參數資料
型號: EVAL-AD7762EDZ
廠商: Analog Devices Inc
文件頁數: 14/29頁
文件大?。?/td> 0K
描述: BOARD EVAL CONTROL AD7762
標準包裝: 1
ADC 的數量: 1
位數: 24
采樣率(每秒): 625k
數據接口: 并聯
輸入范圍: ±3.25 Vpp
在以下條件下的電源(標準): 958mW @ 625kSPS
工作溫度: -40°C ~ 85°C
已用 IC / 零件: AD7762
已供物品: 板,CD
AD7762
Data Sheet
Rev. A | Page 20 of 28
PROGRAMMABLE FIR FILTER
As previously mentioned, the third FIR filter on the AD7762 is
user programmable. The default coefficients that are loaded on
reset are given in Table 10 and the frequency responses are
shown in Figure 31. The frequencies quoted in Figure 31 scale
directly with the output data rate.
Table 10. Default Filter Coefficients
No.
Dec.
Value
Hex
Value
No.
Dec.
Value
Hex
Value
0
53656736
332BCA0
24
700847
AB1AF
1
25142688
17FA5A0
25
70922
401150A
2
4497814
444A196
26
583959
408E917
3
11935847
4B62067
27
175934
402AF3E
4
1313841
4140C31
28
388667
5EE3B
5
6976334
6A734E
29
294000
47C70
6
3268059
31DDDB
30
183250
402CBD2
7
3794610
439E6B2
31
302597
4049E05
8
3747402
4392E4A
32
16034
3EA2
9
1509849
1709D9
33
238315
3A2EB
10
3428088
344EF8
34
88266
158CA
11
80255
1397F
35
143205
4022F65
12
2672124
428C5FC
36
128919
401F797
13
1056628
4101F74
37
51794
CA52
14
1741563
1A92FB
38
121875
1DC13
15
1502200
16EBF8
39
16426
402A
16
835960
40CC178
40
90524
401619C
17
1528400
4175250
41
63899
400F99B
18
93626
16DBA
42
45234
B0B2
19
1269502
135EFE
43
114720
1C020
20
411245
6466D
44
102357
18FD5
21
864038
40D2F26
45
52669
CDBD
22
664622
40A242E
46
15559
3CC7
23
434489
6A139
47
1963
7AB
The default filter should be sufficient for almost all applications.
It is a standard brick wall filter with a symmetrical impulse
response. The default filter has a length of 96 taps in non-
aliasing with 120 dB of attenuation at Nyquist. This filter not
only performs signal antialiasing, but also suppresses out-of-
band quantization noise produced by the analog-to-digital
conversion process. Any significant relaxation in the stop-band
attenuation or transition bandwidth relative to the default filter
can result in a failure to meet the SNR specifications.
To create a filter, note the following:
The filter must be even, symmetrical FIR.
The coefficients are in sign-and-magnitude format with
26 magnitude bits and sign coded as positive = 0.
The filter length must be between 12 taps and 96 taps in
steps of 12.
Because the filter is symmetrical, the number of
coefficients that must be downloaded is half the filter
length. The default filter coefficients exemplify this with
only 48 coefficients listed for a 96-tap filter.
Coefficients are written from the center of impulse
response (adjacent to the point of symmetry) outwards.
The coefficients are scaled so that the in-band gain of the
filter is equal to 134217726 with the coefficients rounded
to the nearest integer. For a low-pass filter, this is the
equivalent of having the coefficients sum arithmetically
(including sign) to a 67108863 (0x3FF FFFF) positive
value over the half-impulse response coefficient set
(maximum 48 coefficients). Any deviation from this
introduces a gain error.
–20
–40
–60
–80
–100
–120
–140
–160
0
100
400
500
300
200
600
FREQUENCY (kHz)
AM
P
L
IT
UDE
(
d
B)
0
05477-
044
–0.1dB FREQUENCY = 251kHz
PASS-BAND RIPPLE = 0.05dB
STOP BAND = 312.5kHz
–3dB FREQUENCY = 265kHz
Figure 31. Default Filter Frequency Response (625 kHz ODR)
The procedure for downloading a user-defined filter is detailed
相關PDF資料
PDF描述
EEM24DRST CONN EDGECARD 48POS DIP .156 SLD
EVAL-AD7191EBZ BOARD EVAL FOR AD7191
MIC2562A-1YM IC CTRLR PCMCIA CARDBUS 14SOIC
MIC2027-2YWM IC USB DISTRIB SW QUAD 16-SOIC
MIC2027-2YM IC USB DISTRIB SW QUAD 16-SOIC
相關代理商/技術參數
參數描述
EVAL-AD7763EB 制造商:Analog Devices 功能描述:EVALUATION BOARD I.C. - Bulk
EVAL-AD7763EBZ 制造商:Analog Devices 功能描述:EVALUATION BOARD I.C. - Bulk
EVAL-AD7763EDZ 功能描述:BOARD EVAL CONTROL AD7763 RoHS:是 類別:編程器,開發(fā)系統(tǒng) >> 評估板 - 模數轉換器 (ADC) 系列:- 產品培訓模塊:Obsolescence Mitigation Program 標準包裝:1 系列:- ADC 的數量:1 位數:12 采樣率(每秒):94.4k 數據接口:USB 輸入范圍:±VREF/2 在以下條件下的電源(標準):- 工作溫度:-40°C ~ 85°C 已用 IC / 零件:MAX11645 已供物品:板,軟件
EVAL-AD7764EBZ 制造商:Analog Devices 功能描述:EVAL BD FOR AD7764 - Bulk
EVAL-AD7764EDZ 功能描述:BOARD EVAL AD7764 RoHS:是 類別:編程器,開發(fā)系統(tǒng) >> 評估板 - 模數轉換器 (ADC) 系列:- 產品培訓模塊:Obsolescence Mitigation Program 標準包裝:1 系列:- ADC 的數量:1 位數:12 采樣率(每秒):94.4k 數據接口:USB 輸入范圍:±VREF/2 在以下條件下的電源(標準):- 工作溫度:-40°C ~ 85°C 已用 IC / 零件:MAX11645 已供物品:板,軟件