- 您现在的位置：买卖IC网 > PDF目录17049 > EVAL-AD7719EBZ (Analog Devices Inc)BOARD EVALUATION FOR AD7719 PDF资料下载
参数资料
| 型号： | EVAL-AD7719EBZ |
| 厂商： | Analog Devices Inc |
| 文件页数： | 5/40页 |
| 文件大小： | 0K |
| 描述： | BOARD EVALUATION FOR AD7719 |
| 标准包装： | 1 |
| ADC 的数量： | 2 |
| 位数： | 16，24 |
| 采样率（每秒）： | 105 |
| 数据接口： | 串行 |
| 输入范围： | 2 Vpp |
| 在以下条件下的电源（标准）： | 4.85mW @ 105SPS |
| 工作温度： | -40°C ~ 85°C |
| 已用 IC / 零件： | AD7719 |
| 已供物品： | 板 |
第1页第2页第3页第4页当前第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页
REV. A
AD7719
–13–
Both Channels
The operation of the aux channel is identical to the main
channel with the exception that there is no PGA on the aux
channel. The input chopping is incorporated into the input
multiplexer while the output chopping is accomplished by an
XOR gate at the output of the modulator. The chopped modulator
bit stream is applied to a Sinc
3 filter. The programming of the
Sinc
3 decimation factor is restricted to an 8-bit register SF; the
actual decimation factor is the register value times 8. The
decimated output rate from the Sinc
3 filter (and the ADC
conversion rate) will therefore be
f
SF
f
ADC
MOD
=×
×
×
1
3
1
8
where:
fADC is the ADC update rate.
SF is the decimal equivalent of the word loaded to the
filter register.
fMOD is the modulator sampling rate of 32.768 kHz.
Programming the filter register determines the update rate for
both the main and aux ADC. Both ADCs operate with the same
update rate.
The chop rate of the channel is half the output data rate.
The frequency response of the filter H (f) is as follows:
1
8
81
2
3
SF
f f
ff
MOD
OUT
×
×× ×
×
××
×
sin (
/
)
sin (
/
)
sin (
/
)
sin (
/
)
π
where:
fMOD = 32,768 Hz
SF = value programmed into SF SFR.
fOUT = fMOD/(SF
× 8 × 3)
The following shows plots of the filter frequency response for
the SF words shown in Table I. The overall frequency response
is the product of a Sinc
3 and a sinc response. There are Sinc3
notches at integer multiples of 3
× fADC and there are sinc notches
SINC3 FILTER
MUX
-
MOD1
XOR
ANALOG
INPUT
DIGITAL
OUTPUT
(8
SF )
3
1
2
AIN + VOS
AIN – VOS
fCHOP
fMOD
fCHOP
fADC
1
8
SF
3
(
)
Figure 5. Auxiliary ADC Channel Block Diagram
at odd integer multiples of fADC/2. The 3 dB frequency for all
values of SF obeys the following equation:
fdB
f
ADC
30 24
() =×
.
The signal chain is chopped as shown in Figures 4 and 5. The
chop frequency is
f
CHOP
ADC
=
2
As shown in the block diagram, the Sinc
3 filter outputs alternately
contain +VOS and –VOS, where VOS is the respective channel
offset. This offset is removed by performing a running average
of 2. This average by 2 means that the settling time to any change
in programming of the ADC will be twice the normal conversion
time, while an asynchronous step change on the analog input will
not be fully reflected until the third subsequent output.
t
f
t
SETTLE
ADC
=
=×
2
The allowable range for SF is 13 to 255, with a default of 69
(0x45). The corresponding conversion rates, conversion times,
and settling times are tabulated in Table I. Note that the con-
version time increases by 0.732 ms for each increment in SF.
Table I. ADC Conversion and Settling Times for Various
SF Words
SF
Data Update Rate
Settling Time
Word
fADC (Hz)
tSETTLE (ms)
13
105.3
19.04
69 (Default)
19.79
101.07
255
5.35
373.54
Normal mode rejection is the major function of the digital filter
on the AD7719. The normal mode 50 Hz ± 1 Hz rejection with an
SF word of 82 is typically –100 dB. The 60 Hz ± 1 Hz rejec-
tion with SF = 68 is typically –100 dB. Simultaneous 50 Hz and
60 Hz rejection of better than 60 dB is achieved with an SF of
69. Choosing an SF word of 69 places notches at both 50 Hz
and 60 Hz. Figures 6 to 9 show the filter rejection for a selec-
tion of SF words.
相关PDF资料 |
PDF描述 |
|---|---|
| EVAL-AD7266EDZ | BOARD EVAL FOR AD7266 A/D CONV |
| GCM22DCSH | CONN EDGECARD 44POS DIP .156 SLD |
| 0982660859 | CBL 17POS 0.5MM JMPR TYPE A 3" |
| 0210490326 | CABLE JUMPER 1.25MM .076M 26POS |
| MAX5138EVKIT+ | EVALUATION KIT FOR MAX5138 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| EVAL-AD7721CB | 制造商:Analog Devices 功能描述:EVALUATION BOARD FOR SINGLE SUPPLY, 12/16-BIT 312.5/468.75 KHZ SEGMA-DELTA ADC 制造商:Analog Devices 功能描述:EVALUATION BOARD - Bulk |
| EVAL-AD7722CB | 制造商:Analog Devices 功能描述:EVALUATION CONTROL BOARD I.C. - Bulk |
| EVAL-AD7722CBZ | 功能描述:BOARD EVALUATION FOR AD7722CBZ RoHS:是 类别:编程器，开发系统 >> 评估板 - 模数转换器 (ADC) 系列:- 产品培训模块:Obsolescence Mitigation Program 标准包装:1 系列:- ADC 的数量:1 位数:12 采样率（每秒）:94.4k 数据接口:USB 输入范围:±VREF/2 在以下条件下的电源（标准）:- 工作温度:-40°C ~ 85°C 已用 IC / 零件:MAX11645 已供物品:板，软件 |
| EVAL-AD7723CB | 制造商:Analog Devices 功能描述:EVALUATION CONTROL BOARD I.C. - Bulk |
| EVAL-AD7723CBZ | 功能描述:BOARD EVALUATION FOR AD7723 RoHS:是 类别:编程器，开发系统 >> 评估板 - 模数转换器 (ADC) 系列:- 产品培训模块:Obsolescence Mitigation Program 标准包装:1 系列:- ADC 的数量:1 位数:12 采样率（每秒）:94.4k 数据接口:USB 输入范围:±VREF/2 在以下条件下的电源（标准）:- 工作温度:-40°C ~ 85°C 已用 IC / 零件:MAX11645 已供物品:板，软件 |
发布紧急采购，3分钟左右您将得到回复。