3.6 Basic Operation Examples
CA5350
3-23
About settling time
Setting a large time for filter will reduce the noise, thereby improves the SNR of the
signal. However, settling time will also become longer. Relation between the filter rise
time and settling time is shown below (theoretical values).
Table 3-3 Filters
’ rise time and settling time
Filter setting
Settling time
10%
1%
1µs
1.19µs
1.70µs
3µs
3.57µs
5.11µs
10µs
11.9µs
17.0µs
30µs
35.7µs
51.1µs
100µs
119µs
170µs
300µs
357µs
511µs
1ms
1.19ms
1.70ms
3ms
3.57ms
5.11ms
10ms
11.9ms
17.0ms
30ms
35.7ms
51.1ms
100ms
119ms
170ms
300ms
357ms
511ms
Relation with frequency characteristics
The longer the filter rise time is set, the narrower the frequency bandwidth will be.
When high frequency component is required to be passed, set the filter to a small value.
Relation between the filter rise time and -3dB cutoff frequency is shown below
(theoretical values).
Table 3-4 Filters
’ rise time and bandwidth
Filter setting
-3dB cutoff frequency
1µs
340kHz
3µs
114kHz
10µs
34kHz
30µs
11.4kHz
100µs
3.4kHz
300µs
1.14kHz
1ms
340Hz
3ms
114Hz
10ms
34Hz
30ms
11.4Hz
100ms
3.4Hz
300ms
1.14Hz
