21 - 37
Data Sheet - D e t a i l e d D e s c r i p t i o n
Figure 14. OTP Access Timing Diagram
7.6.6 Incremental Mode Programming
The following three different incremental output modes are available:
Mode: Md1=0 / Md0=1 sets the AS5140H in quadrature mode.
Mode: Md1=1 / Md0=0 sets the AS5140H in step / direction mode (see Table 2).
In both modes listed above, the incremental resolution may be reduced from 10 bit down to 9, 8 or 7 bit using the divider OTP bits Div1 and Div0
(see Table 20 below).
Mode: Md1=1 / Md0=1 sets the AS5140H in brushless DC motor commutation mode with an additional LSB incremental signal at pin 12
To allow programming of all bits, the default factory setting is all bits = 0. This mode is equal to mode 1:0 (quadrature A/B, 1LSB index width,
256ppr). The absolute angular output value, by default, increases with clockwise rotation of the magnet (top view). Setting the CCW-bit (see
Table 19) allows for reversing the indicated direction, e.g. when the magnet is placed underneath the IC:
- CCW = 0 – angular value increases clockwise;
- CCW = 1 – angular value increases counterclockwise.
By default, the zero / index position pulse is one LSB wide. It can be increased to a three LSB wide pulse by setting the Index-bit of the OTP
register. Further programming options (commutation modes) are available for brushless DC motor-control.
Md1 = Md0 = 1 changes the incremental output pins 3, 4 and 6 to a 3-phase commutation signal. Div1 defines the number of pulses per
revolution for either a two-pole (Div1=0) or four-pole (Div1=1) rotor.
In addition, the LSB is available at pin 12 (the LSB signal replaces the PWM-signal), which allows for high rotational speed measurement of up to
Operation Mode Selection