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AS5030

Datasheet - Application In formatio n

anti-aliasing filter. The filter characteristic must be chosen carefully to balance propagation delay and noise.

The low-pass filter in the AS5030 has a cut-off frequency of typ. 23.8kHz and the overall propagation delay in the analog signal path is typ.

15.6µs.

considered. Due to its nature, a PWM signal is not very usable at high speeds, as you get only one reading per PWM period. Increasing the

PWM frequency may improve the situation but causes problems for the receiving controller to resolve the PWM steps. The frequency on the

AS5030 PWM output is typ. 1.95kHz with a resolution of 2µs/step.

A more suitable approach for high speed absolute angle measurement is using the serial interface. With a clock rate of up to 6MHz, a complete

set of data (21bits) can be read in >3.5µs

8.6.2 Total Propagation Delay of the AS5030

The total propagation delay of the AS5030 is the delay in the analog signal path and the tracking rate of the ADC:

15.6µs + 1.15µs = 16.75µs.

If only the SIN-/COS-outputs are used, the propagation delay is the analog signal path delay only (typ. 15.6µs).

Position Error over Speed.

The angle error over speed caused by the propagation delay is calculated as:

(EQ 4)

In addition, the anti-aliasing filter causes an angle error calculated as:

(EQ 5)

Examples of the overall position error caused by speed, including both propagation delay and filter delay:

8.7 Reduced Power Modes

The AS5030 can be operated in 3 reduced power modes. All 3 modes have in common that they switch off or freeze parts of the chip during

intervals between measurements. In Low Power Mode or Ultra-low Power Mode, the AS5030 is not operational, but due to the fast start-up, an

angle measurement can be accomplished very quickly and the chip can be switched to reduced power immediately after a valid measurement

has been taken. Depending on the intervals between measurements, very low average power consumption can be achieved using such a

strobed measurement mode.



Low Power Mode:reduced current consumption, very fast start-up. Ideal for short sampling intervals (<3ms)



Ultra-low Power Mode:further reduced current consumption, but slower start-up than Low Power Mode. Ideal for sampling intervals from

3….200ms



Power Cycle mode:zero power consumption (externally switched off) during sampling intervals, but slower start-up than Ultra-low Power

Mode. Ideal for sampling intervals 200ms

Speed (rpm)

Total Position Error

100

0.0175°

1000

0.175°

10000

1.75°