Datasheet

Data Sheet AD7194
Rev. A | Page 51 of 56
SUMMARY OF FILTER OPTIONS
The AD7194 has several filter options. The filter that is chosen
affects the output data rate, settling time, the rms noise, the stop
band attenuation, and the 50 Hz/60 Hz rejection.
Table 36 shows some sample configurations and the
corresponding performance in terms of throughput, settling
time and 50 Hz/60 Hz rejection.
Table 36. Filter Summary
1
Filter FS[9:0]
Output Data
Rate (Hz)
Settling
Time (ms) Throughput
2
(Hz) REJ60 50 Hz Rejection (dB)
3
Sinc
4
, Chop Disabled
4
1 4800 0.83 1200 0 No 50 Hz or 60 Hz rejection
Sinc
4
, Chop Disabled 5 960 4.17 240 0 No 50 Hz or 60 Hz rejection
Sinc
3
, Chop Disabled
5
960
3.125
320
0
No 50 Hz or 60 Hz rejection
Sinc
4
, Chop Disabled 480 10 400 2.5 0 120 dB ( 50 Hz and 60 Hz)
Sinc
3
, Chop Disabled 480 10 300 3.33 0 100 dB (50 Hz and 60 Hz)
Sinc
4
, Chop Disabled 96 50 80 12.5 0 120 dB (50 Hz only)
Sinc
4
, Chop Disabled 96 50 80 12.5 1 82 dB ( 50 Hz and 60 Hz)
Sinc
3
, Chop Disabled
96
50
60
16.7
0
95 dB (50 Hz only)
Sinc
3
, Chop Disabled 96 50 60 16.7 1 67 dB ( 50 Hz and 60 Hz)
Sinc
4
, Chop Disabled 80 60 66.67 15 0 120 dB (60 Hz only)
Sinc
3
, Chop Disabled 80 60 50 20 0 95 dB (60 Hz only)
Sinc
4
, Chop Disabled, Zero
Latency
96 12.5 80 12.5 0 120 dB (50 Hz only)
Sinc
4
, Chop Disabled, Zero
Latency
96
12.5
80
12.5
1
82 dB ( 50 Hz and 60 Hz)
Sinc
4
, Chop Disabled, Zero
Latency
80 15 66.67 15 0 120 dB (60 Hz only)
Sinc
4
, Chop Enabled 96 12.5 160 6.25 1 80 dB (50 Hz and 60 Hz)
Sinc
3
, Chop Enabled 96 16.7 120 8.33 1 67 dB (50 Hz and 60 Hz)
Fast Settling (Sinc
4
, Chop
Disabled, Average by 16)
96 2.63 380 2.63 1 100 dB (50 Hz and 60 Hz)
Fast Settling (Sinc
4
, Chop
Disabled, Average by 16)
96 2.78 360 2.78 1 94 dB (50 Hz and 60 Hz)
Fast Settling (Sinc
4
, Chop
Disabled, Average by 16)
5 50.53 19.79 50.53 0 40 dB (60 Hz only)
Fast Settling (Sinc
3
, Chop
Disabled, Average by 16)
5 53.33 18.75 53.33 0 40 dB (60 Hz only)
Fast Settling (Sinc
4
, Chop
Disabled, Average by 16)
6 42.10 23.75 42.1 0 40 dB (50 Hz only)
Fast Settling (Sinc
3
, Chop
Disabled, Average by 16)
6 44.44 22.5 44.44 0 40 dB (50 Hz only)
1
These calculations assume a 4.92 MHz stable master clock.
2
Throughput is the rate at which conversions are available when several channels are enabled. In zero latency mode, the output data rate and throughput are equal.
3
For fast settling mode, the 50 Hz/60 Hz rejection is measured in a band of ±0.5 Hz around 50 Hz and/or 60 Hz. For all other modes, a region of ±1 Hz around 50 Hz
and/or 60 Hz is used.
4
For output dates rates greater than 1 kHz, the sinc
4
filter is recommended.