- 您現在的位置：買賣IC網 > PDF目錄373923 > AD7889 (Analog Devices, Inc.) 12-Bit 600 kSPS ADC(單電源600kSPS12位A/D轉換器) PDF資料下載
參數資料
| 型號： | AD7889 |
| 廠商： | Analog Devices, Inc. |
| 英文描述： | 12-Bit 600 kSPS ADC(單電源600kSPS12位A/D轉換器) |
| 中文描述： | 12位600 ksps模數轉換器（單電源600kSPS12位的A / D轉換器） |
| 文件頁數： | 12/12頁 |
| 文件大小： | 285K |
| 代理商： | AD7889 |
AD7889
12
REV. B PRELIM. 7/97
Preliminary Technical Information
AD7889 to TMS320C20 Interface
Figure 7 shows the interface between the AD7889 (again in
Mode A) and the TMS320C20 DSP processor. Here a timer is
used to generate the
CONVST
pulse to ensure equidistant sam-
pling. For the TMS320C20 the CLKX, CLKR, FSX and FSR
should all be configured as inputs. The CLKX and CLKR
should be connected together as should the FSX and FSR.
AD7889
CONVST
RFS
SDATA
SCLK
TMS320C20
FSX
FSR
CLKR
CLKX
DR
TIMER
Figure7. AD7889 to TMS320C20 Interface
AD7889 to DSP56000 Interface
Figure 8 shows the interface between the AD7889 and the
DSP56000 DSP processor.Again a timer is used to start con-
version and the data is clocked on the subsuquent clock edges.
AD7889
CONVST
RFS
SDATA
TIMER
SCLK
DSP56000
SC1
SRD
SCK
Figure 8. AD7889 to DSP56000 Interface
Grounding and Layout
The analog and digital supplies to the AD7889 are indepen-
dent and separately pinned out to minimize coupling between
the analog and digital sections of the device. The part exhibits
good immunity to noise on the supplies but care must still
be taken with regard to grounding and layout especially when
using switching mode supplies.
The printed circuit board which houses the AD7889 should be
designed such that the analog and digital sections are separated
and confined to certain areas of the board. This facilitates the
use of ground planes which can be separated easily. A mini-
mum etch technique is generally best for ground planes as it
gives the best shielding. Digital and analog ground planes
should only be joined in one place. If the AD7889 is the only
device requiring an AGND to DGND connection, then the
ground planes should be connected at the AGND and DGND
pins of the AD7889. If the AD7889 is in a system where mul-
tiple devices require AGND to DGND connections, the con-
nection should still be made at one point only, a star ground
point which should be established as close as possible to the
AD7889.
Avoid running digital lines under the device as these will
couple noise onto the die. The analog ground plane should be
allowed to run under the AD7889 to avoid noise coupling. The
power supply lines to the AD7889 should use as large a trace
as possible to provide low impedance paths and reduce the ef-
fects of glitches on the power supply line. Fast switching sig-
nals like 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 will reduce
the effects of feedthrough through the board. A microstrip
technique is by far the best but is not always possible with a
double-sided board. In this technique, the component side of
the board is dedicated to ground planes while signals are
placed on the solder side.
Good decoupling is important when using high resolution ADCs.
All analog supplies should be decoupled with 10μF tantalum
in parallel with 0.1μF capacitors to AGND. To achieve the
best from these decoupling components, they have to be placed
as close as possible to the device, ideally right up against the de-
vice. All logic chips should be decoupled with 0.1μF disc
ceramic capacitors to DGND.In systems where a common
supply is used to drive both the AV
DD
and DV
DD
of the
AD7889, it is recommended that the systems AVDD supply is
used. In this case there should be a 10
resistor between the
AV
DD
pin and DV
DD
pin. This supply should have the recom-
mended analog supply decoupling capacitors between the V
DD
pin of the AD7889 and AGND and the recommended digital
supply decoupling capacitor between the V
DD
pin of the
AD7889 and DGND.
Evaluating the AD7889 Performance
The recommended layout for the AD7889 is outlined in the
evaluation board for the AD7889. The evaluation board pack-
age includes a fully assembled and tested evaluation board,
documentation and software for controlling the board from a
PC using the EVAL-CONTROL BOARD. The EVAL-
CONTROL BOARD can be used in conjunction with the
AD7889 evaluation board, as well as many other Analog De-
vices evaluation boards ending in the CB designator. Using the
EVAL-CONTROL BOARD with the AD7889 evaluation
board allows the user to evaluate the ac and dc performance of
the AD7889 on a PC.
