- 您現在的位置：買賣IC網 > PDF目錄373922 > AD7880 (Analog Devices, Inc.) Enclosed Switches Series LS: Rod - Adjustable; 1NC 1NO DPDT Snap Action, Double Break; 0.5 in - 14NPT conduit; Plug-in PDF資料下載
參數資料
| 型號： | AD7880 |
| 廠商： | Analog Devices, Inc. |
| 英文描述： | Enclosed Switches Series LS: Rod - Adjustable; 1NC 1NO DPDT Snap Action, Double Break; 0.5 in - 14NPT conduit; Plug-in |
| 中文描述： | LC2MOS單5伏電源，低功耗，12位采樣ADC |
| 文件頁數： | 5/16頁 |
| 文件大小： | 337K |
| 代理商： | AD7880 |
AD7880
REV. 0
–5–
+
–
R
V
INA
V
INB
R
V
DAC
Figure 4. AD7880 Input Circuit
T he AD7880 accommodates three separate input ranges, 0 to
V
REF
, 0 to 2 V
REF
and
±
V
REF
. T he input configurations corre-
sponding to these ranges are shown in Figures 5, 6 and 7.
With V
REF
= V
DD
and using a nominal V
DD
of +5 V, the input
ranges are 0 V to 5 V, 0 V to 10 V and +5 V, as shown in
T able II.
T able II. Analog Input Ranges
Analog Input
Range
Input Connections
V
INA
Connection
Diagram
V
RE F
V
INB
0 V to +5 V
0 V to +10 V
±
5 V
V
DD
V
DD
V
DD
V
IN
V
IN
V
IN
V
IN
AGND
V
REF
Figure 5
Figure 6
Figure 7
+
–
R
R
SAMPLING
COMPARATOR
V
INA
V
INB
V
REF
AGND
12-BIT DAC
0 TO V
REF
V
REF
= 0 TO V
REF
V
IN
Figure 5. 0 to V
REF
Unipolar Input Configuration
+
–
R
R
SAMPLING
COMPARATOR
V
INA
V
INB
V
REF
AGND
12-BIT DAC
0 TO V
REF
V
REF
= 0 TO 2V
REF
V
IN
Figure 6. 0 to 2 V
REF
Unipolar Input Configuration
+
–
R
R
SAMPLING
COMPARATOR
V
INA
V
INB
V
REF
AGND
12-BIT DAC
0 TO V
REF
V
REF
= V
REF
±
V
IN
Figure 7.
±
V
REF
Bipolar Input Configuration
CIRCUIT INFORMAT ION
T he AD7880 is a +5 V single supply 12-bit A/D converter. T he
part requires no external components apart from a 2.5 MHz ex-
ternal clock and power supply decoupling capacitors. It contains
a 12-bit successive approximation ADC based on a fast-settling
voltage-output DAC, a high speed comparator and SAR, as well
as the necessary control logic. T he charge balancing comparator
used in the AD7880 provides the user with an inherent track-
and-hold function. T he ADC is specified to work with sampling
rates up to 66 kHz.
CONVE RT E R DE T AILS
T he AD7880 conversion cycle is initiated on the rising edge of
the CONVST pulse, as shown in the timing diagram of Figure
1. T he rising edge of the
CONVST
pulse places the track/hold
amplifier into “HOLD” mode. T he conversion cycle then takes
between 26 and 28 clock periods. T he maximum specified con-
version time is 12
μ
s. T his corresponds to a conversion cycle
time of 28 clock periods with a CLK IN frequency of 2.5 MHz
and also includes internal propagation delays. During conver-
sion the
BUSY
output will remain low, and the output databus
drivers will be three-stated. When a conversion is completed,
the
BUSY
output will go to a high level, and the result of the
conversion can be read by bringing
CS
and
RD
low.
T he track/hold amplifier acquires a 12-bit input signal in 3
μ
s.
