contactless position sensing for human-machine interfaces, emphasizing ease-of-use, robust magnetic field tolerance, and integrated digital interfaces - specifically engineered for knob, dial, and actuator applications.

FAQ

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

The MA800GQ-P is specified for operation up to 200 rpm. This limit ensures accurate angle capture within its 980 kHz refresh rate and 4 ms latency, avoiding aliasing or missed samples during manual rotation. Exceeding 200 rpm may cause interpolation errors due to finite sampling resolution and magnetic field slew rate limitations.

How is the zero-angle position programmed and retained?

The zero-angle offset is programmed via SPI write to registers 0 and 1 (Z[15:0]), stored in on-chip non-volatile memory, and automatically reloaded at power-on. The value represents the complementary angle (360° – desired zero), calculated using Z = 2¹⁶ – (a₀ × 2¹⁶ / 360°). No external EEPROM or MCU storage is required.

Can the MA800GQ-P operate with magnets other than diametrically magnetized cylinders?

Yes - the MA800GQ-P detects in-plane magnetic field components and supports ring, disc, or block magnets, provided the field remains ≥30 mT and lies primarily parallel to the package surface. Performance specifications (INL, noise) are guaranteed only with diametrically magnetized Ø2–8 mm cylinders per MPS application guidance.

What is the purpose of the TEST pin (Pin 10)?

Pin 10 (TEST) is reserved for factory testing and must be connected to GND in all end-user applications. Leaving it floating may cause undefined behavior or communication errors. It is not intended for debug, calibration, or user-accessible functionality.

Does the MA800GQ-P require external passive components for basic operation?

Yes - a 1 µF ceramic decoupling capacitor must be placed between VDD (Pin 13) and GND (Pin 8) with minimal trace length. No pull-up/pull-down resistors are needed on SPI/SSI lines due to internal biasing (e.g., CS has internal pull-up; SCLK/MOSI have internal pull-downs).

How does the SSI interface differ from standard SSI protocols?

The MA800GQ-P implements a proprietary SSI variant: SSCK idles low (not high), requires a dummy rising edge at frame start, and lacks register access capability. It is incompatible with standard SSI masters unless firmware accommodates these deviations - SPI is recommended for full configurability.

What is the guaranteed endurance of the on-chip NVM used for configuration storage?

The on-chip non-volatile memory is rated for 1,000 write cycles at 25°C. Each write operation (e.g., zero-angle update) requires a mandatory 20 ms delay between SPI frames to complete programming. Frequent writes outside this window risk incomplete writes or register corruption.