Monolithic Power Systems Inc. MA820GQ-P

Overview

MA820GQ-P from Monolithic Power Systems is an 8-bit contactless magnetic angle encoder with ABZ quadrature output and dual magnetic field threshold detection for push/pull button functionality. It replaces potentiometers in manual controls, delivers programmable 1–64 pulses per channel per revolution via SPI, operates at up to 200 rpm, and features on-chip NVM for zero-angle, pulse count, and threshold storage.

For engineers reviewing the MA820GQ-P datasheet, MA820GQ-P pinout, MA820GQ-P application, or MA820GQ-P equivalent, this page provides verified technical context, ABZ timing behavior, magnetic field threshold calibration, SPI register mapping, and QFN-16 layout guidance for human-machine interface designs requiring robust, wear-free angular sensing.

Technical Context

The MA820GQ-P uses Spinaxis™ phase-detection architecture-measuring magnetic field direction via time-to-digital conversion of sinusoidal zero-crossings-enabling open-loop 8-bit absolute angle output at 850–1100 kHz refresh rate without arctangent computation or feedback loops. Its front-end delivers raw angle data at 1 MHz before digital filtering.

ABZ incremental output is generated by internal edge synthesis synchronized to a 16 MHz clock, with programmable hysteresis (2.1°) and jitter bounded at 0.4° (overall), while MGH/MGL logic outputs respond to field strength crossing independently set MGHT/MGLT thresholds (3-bit resolution, ±6 mT hysteresis, -600 ppm/°C drift).

Key Specifications

Pinout & Package

MA820GQ-P is housed in a thermally enhanced QFN-16 package (3 mm × 3 mm, 0.5 mm pitch) with exposed thermal pad recommended for grounding. Pin numbering follows standard top-view orientation with Pin 1 at top-left corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS5048B and TMR2003D, MA820GQ-P uniquely integrates ABZ hardware generation, dual magnetic threshold logic, and on-chip NVM in a single QFN-16 package-reducing BOM count and firmware overhead for cost-sensitive HMI and appliance designs.

Availability

MA820GQ-P is available at Aetrix Electronics and suitable for rotary knob control interfaces, automotive HVAC actuators, and white goods motor position feedback requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MA820GQ-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 ICs, with design centers in the U.S., China, and Taiwan.

The MagAlpha® family-including MA820GQ-P-is engineered for contactless angular position sensing in human-machine interfaces, replacing potentiometers and optical encoders with robust, programmable magnetic solutions.

FAQ

What magnet configuration is required for reliable MA820GQ-P operation?

The MA820GQ-P is optimized for diametrically magnetized cylindrical neodymium (N35) magnets, typically Ø5 mm × 3 mm, mounted with ≤1.0 mm airgap. Field strength must exceed 30 mT at the sensor's sensitive volume (centered within 50 µm of package surface); performance degrades below this threshold, with linearity and resolution falling outside spec.

How is the zero-angle position programmed and retained?

Zero angle is set by writing a 16-bit complementary value to registers 0x0 and 0x1 (Z[15:0]) via SPI. This value is stored in on-chip non-volatile memory and automatically loaded at power-on. For example, to set zero at 20°, write decimal 61895 (0xF1C7) across both registers-no external memory or calibration routine needed.

Can MA820GQ-P generate true differential ABZ signals?

Yes-MA820GQ-P provides fully differential ABZ outputs: A and /A, B and /B, Z and /Z. Each pair is internally matched for timing and drive strength, enabling noise-rejecting RS-422-style reception without external comparators or line drivers.

What is the maximum rotational speed supported for accurate ABZ output?

The MA820GQ-P maintains specified ABZ jitter (≤0.4°) and edge accuracy up to 200 rpm. At higher speeds, systematic jitter increases due to finite update rate (16 MHz ABZ clock) and mechanical limitations of magnet mounting-not electrical limits of the IC itself.

How does the programmable filter cutoff affect latency and noise?

The 90 Hz low-pass filter reduces angle noise without adding steady-state latency; propagation delay remains fixed at 4 ms under constant-speed rotation. Lowering cutoff further (via custom firmware or future revisions) would increase latency, but 90 Hz is the only factory-set value-no user adjustment is possible.

Is the exposed thermal pad electrically connected internally?

No-the exposed pad is a thermal and mechanical feature only, not tied to any internal node. MPS recommends connecting it to GND for optimal thermal dissipation (θJC = 12 °C/W), mechanical stability, and EMI shielding-but it may be left floating if PCB layout constraints prevent grounding.

What happens if the 20 ms NVM write delay is not observed during SPI register programming?

If less than 20 ms elapses between the first (write command) and second (acknowledge) SPI frames, the non-volatile memory write fails silently-the register retains its previous value, and the second frame returns the old content. This is a hard timing requirement, not a recommendation.