Small (21x17mm) board for the AS5048A magnetic absolute angle sensor.
For use in motor control or robotics applications, the sensor precisely measures the orientation (angle in the plane) of a nearby diametrically magnetized magnet.
That sounds more complicated than using it really is, so lets describe it another way:
- attach the magnet to the axis of something that rotates
- put the sensor near it
- read precise angles with your Arduino
| Back of board | Front of board |
|---|---|
with SH 1.0 connector  |
with sensor  |
- 3.3V (default) or 5V (break solder bridge for 5V)
- 14 bit accuracy, 16384 positions per revolution
- SPI interface up to 10MHz
- PWM output pin with 1kHz PWM frequency and 12bit accuracy
- power indication LED (green, dim)
Datasheet of the sensor: https://ams.com/documents/20143/36005/AS5048_DS000298_4-00.pdf
You may be able to buy some here:
Or you could make one - it is open source, you will find gerber files and BOM in the repo, and design files for KiCad 6.
Please visit our discord: https://discord.gg/FwTymtVhMU
Or if you have found a problem, you can also open a bug-ticket here on GitHub.
The sensor has to be precisely positioned near the magnet. The magnet should be precisely on-axis and in-plane (no wobble!). The sensor should be mounted with an air-gap of about 0.5mm to the magnet.
Taking the time to mount the magnet and sensor board carefully will improve the accuracy and smoothness of your readings.
The sensor has an SPI interface:
The SPI interface is available on a JST-SH 6-pin socket. Pre-made cables are available cheaply on AliExpress and other sources.
You may connect VCC to either 3.3V or 5V.
Sensor board v1.1 (current version):
- If using 5V, break the connection between the solder bridge pads on the back side of the board.
- If using 3.3V, leave as is, do not break the solder-bridge.
Sensor board v1.0 (older version):
- If using 5V, leave the connection between the solder bridge pads on the back side of the board open.
- If using 3.3V, close the solder-bridge.
| 5V | 3.3V |
|---|---|
 |
 |
Connect the other lines (MOSI, MISO, CLK and CS) to the respective counterparts on your MCU board.
Note: The sensor board does not pull the CS line up.
SPI interface:
- SPI Mode 1
- MSB first
- max 10MHz SPI clock
See datasheet for details, or use an existing software driver.
The sensor can be used with any appropriate SPI driver.
The author uses it with Arduino-compatible MCU boards and the SimpleFOC library.
A driver for the sensor for Arduino and SimpleFOC can be found here: SimpleFOC drivers library
v1.1: 21 x 17 x 3.4mm (1mm PCB) v1.0: 21 x 17 x 4mm (1.6mm PCB)
Pre-made JST SH 1.0 cables are available. When buying cables with two plugs, choose the type that is called "reverse connection" - where the pins on both ends of the cable have the same order.
Some links to compatible cables / breakout boards: