- 您現在的位置：買賣IC網 > PDF目錄373916 > AD7777AR (ANALOG DEVICES INC) LC2MOS, High Speed 1-, 4- & 8-Channel 10-Bit ADCs PDF資料下載
參數資料
| 型號： | AD7777AR |
| 廠商： | ANALOG DEVICES INC |
| 元件分類： | ADC |
| 英文描述： | LC2MOS, High Speed 1-, 4- & 8-Channel 10-Bit ADCs |
| 中文描述： | 4-CH 10-BIT PROPRIETARY METHOD ADC, PARALLEL ACCESS, PDSO28 |
| 封裝： | MS-013AE, SOIC-28 |
| 文件頁數： | 6/12頁 |
| 文件大小： | 220K |
| 代理商： | AD7777AR |
AD7776/AD7777/AD7778
–6–
REV. 0
CR6:
Determines whether operation is on a single channel or
simultaneous sampling on two channels. Location CR6 is a
“don’t care” for the AD7776.
C R6
0
Function
Single channel operation. Channel select
address is contained in locations CR0–CR2.
T wo channels simultaneously sampled
and sequentially converted. Channel
select addresses contained in locations
CR0–CR2 and CR3–CR5.
CR7:
Determines whether the device is in the normal operating
mode or in the half-scale test mode.
1
C R7
0
1
Function
Normal Operating Mode
Half-Scale T est Mode
In the half-scale test mode REFIN is internally connected as an
analog input(s). In this mode locations CR0–CR2 and CR3–
CR5 are all “don’t cares” since it is REFIN which will be con-
verted. For the AD7777 and AD7778, the contents of location
CR6 still determine whether a single or a double conversion is
carried out on the REFIN level.
CR8:
Determines whether the device is in the normal operating
mode or in the powerdown mode.
C R8
0
1
Function
Normal Operating Mode
Powerdown Mode
In the powerdown mode all linear circuitry is turned off and the
REFOUT output is weakly (5 k
) pulled to AGND. T he input
impedance of the analog inputs and of the REFIN input re-
mains the same in either normal mode or powerdown mode. See
under Circuit Description—Powerdown Mode.
CR9:
Determines whether
BUSY
/
INT
output flag goes low and
remains low during conversion(s) or else goes low and remains
low after the conversion(s) is (are) complete.
C R9
0
BUSY/INT
Functionality
Output goes low and remains low during
conversion(s).
Output goes low and remains low after conversion(s)
is (are) complete.
1
ADC Conversion Start T iming
Figure 6 shows the operating waveforms for the start of a con-
version cycle. On the rising edge of
WR
, the conversion cycle
starts with the acquisition and tracking of the selected ADC
channel, A
IN
1–8. T he analog input voltage is held 40 ns (typi-
cally) after the first rising edge of CLK IN following four com-
plete CLK IN cycles. If t
D
in Figure 6 is greater than 12 ns, the
falling edge of CLK IN as shown will be seen as the first falling
clock edge. If t
D
is less than 12 ns, the first falling clock edge to
be recognized will not occur until one cycle later.
Following the “hold” on the analog input(s), two complete
CLK IN cycles are allowed for settling purposes before the MSB
decision is made. T he actual decision point occurs approximately
40 ns after the rising edge of CLK IN as shown in Figure 6. A
further two CL K IN cycles are allowed for the second MSB
decision. T he succeeding bit decisions are made approximately
40 ns after each rising edge of CLK IN until the conversion is
complete. At the end of conversion, if a single conversion
has been requested (CR6 = 0), the
BUSY
/
INT
line changes
CONT ROL RE GIST E R
T he control register is 10-bits wide and can only be written to.
On power-on, all locations in the control register are automati-
cally loaded with 0s. For the single channel AD7776, locations
CR0 to CR6 of the control register are “don’t cares.” For the
quad channel AD7777, locations CR2 and CR5 are “don’t
cares.” Individual bit functions are described below.
CR0–CR2:
Channel Address Locations. Determines which channel
will be selected and converted for single channel operation. For si-
multaneous sampling operation CR0–CR2 holds the address of one
of the two channels to be sampled.
AD7776
C R2 C R1
X *
*X = Don’t Care
C R0
X
Function
Select A
IN
1
X
AD7777
CR2 CR1
X *
X
X
X
*X = Don’t Care
CR0
0
1
0
1
Function
Select A
IN
1
Select A
IN
2
Select A
IN
3
Select A
IN
4
0
0
1
1
AD7778
CR2 CR1
0
0
0
0
1
1
1
1
CR0 Function
0
Select A
IN
1
1
Select A
IN
2
0
Select A
IN
3
1
Select A
IN
4
0
Select A
IN
5
1
Select A
IN
6
0
Select A
IN
7
1
Select A
IN
8
0
0
1
1
0
0
1
1
CR3–CR5:
Channel Address Locations. Only applicable for simul-
taneous sampling with the AD7777 or AD7778 when CR3–CR5
holds the address of the second channel to be sampled.
AD7777
CR5 CR4
X *
X
X
X
*X = Don’t Care
CR3 Function
0
Select A
IN
1
1
Select A
IN
2
0
Select A
IN
3
1
Select A
IN
4
0
0
1
1
AD7778
CR5 CR4
0
0
0
0
1
1
1
1
CR3
0
1
0
1
0
1
0
1
Function
Select A
IN
1
Select A
IN
2
Select A
IN
3
Select A
IN
4
Select A
IN
5
Select A
IN
6
Select A
IN
7
Select A
IN
8
0
0
1
1
0
0
1
1
相關PDF資料 |
PDF描述 |
|---|---|
| AD7778 | LC2MOS, High Speed 1-, 4- & 8-Channel 10-Bit ADCs |
| AD7778AS | LC2MOS, High Speed 1-, 4- & 8-Channel 10-Bit ADCs |
| AD7778* | LC2MOS. High Speed 1-. 4- & 8-Channel 10-Bit ADCs |
| AD7782 | Read Only, Pin Configured 24-Bit ADC |
| AD7782BRU | Read Only, Pin Configured 24-Bit ADC |
相關代理商/技術參數 |
參數描述 |
|---|---|
| AD7777AR-REEL | 制造商:Analog Devices 功能描述:ADC Single SAR 378ksps 10-bit Parallel 28-Pin SOIC W T/R |
| AD7777ARZ | 功能描述:IC ADC 10BIT 4CH HS 28SOIC RoHS:是 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 其它有關文件:TSA1204 View All Specifications 標準包裝:1 系列:- 位數:12 采樣率（每秒）:20M 數據接口:并聯 轉換器數目:2 功率耗散（最大）:155mW 電壓電源:模擬和數字 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-TQFP 供應商設備封裝:48-TQFP（7x7） 包裝:Digi-Reel® 輸入數目和類型:4 個單端，單極；2 個差分，單極 產品目錄頁面:1156 (CN2011-ZH PDF) 其它名稱:497-5435-6 |
| AD7777ARZ-REEL | 功能描述:IC ADC 10BIT 4CHAN HS 28SOIC RoHS:是 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 標準包裝:1,000 系列:- 位數:12 采樣率（每秒）:300k 數據接口:并聯 轉換器數目:1 功率耗散（最大）:75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC（0.295"，7.50mm 寬） 供應商設備封裝:24-SOIC 包裝:帶卷 (TR) 輸入數目和類型:1 個單端，單極；1 個單端，雙極 |
| AD7778 | 制造商:AD 制造商全稱:Analog Devices 功能描述:LC2MOS, High Speed 1-, 4- & 8-Channel 10-Bit ADCs |
發布緊急采購，3分鐘左右您將得到回復。