T he overall throughput time for the AD7880 is equal to the
conversion time plus the track/hold acquisition time. For a
2.5 MHz input clock the throughput time is 15
μ
s.
RE FE RE NCE INPUT
For specified performance, it is recommended that the reference
input be tied to V
DD
. T he part, however, will operate with a ref-
erence down to 2.5 V though with reduced performance specifi-
cations. Figure 3 shows a graph of signal-to-noise ratio (SNR)
versus V
REF
.
V
REF
must not be allowed to go above V
DD
by more than
100 mV.
74
72
70
68
66
64
62
602
3
4
5
V
REF
– Volts
S
F = 51.2kHz
F = 2.525kHz
T = 25 C
Figure 3. SNR vs. V
REF
ANALOG INPUT
T he AD7880 has two analog input pins, V
INA
and V
INB
. Figure
4 shows the input circuitry to the ADC sampling comparator.
T he on-board attenuator network, made up of equal resistors,
allows for various input ranges.
相關PDF資料 |
PDF描述 |
|---|---|
| AD7880CR | LC2MOS Single +5 V Supply, Low Power, 12-Bit Sampling ADC |
| AD7880BN | LC2MOS Single +5 V Supply, Low Power, 12-Bit Sampling ADC |
| AD7880BQ | LC2MOS Single +5 V Supply, Low Power, 12-Bit Sampling ADC |
| AD7880BR | LC2MOS Single +5 V Supply, Low Power, 12-Bit Sampling ADC |
| AD7880CN | LC2MOS Single +5 V Supply, Low Power, 12-Bit Sampling ADC |
相關代理商/技術參數 |
參數描述 |
|---|---|
| AD7880BCHIPS | 功能描述:12 Bit Analog to Digital Converter 2 Input 1 SAR Die 制造商:analog devices inc. 系列:- 包裝:管件 零件狀態:上次購買時間 位數:12 采樣率（每秒）:66k 輸入數:2 輸入類型:單端 數據接口:并聯 配置:S/H-ADC 無線電 - S/H:ADC:1:1 A/D 轉換器數:1 架構:SAR 參考類型:外部，電源 電壓 - 電源，模擬:5V 電壓 - 電源，數字:5V 特性:- 工作溫度:-40°C ~ 85°C 封裝/外殼:模具 供應商器件封裝:模具 標準包裝:1 |
| AD7880BN | 功能描述:IC ADC 12BIT MONO LP 24-DIP RoHS:否 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 標準包裝:1 系列:- 位數:14 采樣率（每秒）:83k 數據接口:串行，并聯 轉換器數目:1 功率耗散（最大）:95mW 電壓電源:雙 ± 工作溫度:0°C ~ 70°C 安裝類型:通孔 封裝/外殼:28-DIP（0.600"，15.24mm） 供應商設備封裝:28-PDIP 包裝:管件 輸入數目和類型:1 個單端，雙極 |
| AD7880BNZ | 功能描述:IC ADC 12BIT MONO LOW PWR 24DIP 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 |
| AD7880BQ | 制造商:Analog Devices 功能描述:ADC Single SAR 66ksps 12-bit Parallel 24-Pin CDIP 制造商:Analog Devices 功能描述:ADC SGL SAR 66KSPS 12-BIT PARALLEL 24CDIP - Rail/Tube 制造商:Rochester Electronics LLC 功能描述:- Bulk |
| AD7880BR | 功能描述:IC ADC 12BIT LC2MOS 5V LP 24SOIC RoHS:否 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 標準包裝:1 系列:- 位數:14 采樣率（每秒）:83k 數據接口:串行，并聯 轉換器數目:1 功率耗散（最大）:95mW 電壓電源:雙 ± 工作溫度:0°C ~ 70°C 安裝類型:通孔 封裝/外殼:28-DIP（0.600"，15.24mm） 供應商設備封裝:28-PDIP 包裝:管件 輸入數目和類型:1 個單端，雙極 |
發布緊急采購，3分鐘左右您將得到回復。