Curtis 1353 - Page 38

5 — SDO COMMUNICATIONS
Curtis 1353 CANopen Expansion Module Manual – June 2017 Return to TOC
pg. 34
Analog Input Algorithms
e voltage range of the six analog inputs is 0–15V and is scaled as 0–4095. e analog inputs are
sampled aer the nine driver output currents have been sampled. Each analog input is ltered by a
single pole exponential lter. e Filter Gain parameter is associated with the Timer Constant (TC)
of the lter, which indicates how long it takes the lter to respond to a step input and reach 63% of
the nal value. It takes approximately 5 TCs before the ltered signal reaches its full output. e table
below provides a way to estimate lter response.
FILTER VALUE
100%
63%
TIME
Time
Constant
Step Input
Filtered Response
Exponential Filter Response
Setting TC Time to 100%
1 64 s 320 s
2 32 s 160 s
4 16 s 80 s
8 8 s 40 s
16 4 s 20 s
32 2 s 10 s
64 1 s 5 s
128 512 ms 2.5 s
256 256 ms 1.25 s
512 128 ms 640 ms
1024 64 ms 320 ms
2048 32 ms 160 ms
4096 16 ms 80 ms
8192 8 ms 40 ms
16384 4 ms 20 ms
e analog input can be congured as voltage input type or as resistive input type. e value measured
at the six analog inputs is placed in the two MISO PDOs as ltered voltage (in units of 0.01 V) or
resistance (in units of ohms), depending on the input type.