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AS5130

Datasheet - Detailed Descr i pti on

The best performance of the AS5130 will be achieved when operating within the AGC range. It will still be operational outside the AGC range, but

with reduced performance especially with a weak magnetic field due to increased noise.

The initial strength of the magnet. Aging magnets may show a reducing magnetic field over time which results in an increase of the AGC

value. The effect of this phenomenon is relatively small and can easily be compensated by the AGC.

The vertical distance of the magnet. Depending on the mechanical setup and assembly tolerances, there will always be some variation of

the vertical distance between magnet and IC over the lifetime of the application using the AS5130. Again, vertical distance variations can be

compensated by the AGC.

The temperature and material of the magnet. The recommended magnet for the AS5130 is a diametrically magnetized 6mm diameter

magnet. Other magnets may also be used as long as they can maintain to operate the AS5130 within the AGC range. Every magnet has a

temperature dependence of the magnetic field strength. The temperature coefficient of a magnet depends on the used material. At elevated

temperatures, the magnetic field strength of a magnet is reduced, resulting in an increase of the AGC value. At low temperatures, the mag-

netic field strength is increased, resulting in a decrease of the AGC value. The variation of magnetic field strength over temperature is auto-

matically compensated by the AGC.

at normal operating temperature should be in the middle between minimum and maximum, hence it should be around 32 (20H). To facilitate the

“vertical centering” of the magnet+IC assembly, the sensitivity of the AS5130 can be adjusted in the OTP register in 8 steps (see Table 10). The

OTP sensitivity setting corresponds to the customer register setting gain <2:0>.

7.6 “Pushbutton” Feature

Using the magnetic field strength software and hardware indicators described above, the AS5130 provides a useful method of detecting both

rotation and vertical distance simultaneously. This is especially useful in applications implementing a rotate-and-push type of human interface

(e.g. in panel knobs and switches).

The CAO output is low, when the magnetic field is below the low limit (weak or no magnet) and high when the magnetic field is above the low limit

(in-range or strong magnet).

A finer detection of a vertical distance change, for example when only short vertical strokes are made by the pushbutton, is achieved by

memorizing the AGC value in normal operation and triggering on a change from that nominal the AGC value to detect a vertical movement.

Figure 15. Magnetic Field Strength Indicator

AS5130

100n

+5V

CS

DCLK

DIO

AS5130

C1

I/O

Output

Output

CAO

1k

LED1