The software provided with the evaluation board allows the
user to perform ac (Fast Fourier Transform) and dc (histo-
gram of codes) tests on the AD7889. The evaluation board can
also be used in a stand-alone fashion without the EVAL-CON-
TROL BOARD but in this case, the user has to write their
own software to evaluate the part. There are three versions of
the evaluation board available, one for the AD7889-1, one for
the AD7889-2 and one for the AD7889-3. The order numbers
for the evaulation boards are EVAL-AD7889-1CB, EVAL-
AD7889-2CB and EVAL-AD7889-3CB.
相關PDF資料 |
PDF描述 |
|---|---|
| AD7890AN-10 | DIN Audio Connector; No. of Contacts:6; Contact Termination:Solder; Mounting Type:Panel; Gender:Female; Terminal Type:Solder RoHS Compliant: Yes |
| AD7890AR-4 | Circular Connector Cable Assembly; Connector Type A:Circular Receptacle; Connector Type B:Stripped End Leads; Cable Length:10ft RoHS Compliant: Yes |
| AD7890BN-10 | SECURITY GUARD BLACK LOCKDOWN |
| AD7890BN-2 | Slide Switch; Circuitry:SPDT; Contact Current Max:4A; Switch Operation:On-On; Switch Terminals:Through Hole; Actuator Style:Vertical Flush; Leaded Process Compatible:Yes; Mounting Type:PCB; Switch Features:Vertical Flush Actuator RoHS Compliant: Yes |
| AD7890BN-4 | Slide Switch; Circuitry:SPDT; Contact Current Max:4A; Switch Operation:On-On; Switch Terminals:Through Hole; Leaded Process Compatible:Yes; Mounting Type:PCB; Switch Features:Vertical Actuator RoHS Compliant: Yes |
相關代理商/技術參數 |
參數描述 |
|---|---|
| AD7889-1ACBZ-500R7 | 功能描述:IC ADC 12BIT CTRLR TOUCH 12WLCSP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 觸摸屏控制器 系列:- 標準包裝:96 系列:- 類型:- 觸摸面板接口:- 輸入數/鍵:- 分辨率（位）:- 評估套件:* 數據接口:- 數據速率/采樣率 (SPS，BPS):- 電壓基準:- 電源電壓:- 電流 - 電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:16-TSSOP（0.173"，4.40mm 寬） 供應商設備封裝:16-TSSOP 包裝:帶卷 (TR) |
| AD7889-1ACBZ-RL | 功能描述:IC ADC 12BIT CTRLR TOUCH 12WLCSP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 觸摸屏控制器 系列:- 標準包裝:96 系列:- 類型:- 觸摸面板接口:- 輸入數/鍵:- 分辨率（位）:- 評估套件:* 數據接口:- 數據速率/采樣率 (SPS，BPS):- 電壓基準:- 電源電壓:- 電流 - 電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:16-TSSOP（0.173"，4.40mm 寬） 供應商設備封裝:16-TSSOP 包裝:帶卷 (TR) |
| AD7889-1ACBZ-RL7 | 功能描述:IC ADC 12BIT CTRLR TOUCH 12WLCSP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 觸摸屏控制器 系列:- 標準包裝:96 系列:- 類型:- 觸摸面板接口:- 輸入數/鍵:- 分辨率（位）:- 評估套件:* 數據接口:- 數據速率/采樣率 (SPS，BPS):- 電壓基準:- 電源電壓:- 電流 - 電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:16-TSSOP（0.173"，4.40mm 寬） 供應商設備封裝:16-TSSOP 包裝:帶卷 (TR) |
| AD7889ACBZ-500R7 | 功能描述:IC ADC 12BIT CTRLR TOUCH 12WLCSP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 觸摸屏控制器 系列:- 標準包裝:96 系列:- 類型:- 觸摸面板接口:- 輸入數/鍵:- 分辨率（位）:- 評估套件:* 數據接口:- 數據速率/采樣率 (SPS，BPS):- 電壓基準:- 電源電壓:- 電流 - 電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:16-TSSOP（0.173"，4.40mm 寬） 供應商設備封裝:16-TSSOP 包裝:帶卷 (TR) |
| AD7889ACBZ-RL | 功能描述:IC ADC 12BIT CTRLR TOUCH 12WLCSP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 觸摸屏控制器 系列:- 標準包裝:96 系列:- 類型:- 觸摸面板接口:- 輸入數/鍵:- 分辨率（位）:- 評估套件:* 數據接口:- 數據速率/采樣率 (SPS，BPS):- 電壓基準:- 電源電壓:- 電流 - 電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:16-TSSOP（0.173"，4.40mm 寬） 供應商設備封裝:16-TSSOP 包裝:帶卷 (TR) |
發布緊急采購，3分鐘左右您將得到回復。