AS5040-ASSU austriamicrosystems, AS5040-ASSU Datasheet - Page 15

• Manufacturer Part Number: AS5040-ASSU
• Description: IC ENCODER PROG 10-BIT 16-SSOP
• Manufacturer: austriamicrosystems
• Type: Linear, Rotary Encoder - Programmabler

Specifications of AS5040-ASSU

• Sensing Range: 45mT ~ 75mT
• Voltage - Supply: 3 V ~ 3.6 V, 4.5 V ~ 5.5 V
• Current - Supply: 21mA
• Current - Output (max): 4mA
• Output Type: Quadrature with Index (Incremental)
• Features: Programmable
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 16-SSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AS5040
Data Sheet
Table 5: PWM Signal Parameters
10 Analog Output
An analog output may be generated by averaging the PWM signal, using an external active or passive lowpass filter.
The analog output voltage is proportional to the angle: 0°= 0V; 360° = VDD5V.
Using this method, the AS5040 can be used as direct replacement of potentiometers.
Figure 11: Simple Passive 2
R1,R2 ≥ 4k7
R1 should be ≥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.
11 Brushless DC Motor Commutation Mode
Brushless DC motors require angular information for stator commutation. The AS5040 provides U-V-W commutation
signals for one and two pole pair motors. In addition to the three-phase output signals, the step (LSB) output at pin 12
allows high accuracy speed measurement. Two resolutions (9 or 10 bit) can be selected by programming Div0
according to Table 6.
Mode 3.0 (3.1) is used for brush-less DC motors with one-pole pair rotors. The three phases (U, V, W) are 120
degrees apart, each phase is 180 degrees on and 180 degrees off.
Mode 3.2 (3.3) is used for motors with two pole pairs requiring a higher pulse count to ensure a proper current
commutation. In this case the pulse width is 256 positions, equal to 90 degrees.
The precise physical angle at which the U, V and W signals change state (“Angle” in Figure 12 and Figure 13) is
calculated by multiplying each transition position by the angular value of 1 count:
Angle [deg] = Position x (360 degree / 1024)
www.austriamicrosystems.com
PWM frequency
MIN pulse width
MAX pulse width
Parameter
Pin12
PWM
C1,C2 ≥ 1µF / 6V
Pin7
VSS
Symbol
nd
PW
PW
f
Order Lowpass Filter
PWM
MAX
MIN
R1
C1
0.9756
1024
Typ
1
R2
Revision 2.10
Unit
kHz
µs
µs
C2
Signal period: 1025µs
- Position 0d
- Angle 0 deg
- Position 1023d
- Angle 359,65 deg
analog out
VDD
0V
2
2
0°
360°
Note
15 - 33