- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄378284 > ADC12038CIWM (NATIONAL SEMICONDUCTOR CORP) Self-Calibrating 12-Bit Plus Sign Serial I/O A/D Converters with MUX and Sample/Hold PDF資料下載
參數(shù)資料
| 型號： | ADC12038CIWM |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類： | ADC |
| 英文描述： | Self-Calibrating 12-Bit Plus Sign Serial I/O A/D Converters with MUX and Sample/Hold |
| 中文描述： | 8-CH 12-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, PDSO28 |
| 封裝： | SOP-28 |
| 文件頁數(shù)： | 34/41頁 |
| 文件大?。?/td> | 1036K |
| 代理商： | ADC12038CIWM |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁當(dāng)前第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁
Application Hints
(Continued)
TheADC 12030/2/4/8 can be used in either ratiometric or ab-
solute reference applications. In ratiometric systems, the
analog input voltage is proportional to the voltage used for
the ADC’s reference voltage. When this voltage is the sys-
tem power supply, the V
REF+
pin is connected to V
A+
and
V
REF
is connected to ground. This technique relaxes the
system reference stability requirements because the analog
input voltage and the ADC reference voltage move together.
This maintains the same output code for given input condi-
tions. For absolute accuracy, where the analog input voltage
varies between very specific voltage limits, a time and tem-
perature stable voltage source can be connected to the ref-
erence inputs. Typically, the reference voltage’s magnitude
will require an initial adjustment to null reference voltage in-
duced full-scale errors.
Below are recommended references along with some key
specifications.
Output
Voltage
Tolerance
±
0.5%
±
0.1%
Adjustable
Temperature
Coefficient
Part Number
LM4041CI-Adj
LM4040AI-4.1
Circuit of
Figure 16
The reference voltage inputs are not fully differential. The
ADC12030/2/4/8 will not generate correct conversions or
comparisons if V
REF+
is taken below V
REF
. Correct conver-
sions result when V
REF+
and V
REF
differ by 1V and remain,
at all times, between ground and V
A+
. The V
common
mode range, (V
REF+
+ V
REF
)/2 is restricted to (0.1 x V
A+
) to
(0.6 x V
A+
). Therefore, with V
A+
= 5V the center of the refer-
ence ladder should not go below 0.5V or above 3.0V. Figure
17 is a graphic representation of the voltage restrictions on
V
REF+
and V
REF
.
±
100ppm/C
±
100ppm/C
±
2ppm/C
4.0 ANALOG INPUT VOLTAGE RANGE
The ADC12030/2/4/8’s fully differential ADC generate a
two’s complement output that is found by using the equa-
tions shown below:
for (12-bit) resolution the Output Code =
for (8-bit) resolution the Output Code =
Round off to the nearest integer value between 4096 to
4095 for 12-bit resolution and between 256 to 255 for 8-bit
resolution if the result of the above equation is not a whole
number.
Examples are shown in the table below:
Digital
Output
Code
V
REF+
V
REF
V
IN+
V
IN
+2.5V
+4.096V
+4.096V
+4.096V
+1V
0V
0V
0V
+1.5V
+3V
+2.499V
0V
0V
0V
0,1111,1111,1111
0,1011,1011,1000
1,1111,1111,1111
1,0000,0000,0000
+2.500V
+4.096V
5.0 INPUT CURRENT
At the start of the acquisition window (t
) a charging current
flows into or out of the analog input pins (A/DIN1 and
A/DIN2) depending on the input voltage polarity. The analog
input pins are CH0–CH7 and COM when A/DIN1 is tied to
MUXOUT1 andA/DIN2 is tied to MUXOUT2. The peak value
of this input current will depend on the actual input voltage
applied, the source impedance and the internal multiplexer
switch on resistance. With MUXOUT1 tied to A/DIN1 and
DS011354-42
*
Tantalum
FIGURE 16. Low Drift Extremely
Stable Reference Circuit
DS011354-45
FIGURE 17. V
REF
Operating Range
www.national.com
34
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| ADC12030CIWM | Self-Calibrating 12-Bit Plus Sign Serial I/O A/D Converters with MUX and Sample/Hold |
| ADC12032CIWM | Self-Calibrating 12-Bit Plus Sign Serial I/O A/D Converters with MUX and Sample/Hold |
| ADC12L030 | 3.3V Self-Calibrating 12-Bit Plus Sign Serial I/O A/D Converters with MUX and Sample/Hold(可自行校對3.3V12位串行輸入/輸出帶MUX，采樣/保持功能A/D轉(zhuǎn)換器) |
| ADC12L034 | 3.3V Self-Calibrating 12-Bit Plus Sign Serial I/O A/D Converters with MUX and Sample/Hold(可自行校對3.3V12位串行輸入/輸出帶MUX，采樣/保持功能A/D轉(zhuǎn)換器) |
| ADC12L038 | 3.3V Self-Calibrating 12-Bit Plus Sign Serial I/O A/D Converters with MUX and Sample/Hold(可自行校對3.3V12位串行輸入/輸出帶MUX，采樣/保持功能A/D轉(zhuǎn)換器) |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| ADC12038CIWM/NOPB | 功能描述:模數(shù)轉(zhuǎn)換器 - ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32 |
| ADC12038CIWM/NOPB | 制造商:Texas Instruments 功能描述:A/D Converter (A-D) IC |
| ADC12038CIWMNOPB | 制造商:National Semiconductor 功能描述:ADC Single SAR 114ksps 12-bit+Sign Serial 28-Pin SOIC W Rail 制造商:National Semiconductor 功能描述:ADC Single SAR 114ksps 12-bit+Sign Serial 28-Pin SOIC Rail |
| ADC12038CIWMX | 功能描述:模數(shù)轉(zhuǎn)換器 - ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32 |
| ADC12038CIWMX/NOPB | 功能描述:模數(shù)轉(zhuǎn)換器 - ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。