AS5045

Data Sheet

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Revision 1.7

22 – 33

13 3.3V / 5V Operation

The AS5045 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.

For 3.3V operation, the LDO must be bypassed by connecting VDD3V3 with VDD5V (see Figure 16).

For 5V operation, the 5V supply is connected to pin VDD5V, while VDD3V3 (LDO output) must be buffered by a

2.2...10µF capacitor, which is supposed to be placed close to the supply pin (see Figure 16).

The VDD3V3 output is intended for internal use only It must not be loaded with an external load (see Figure 16).

Figure 16. Connections for 5V / 3.3V Supply Voltages

LDO

I

N

T

E

R

F

A

C

E

2.2...10µF

100n

4.5 - 5.5V

DO

Prog

CLK

PWM

VDD3V3

VSS

VDD5V

5V Operation

Internal

VDD

CSn

LDO

100n

3.0 - 3.6V

VDD3V3

VSS

VDD5V

3.3V Operation

Internal

VDD

I

N

T

E

R

F

A

C

E

DO

Prog

CLK

PWM

CSn

A buffer capacitor of 100nF is recommended in both cases close to pin VDD5V. Note that pin VDD3V3 must always

be buffered by a capacitor. It must not be left floating, as this may cause an instable internal 3.3V supply voltage

which may lead to larger than normal jitter of the measured angle.