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AS5145

Datasheet - Application In form atio n

9.3 3.3V / 5V Operation

The AS5145 operates either at 3.3V ±10% or at 5V ±10%. This is made possible by an internal 3.3V Low-Dropout (LDO) Voltage regulator. The

internal supply voltage is always taken from the output of the LDO, meaning that the internal blocks are always operating at 3.3V.

supposed to be placed close to the supply pin (see Figure 17) with recommended 2.2µF).

Note:

Figure 17. Connections for 5V / 3.3V Supply Voltages

It must not be left floating, as this may cause an instable internal 3.3V supply voltage which can lead to larger than normal jitter of the measured

angle.

9.4 Selecting Proper Magnet

Typically the magnet is 6mm in diameter and 2.5mm in height. Magnetic materials such as rare earth AlNiCo/SmCo5 or NdFeB are

recommended. The magnetic field strength perpendicular to the die surface has to be in the range of ±45mT…±75mT (peak).

The magnet’s field strength is verified using a gauss-meter. The magnetic field Bv at a given distance, along a concentric circle with a radius of

1.1mm (R1) is in the range of ±45mT…±75mT(see Figure 18).

Internal

VDD

LDO

I

N

T

E

R

F

A

C

E

VSS

VDD5V

VDD3V3

100nF

4.5 - 5.5V

+

2.2 ... 10µF

DO

PWM

CLK

CSn

PDIO

Internal

VDD

LDO

I

N

T

E

R

F

A

C

E

VSS

VDD5V

VDD3V3

3.0 - 3.6V

+

DO

PWM

CLK

CSn

PDIO

100nF

5V Operation

3.3V Operation