FATEK SD3 Series, Instruction Manual, Page: 394 / 396

32
t1
t2
2 MHz
(500 ns)
(250 ns)
Duty50 %
125 ns（＝250 ns/2）
9. Appendices
SD3 Series Instruction Manual
5. How to Set Pulse train command: Input filter (33.0)
Tip for Filter Setup
5. How to set Pulse train command: Input filter (No.33.0)
Pulse Train Command Input Filter (No.33.0) is a function to reduce malfunction caused by noise.
Select a value for the pulse width that you want the filter to pass Pulse Train Command input signal.
Pulse Train Command input is open collector, be sure to select the best filter.
Setting Passing pulse width [ns]
0 No filter
1 25
2 50 (4 MHz)
3 100
4 150 (2 MHz)
5 200
6 300 (1 MHz)
7 400
Setting Passing pulse width [ns]
8 600 (500 kHz)
9 800
10 1,000
11 1,200
12 1,600 (250 kHz)
13 2,000
14 2,300
15 3,100
・When the input frequency is high, select a small passing pulse width.
・To improve noise resistance, select a larger passing pulse width.
・Set the passing pulse width to be 1/3 to 1/2 of the input pulse width.
Example: Input pulse of 2 MHz with 50% duty cycle
Because the input pulse width is 250 ns, set No.33.0 to 3 or 4 so that pulses to pass the filter will be 125 ns or
less. (The default is 4)
( ) recommended when input
Selecting the best filter value using the pulse frequency by pulse duty cycle matrix
Duty [%]
Pulse Frequency
50 40 30 20 10
100 kHz 12 11 10 8 6
200 kHz 9 8 7 6 4
The minimum value of t1 or t2 is the passing pulse width.
Input pulse
Input pulse
Passing pulse width
Input pulse width