STMicroelectronics FlexSPIN: SPI configurable stepper and DC multi motor driver evaluation board EVAL6460 EVAL6460 Scheda Tecnica
Codici prodotto
EVAL6460
Power bridges
L6460
68/139
Doc ID 17713 Rev 1
An internal DAC is used to digitally control the output regulated current. The available values
are chosen to provide a quasi sinusoidal profile of the current. The current limit in each
phase is decided by PhADAC[3:0] bits for phase A and PhBDAC[3:0] bits for phase B. The
table below describes the relation between the value programmed in the stepper DAC and
the current level.
are chosen to provide a quasi sinusoidal profile of the current. The current limit in each
phase is decided by PhADAC[3:0] bits for phase A and PhBDAC[3:0] bits for phase B. The
table below describes the relation between the value programmed in the stepper DAC and
the current level.
Note:
The min and max values are guaranteed by testing the percentage of VSTEPREF that
allows the commutation of the Rsense comparator.
allows the commutation of the Rsense comparator.
I
MAX
=V
STEPREF
/ R
SENSE
.
To obtain the best phase approximation of a sinusoidal wave, the user needs to repeat the
final (100%) value. So the full values sequence should be as follows: 0, 1, 2, 3 … D, E, F, F,
F, E, D … 3, 2, 1, 0.
final (100%) value. So the full values sequence should be as follows: 0, 1, 2, 3 … D, E, F, F,
F, E, D … 3, 2, 1, 0.
Even if the total spread shows overlapping between current steps, the monotonicity is
guaranteed by design.
guaranteed by design.
When the internal sequencer the minimum angle resolution is nominally 5.625°, so
depending on the control mode chosen, the selectable steps are
depending on the control mode chosen, the selectable steps are
.
Table 24.
DAC
PhXDAC [3:0]
Phase current ratio respect to I
MAX
Min
Typ
Max
Unit
0000
(Hi-Z)
0001
-
9.8
-
% of I
MAX
0010
-
19.5
-
% of I
MAX
0011
-
29.0
-
% of I
MAX
0100
-
38.3
-
% of I
MAX
0101
-
47.1
-
% of I
MAX
0110
-
55.6
-
% of I
MAX
0111
-
63.4
-
% of I
MAX
1000
-
70.7
-
% of I
MAX
1001
-
77.3
-
% of I
MAX
1010
-
83.1
-
% of I
MAX
1011
-
88.2
-
% of IMAX
1100
-
92.4
-
% of I
MAX
1101
-
95.7
-
% of I
MAX
1110
-
98.1
-
% of I
MAX
1111
-
I
MAX
-