DocID031065 Rev 2

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STSPIN820

Functional description

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5.2

Microstepping sequencer

At each STCK rising edge, the sequencer of the device is increased (DIR input high) or

decreased (DIR input low) of a module selected through the MODEx inputs as listed in

Table 7.

The sequencer is a 10-bit counter that sets the reference value of the PWM current

controller and the direction of the current for both of the full-bridges.

Note:

The MODE1, MODE2 and MODE3 configuration can be changed in any time and it is

immediately applied.

Figure 4. MODEx, STCK and DIR timing diagram

Table 7. Step mode selection through MODEx inputs

MODE3

MODE2

MODE1

Step mode

Counter module (binary)

0

0

0

Full-step

0100000000

0

0

1

½ step

0010000000

0

1

0

¼ step

0001000000

01

1

0000100000

10

0

0000010000

10

1

0000001000

1

1

0

0000000010

1

1

1

0000000001