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AS5140H

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

(PWM_LSB).

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

10.000 rpm.

OTP Access

Setup Condition

Operation Mode Selection

Exit Condition

CSn

PROG

CLK