MRMS501-001 | Murata | AMR anisotropic magnetoresistance magnetic switch sensor, non-Hall device, for detecting whether a magnet is present

MRMS501-001 

I. Appearance and packaging form

Package: MiniFLP-3 (A35) SMD, 3-pin, ultra-thin micro SMD package

Dimensions: 1.45 × 1.45 x 0.55 mm, very small in size, suitable for Murata Man...

Screen printing: code engraved on the chip surface (e.g., A95), not printing the complete model MRMS501 A-001; 3 metal solder pads, mounted on the surface of the PCB

Packaging: TR coil tape, 3000 pcs per roll

Temperature range: ‑40 ℃ ~ + 85 ℃, consumer / industrial grade, non-automotive grade

2. Core electrical parameters

form

project

Specifications

Sensing principle

AMR anisotropic magnetoresistance (different from Hall switch) Murata Manufacturing Co., Ltd.

Power supply voltage

1.6V-3.5V, typical 1.8V, suitable for lithium battery low voltage system

Average working current

3μA@1.8V , ultra-low power consumption, battery-friendly, Murata Manufacturing Co., Ltd.

Action magnetic field Hon

Maximum 2.5m T (magnet close to output flip)

Release the magnetic field Hoff

Minimum 0.5 mT (magnet removed to restore level)

Logic output

Open drain output, negative logic: magnetic output low level, non-magnetic output high level

Response frequency

8Hz, suitable for low-speed opening and closing detection, not suitable for high-speed rotating speed measurement, Murata Manufacturing Co., Ltd.

Output level

VOL=0.2V，VOH=1.6V

III. Working principle

The AMR magnetoresistive sensor detects the magnetic field of the external magnet;

Magnet near, magnetic field > Hon → output low (LOW)

Remove the magnet, magnetic field <Hoff → output raised (HIGH)

⚠️Negative logic, hardware design must pay attention, contrary to ordinary Hall switch logic, it is easy to fall into the pit. Only the magnetic field component on the surface of the parallel chip is detected, and the direction of the magnet placement directly determines whether it can trigger normally.

IV. Core advantages

The power consumption is extremely low, only 3μA, compared with the dozens to hundreds of μA of ordinary Hall switches, it is particularly suitable for battery-powered products and almost does not consume battery power. Murata Manufacturing Co., Ltd.

The package is very small, 1.45 mm in diameter and 0.55 mm in thickness, which is very friendly to the narrow space of notebooks and flip phones. Murata Man...

With a wide voltage of 1.6V, it is compatible with 1.8V main control systems and does not require a 3.3V power supply.

Compared with Hall, AMR has good detection stability under weak magnetic field conditions; Better temperature drift resistance than some Hall switches

SMD surface mount, large-scale automated production, 3Kpcs per tray, mature supply

V. Shortcomings in Selection & Design Considerations

The response frequency is only 8Hz, and it can only open and close the flip cover and detect the magnetic door. It cannot count the high-speed rotation. In high-speed scenes, you should choose Murata Man...

Negative logic output, open drain, external pull-up resistor is required, cannot be directly connected to MCU pin, hardware is very prone to errors

It only detects the magnetic field on the surface of the parallel chip, and the angle of the magnet is very important; The vertical arrangement of the magnetic field cannot trigger it, and the structural design needs to be simulated and verified.

The detection distance depends on the strength of the magnet; The weaker the magnet, the closer the detection distance; The Hon/Hoff threshold needs to be re-measured after the structural change.

Non-automotive grade, cannot be used in automotive electronics; Not suitable for harsh industrial environments with strong electromagnetic interference

There is a hysteresis interval of 0.5-2.5mT, and the structure design should reserve enough hysteresis margin to avoid output jitter.

VI. Typical Application Scenarios

Laptop lid sleep, close lid sleep, open lid wake screen (classic main scenario) Murata Manufacturing Co., Ltd.

Opening and closing detection of flip phones, handheld game consoles, and electronic dictionaries

Small home appliance door, flip cover magnetic detection, open lid lights up the indicator light

Portable IoT devices, battery-powered door magnet, box cover in place detection

Intelligent wearable accessories, storage box magnetic positioning detection

For technical and business consulting, please contact: 18277896808