Delta ASDA-A3 Series User Manual page 621

Parameters

U, Y: filter width
If the pulse frequency is suddenly too high, causing a pulse width smaller than the set filter width,
then this pulse gets filtered out as noise. Therefore, set the filter width smaller than the actual pulse
8 width. You should set the filter width as 4 times smaller than the actual pulse width.
U and Y values
Example:
When U is set to 1 and Y is set to 1 (and filter width is therefore 0.2 μs), and when the high and low
duty width of the command pulse are both larger than 0.8 μs (and filter width is 4 times 0.2 μs), then
the pulse command is not filtered out.
When the high or low duty width of the pulse is smaller than the filter width, then it is filtered out.
Pulse input
Filtered signal
If the first pulse width is smaller than 0.8 μs,
the pulse may be filtered out, and thus two input
pulses will be regarded as one pulse. If the pulse
width is smaller than 0.2 μs, the pulse will be
filtered out.
If you use a 125 ns (4 Mpps) input pulse, set the filter width value Y to 0 to disable the filter function.
Note: when the signal is a high-speed pulse (4 Mpps) and the value of the filter width is 0, then the pulse is not filtered
out.
8-44
Filter width
Unit: μs (kHz)
0, 0 No filter function
0, 1 2 (250)
0, 2 3 (166)
0, 3 4 (125)
0, 4 5 (100)
0, 5 6 (83)
0, 6 7 (71)
0, 7 8 (62)
0, 8 9 (55)
0, 9 10 (50)
0, A 11 (45)
0, B 12 (41)
0, C 13 (38)
0, D 14 (35)
0, E 15 (33)
< 0.8 μs
0.8 μs
U and Y values
1, 0
1, 1
1, 2
1, 3
1, 4
1, 5
1, 6
1, 7
1, 8
1, 9
1, A
1, B
1, C
1, D
1, E
>0.8 μs
>0.8 μs
Pulse input
Filtered signal
If the low level pulse width is smaller than 0.8 μs,
the pulse may be filtered out, and thus two input
pulses will be regarded as one pulse. If the low
level pulse width is smaller than 0.2 μs, the pulse
will be filtered out.
Filter width
Unit: μs (kHz)
No filter function
0.2 (2500)
0.3 (1666)
0.4 (1250)
0.5 (1000)
0.6 (833)
0.7 (714)
0.8 (625)
0.9 (555)
1 (500)
1.1 (454)
1.2 (416)
1.3 (384)
1.4 (357)
1.5 (333)
< 0.8 μs
0.8 μs
ASDA-A3