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AS5130

Datasheet - Detailed Descr i pti on

Figure 9. PWM Output Signal

This means that the PWM pulse width is (position + 1) LSB, where position is 0….255.

The tolerance of the absolute pulse width and frequency can be eliminated by calculating the angle with the duty cycle rather than with the

absolute pulse width:

angle [ 8 - bit ] =

-1

(EQ 1)

angle [ º ] =

(EQ 2)

results in a degree value from 0º ...358.6º

Note:

7.1.4 Analog Output

The AS5130 can generate a ratiometric analog output voltage by low-pass filtering the PWM output. Figure 10 shows a simple passive 2nd order

low pass filter as an example. In order to minimize the ripple on the analog output, the cut-off frequency of the low pass filter should be well below

the PWM base frequency.

Table 8. PWM Signal Parameters

Position

Angle

LSB @ High

t_high

Low Column

t_low

Duty-Cycle

0

0º

1

0.556µs

256

142.3µs

0.39%

127

178.59º

128

71.15µs

129

71.7µs

49.4%

128

180º

129

71.7µs

128

71.15µs

50.2%

255

358.59º

256

142.3µs

1

0.556µs

99.6%

5V

PWM out

0.556µs

142.3µs

71.7µs

71.15µs

0.556µs

142.3µs

0

128

255

Position

257

t

ON

t

ON

t

OFF

+

--------------------------

⎝⎠

⎛⎞

360

256

---------

257

t

ON

t

ON

t

OFF

+

--------------------------

⎝⎠

⎛⎞

1

–