- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄1983 > AD7781CRZ (Analog Devices Inc)IC ADC 20BIT 1CH LP SD 14SOIC PDF資料下載
參數(shù)資料
| 型號(hào)： | AD7781CRZ |
| 廠商： | Analog Devices Inc |
| 文件頁數(shù)： | 7/16頁 |
| 文件大?。?/td> | 0K |
| 描述： | IC ADC 20BIT 1CH LP SD 14SOIC |
| 產(chǎn)品培訓(xùn)模塊： | Weigh Scale Introduction |
| 設(shè)計(jì)資源： | Weigh Scale Design Using AD7781 with Internal PGA (CN0108) |
| 標(biāo)準(zhǔn)包裝： | 56 |
| 位數(shù)： | 20 |
| 采樣率（每秒）： | 16.7 |
| 數(shù)據(jù)接口： | 串行，SPI? |
| 轉(zhuǎn)換器數(shù)目： | 1 |
| 電壓電源： | 單電源 |
| 工作溫度： | -40°C ~ 105°C |
| 安裝類型： | 表面貼裝 |
| 封裝/外殼： | 14-SOIC（0.154"，3.90mm 寬） |
| 供應(yīng)商設(shè)備封裝： | 14-SO |
| 包裝： | 管件 |
| 輸入數(shù)目和類型： | 1 個(gè)差分，雙極 |
| 產(chǎn)品目錄頁面： | 779 (CN2011-ZH PDF) |
AD7781
Rev. 0 | Page 15 of 16
GROUNDING AND LAYOUT
Because the analog input and reference input of the ADC are
differential, most of the voltages in the analog modulator are
common-mode voltages. The excellent common-mode reject-
tion of the part removes common-mode noise on these inputs.
The digital filter provides rejection of broadband noise on the
power supply, except at integer multiples of the modulator
sampling frequency. The digital filter also removes noise from
the analog and reference inputs, provided that these noise sources
do not saturate the analog modulator. As a result, the AD7781
is more immune to noise interference than conventional high
resolution converters. However, because the resolution of the
AD7781 is so high and the noise levels from the AD7781 are so
low, care must be taken with regard to grounding and layout.
The printed circuit board (PCB) that houses the AD7781 should
be designed so that the analog and digital sections are separated
and confined to certain areas of the board. A minimum etch
technique is generally best for ground planes because it gives
the best shielding.
It is recommended that the GND pin of the AD7781 be tied
to the AGND plane of the system. In any layout, pay attention
to the flow of currents in the system and ensure that the return
paths for all currents are as close as possible to the paths that the
currents took to reach their destinations. Avoid forcing digital
currents to flow through the AGND sections of the layout.
The ground plane of the AD7781 should be allowed to run under
the AD7781 to prevent noise coupling. The power supply lines
to the AD7781 should use as wide a trace as possible to provide
low impedance paths and reduce the effects of glitches on the
power supply line. Fast switching signals such as clocks should
be shielded with digital ground to avoid radiating noise to other
sections of the board, and clock signals should never be run near
the analog inputs. Avoid crossover of digital and analog signals.
Traces on opposite sides of the board should run at right angles
to each other. This reduces the effects of feedthrough through
the board. A microstrip technique is by far the best, but it is not
always possible with a double-sided board. In this technique,
the component side of the board is dedicated to ground planes,
and the signals are placed on the solder side.
Good decoupling is important when using high resolution ADCs.
AVDD should be decoupled with 10 μF tantalum capacitors in
parallel with 0.1 μF capacitors to GND. DVDD should be decoupled
with 10 μF tantalum capacitors in parallel with 0.1 μF capac-
itors to GND, with the system’s AGND to DGND connection
being close to the AD7781. To achieve the best results from
these decoupling components, place them as close as possible
to the device, ideally right up against the device. All logic chips
should be decoupled with 0.1 μF ceramic capacitors to DGND.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| AD7782BRUZ | IC ADC 24BIT 2CHAN 16TSSOP |
| AD7783BRU | IC ADC 24BIT 2CH R-R 16-TSSOP |
| AD7785BRUZ-REEL | IC ADC 20BIT 3CH LN LP 16-TSSOP |
| AD7787BRMZ | IC ADC 24BIT 2CH LP SIG 10MSOP |
| AD7789BRM | IC ADC 24BIT LP 10-MSOP |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| AD7781CRZ-REEL | 功能描述:IC ADC 20BIT 1CH LP SD 14SOIC RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 位數(shù):16 采樣率（每秒）:15 數(shù)據(jù)接口:MICROWIRE?，串行，SPI? 轉(zhuǎn)換器數(shù)目:1 功率耗散（最大）:480µW 電壓電源:單電源 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:38-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:38-QFN（5x7） 包裝:帶卷 (TR) 輸入數(shù)目和類型:16 個(gè)單端，雙極；8 個(gè)差分，雙極 配用:DC1011A-C-ND - BOARD DELTA SIGMA ADC LTC2494 |
| AD7782 | 制造商:AD 制造商全稱:Analog Devices 功能描述:Read Only, Pin Configured 24-Bit ADC |
| AD7782BRU | 制造商:Analog Devices 功能描述:ADC Single Delta-Sigma 20sps 24-bit Serial 16-Pin TSSOP 制造商:Analog Devices 功能描述:IC 24-BIT ADC |
| AD7782BRU-REEL | 功能描述:IC ADC 24BIT 2CH 16-TSSOP T/R RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:1,000 系列:- 位數(shù):16 采樣率（每秒）:45k 數(shù)據(jù)接口:串行 轉(zhuǎn)換器數(shù)目:2 功率耗散（最大）:315mW 電壓電源:模擬和數(shù)字 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:28-SOIC（0.295"，7.50mm 寬） 供應(yīng)商設(shè)備封裝:28-SOIC W 包裝:帶卷 (TR) 輸入數(shù)目和類型:2 個(gè)單端，單極 |
| AD7782BRU-REEL7 | 制造商:Analog Devices 功能描述:ADC Single Delta-Sigma 20sps 24-bit Serial 16-Pin TSSOP T/R |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。