AS5245 AMSCO [austriamicrosystems AG], AS5245 Datasheet - Page 18

• Manufacturer Part Number: AS5245
• Manufacturer: AMSCO [austriamicrosystems AG]

AS5245
Data Sheet - D e t a i l e d D e s c r i p t i o n
8.3.1 Changing the PWM Frequency
The PWM frequency of the AS5245 can be divided by two by setting a bit (PWMhalfEN) in the OTP register
page
Table 11. PWM Signal Parameters (default mode)
When PWMhalfEN = 1, the PWM timing is as shown in
Table 12. PWM Signal Parameters with Half Frequency (OTP option)
8.4 Analog Output
An analog output can be generated by averaging the PWM signal, using an external active or passive low pass filter. The analog output voltage
is proportional to the angle: 0º= 0V; 360º = VDD5V.
Using this method, the AS5245 can be used as direct replacement of potentiometers.
Figure 12. Simple 2nd Order Passive RC Low Pass Filter
Figure 12
R1 should be greater than or equal to 4k7 to avoid loading of the PWM output. Larger values of Rx and Cx will provide better filtering and less
ripple, but will also slow down the response time.
www.austriamicrosystems.com/AS5245
19). With PWMhalfEN = 0, the PWM timing is as shown in
Symbol
Symbol
PW
PW
PW
PW
f
f
shows an example of a simple passive low pass filter to generate the analog output.
PWM
PWM
MAX
MAX
MIN
MIN
MAX pulse width
MAX pulse width
PWM frequency
MIN pulse width
PWM frequency
MIN pulse width
Pin12
PWM
Parameter
Parameter
Pin7
VSS
R1,R2
R1
Table
C1
≥
4k7
12:
Table
R2
C1,C2
Revision 1.3
4096
8192
Typ
244
Typ
11:
C2
1
2
2
≥
1µF / 6V
analog out
VDD
0V
Unit
Unit
Hz
µs
µs
µs
µs
µs
0º
360º
Signal period: 4097µs
- Position 0d
- Angle 0 deg
- Position 4095d
- Angle 359,91 deg
- Position 0d
- Angle 0 deg
- Position 4095d
- Angle 359,91 deg
- Position 0d
- Angle 0 deg
(see Programming the AS5245 on
Note
Note
(EQ 2)
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