- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄375265 > ADS7841PB CMOS 8-Stage Presettable 2-Decade BCD Synchronous Down Counter 16-SO -55 to 125 PDF資料下載
參數(shù)資料
| 型號： | ADS7841PB |
| 元件分類： | 通用總線功能 |
| 英文描述： | CMOS 8-Stage Presettable 2-Decade BCD Synchronous Down Counter 16-SO -55 to 125 |
| 中文描述： | 12位，4通道串行輸出采樣模擬到數(shù)字轉(zhuǎn)換器 |
| 文件頁數(shù)： | 9/14頁 |
| 文件大?。?/td> | 277K |
| 代理商： | ADS7841PB |
9
ADS7841
Converter
–
IN
+IN
CH0
CH1
CH2
CH3
COM
A2-A0
(Shown 001
B
)
SGL/DIF
(Shown HIGH)
THEORY OF OPERATION
The ADS7841 is a classic successive approximation register
(SAR) analog-to-digital (A/D) converter. The architecture is
based on capacitive redistribution which inherently includes
a sample/hold function. The converter is fabricated on a
0.6
μ
s CMOS process.
The basic operation of the ADS7841 is shown in Figure 1.
The device requires an external reference and an external
clock. It operates from a single supply of 2.7V to 5.25V. The
external reference can be any voltage between 100mV and
+V
CC
. The value of the reference voltage directly sets the
input range of the converter. The average reference input
current depends on the conversion rate of the ADS7841.
The analog input to the converter is differential and is
provided via a four-channel multiplexer. The input can be
provided in reference to a voltage on the COM pin (which
is generally ground) or differentially by using two of the four
input channels (CH0 - CH3). The particular configuration is
selectable via the digital interface.
ANALOG INPUT
Figure 2 shows a block diagram of the input multiplexer on
the ADS7841. The differential input of the converter is
derived from one of the four inputs in reference to the COM
pin or two of the four inputs. Table I and Table II show the
relationship between the A2, A1, A0, and SGL/DIF control
bits and the configuration of the analog multiplexer. The
control bits are provided serially via the DIN pin, see the
Digital Interface section of this data sheet for more details.
When the converter enters the hold mode, the voltage
difference between the +IN and –IN inputs (see Figure 2) is
captured on the internal capacitor array. The voltage on the
–IN input is limited between –0.2V and 1.25V, allowing the
input to reject small signals which are common to both the
+IN and –IN input. The +IN input has a range of –0.2V to
+V
CC
+ 0.2V.
FIGURE 2. Simplified Diagram of the Analog Input.
A2
A1
A0
CH0
CH1
CH2
CH3
COM
0
1
0
1
0
0
1
1
1
1
0
0
+IN
–IN
–IN
+IN
+IN
–IN
–IN
+IN
TABLE II. Differential Channel Control (SGL/DIF LOW).
A2
A1
A0
CH0
CH1
CH2
CH3
COM
0
1
0
1
0
0
1
1
1
1
0
0
+IN
–IN
–IN
–IN
–IN
+IN
+IN
+IN
TABLE I. Single-Ended Channel Selection (SGL/DIF HIGH).
The input current on the analog inputs depends on the
conversion rate of the device. During the sample period, the
source must charge the internal sampling capacitor (typi-
cally 25pF). After the capacitor has been fully charged, there
is no further input current. The rate of charge transfer from
the analog source to the converter is a function of conver-
sion rate.
FIGURE 1. Basic Operation of the ADS7841.
+V
CC
CH0
CH1
CH2
CH3
COM
SHDN
V
REF
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
DCLK
CS
DIN
BUSY
DOUT
MODE
GND
+V
CC
Serial/Conversion Clock
Chip Select
Serial Data In
Serial Data Out
0.1μF
0.1μF
+2.7V to +5V
ADS7841
Single-ended
or differential
analog inputs
+
1μF
to
10μF
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| ADS7842 | CMOS 8-Stage Presettable 2-Decade BCD Synchronous Down Counter 16-SO -55 to 125 |
| ADS7842E | 12-Bit, 4-Channel Parallel Output Sampling ANALOG-TO-DIGITAL CONVERTER |
| ADS7842EB | CMOS 8-Stage Presettable 2-Decade BCD Synchronous Down Counter 16-TSSOP -55 to 125 |
| ADS7843 | CMOS 8-Stage Presettable 2-Decade BCD Synchronous Down Counter 16-TSSOP -55 to 125 |
| ADS7843E | CMOS 8-Stage Presettable 8-Bit Binary Synchronous Down Counter 16-PDIP -55 to 125 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| ADS7841PB | 制造商:Texas Instruments 功能描述:IC 12BIT ADC 7841 PDIP16 |
| ADS7841PBG4 | 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 12B 4-Ch Serial Output Sampling 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 |
| ADS7841PG4 | 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 12-Bit 4-Ch Serial Output Sampling 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 |
| ADS7841-Q1 | 制造商:TI 制造商全稱:Texas Instruments 功能描述:12-BIT 4-CHANNEL SERIAL-OUTPUT SAMPLING ANALOG-TO-DIGITAL CONVERTER |
| ads7841qdbqrrb | 制造商:Texas Instruments 功能描述:A/D CONV 12-BIT 4-CHANNEL 16LD |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。