493
•
When detector EXE650B (interpolation magnification: 25) is used:
8MHz Clock
10MHz Clock
Switching
Max. Input
Frequency
fE max
Min. Edge
Interval
a min
Min. Pulse
Width
b min
Max. Input
Frequency
fE max
Min. Edge
Interval
a min
Min. Pulse
Width
b min
S3
S4
Approx.
60kHz
0.125
µ
s
0.125
µ
s
Approx.
60kHz
0.1
µ
s
0.1
µ
s
×
×
40kHz
0.25
µ
s
0.25
µ
s
50kHz
0.2
µ
s
0.2
µ
s
−
×
20kHz
0.5
µ
s
0.5
µ
s
25kHz
0.4
µ
s
0.4
µ
s
×
−
10kHz
1.0
µ
s
1.0
µ
s
12.5kHz
0.8
µ
s
0.8s
−
−
(
×
: Switch is closed)
2) Application Review
a) Linear Scale :
Input Frequency
=
Operation Speed
Scale Interval
=
1200
∕
60
0.01
=
2000PPS
<
EXE650B Max.InputFrequency
b) Min. Edge Interval and Pulse Width
DR2 receivable max. frequency : 675kHz
10
6
675000
×
4
=
0.3704
μ
s
<
Min. Edge Interval
•
With the above a) and b), switching S
3
and S
4
at 8MHz clock can be performed under
both of the following conditions:
Max. Input
Frequency
S
3
S
4
20kHz
×
−
10kHz
−
−
c) Feedback Frequency to Detector Output Frequency and Error Counter
Detector Output Frequency = 2000
×
25 = 50000PPS
!
50kPPS
Feedback Frequency = 50
×
4 = 200kPPS
d) DR2 User Constant (Cn-24, -25)
* Electronic Gear
=
B
A
=
Cn–24
Cn–25
=
Cn–2A
×
4
4
×
6
0.0001
×
10
=
6000
×
4
24000
=
1
1
G