2 × VREF p-p 27 V+ V– V+ V– GN" />
參數(shù)資料
型號： AD7294BCPZ
廠商： Analog Devices Inc
文件頁數(shù)： 16/49頁
文件大?。?/td> 0K
描述： IC ADC 12BIT I2C/SRL 1M 56LFCSP
標準包裝： 1
類型： ADC，DAC
分辨率（位）： 12 b
采樣率（每秒）： 22.22k
數(shù)據(jù)接口： I²C，串行
電壓電源： 模擬和數(shù)字
電源電壓： 4.4 V ~ 5.5 V
工作溫度： -40°C ~ 105°C
安裝類型： 表面貼裝
封裝/外殼： 56-VFQFN 裸露焊盤，CSP
供應商設備封裝： 56-LFCSP-VQ（8x8）
包裝： 托盤
AD7294
Data Sheet
Rev. H | Page 22 of 48
20k
220k
2 × VREF p-p
27
V+
V–
V+
V–
GND
2.5V
3.75V
1.25V
2.5V
3.75V
1.25V
REFOUT ADC
VIN+
AD7294
1
VIN–
440
220
0.47F
1ADDITIONAL PINS OMITTED FOR CLARITY.
220
10k
A
05747-
023
Figure 39. Dual Op Amp Circuit to Convert a Single-Ended Bipolar Signal
into a Differential Unipolar Signal
Pseudo Differential Mode
The four uncommitted analog input channels can be configured
as two pseudo differential pairs. Uncommitted input, VIN0 and
VIN1, are a pseudo differential pair, as are VIN2 and VIN3. In this
mode, VIN+ is connected to the signal source, which can have a
maximum amplitude of VREF (or 2 × VREF, depending on the
range chosen) to make use of the full dynamic range of the part.
A dc input is applied to VIN. The voltage applied to this input
provides an offset from ground or a pseudo ground for the VIN+
input. Which channel is VIN+ is determined by the ADC channel
allocation. The differential mode must be selected to operate in the
pseudo differential mode. The resulting converted pseudo differen-
tial data is stored in twos complement format in the result register.
The governing equation for the pseudo differential mode, for
VIN0 is
VOUT = 2(VIN+ VIN) VREF_ADC
where VIN+ is the single-ended signal and VIN is a dc voltage.
The benefit of pseudo differential inputs is that they separate
the analog input signal ground from the ADC ground, allowing
dc common-mode voltages to be cancelled. The typical voltage
range for VIN while in pseudo differential mode is shown in
Figure 40; Figure 41 shows a connection diagram for pseudo
differential mode.
2.0
1.5
1.0
0.5
–0.5
0
6
5
4
3
2
1
V
IN–
(V)
VREF (V)
05747-
095
AVDD = DVDD = 5V
VDRIVE = 5V
Figure 40. VIN Input Range vs. VREF in Pseudo Differential Mode
DC INPUT
VOLTAGE
VREF
p-p
REFOUT/REFIN ADC
VIN+
AD7294
1
VIN–
0.47F
1ADDITIONAL PINS OMITTED FOR CLARITY.
05747-
026
Figure 41. Pseudo Differential Mode Connection Diagram
CURRENT SENSOR
Two bidirectional high-side current sense amplifiers are
provided that can accurately amplify differential current shunt
voltages in the presence of high common-mode voltages from
AVDD up to 59.4 V. Each amplifier can accept a ±200 mV
differential input. Both current sense amplifiers have a fixed
gain of 12.5 and utilize an internal 2.5 V reference.
An analog comparator is also provided with each amplifier for
fault detection. The threshold is defined as
1.2 × Full-Scale Voltage Range
When this limit is reached, the output is latched onto a
dedicated pin. This output remains high until the latch is
cleared by writing to the appropriate register.
AD7294
AVDD TO 54.5V
RS(+)
RSENSE
ILOAD
RS(–)
R1
40k
R2
40k
R3
100k
R4
100k
Q1
Q2
VOUT
TO MUX
A1
A2
VPP
05747-
029
Figure 42. High-Side Current Sense
The AD7294 current sense comprises two main blocks: a
differential and an instrumentation amplifier. A load current
flowing through the external shunt resistor produces a voltage
at the input terminals of the AD7294. Resistors R1 and R2
connect the input terminals to the differential amplifier (A1).
A1 nulls the voltage appearing across its own input terminals
by adjusting the current through R1 and R2 with Transistor Q1
and Transistor Q2. Common-mode feedback maintains the sum
of these currents at approximately 50 μA. When the input signal
to the AD7294 is zero, the currents in R1 and R2 are equal. When
the differential signal is nonzero, the current increases through
one of the resistors and decreases in the other. The current differ-
ence is proportional to the size and polarity of the input signal.
The differential currents through Q1 and Q2 are converted into
a differential voltage by R3 and R4. A2 is configured as an instru-
mentation amplifier, buffering this voltage and providing additional
相關PDF資料
PDF描述
MS27505E17B8SC CONN RCPT 8POS BOX MNT W/SCKT
MS3114F24-61S CONN RCPT 61POS JAM NUT W/SCKT
D38999/20WH21PA CONN RCPT 21POS WALL MNT W/PINS
MS27656T23B55PA CONN RCPT 55POS WALL MNT W/PINS
D38999/26MJ43JA CONN PLUG 43POS STRAIGHT W/SCKT
相關代理商/技術參數(shù)
參數(shù)描述
AD7294BCPZRL 功能描述:IC ADC 12BIT I2C/SRL 1M 56LFCSP RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - ADCs/DAC - 專用型 系列:- 產(chǎn)品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:50 系列:- 類型:數(shù)據(jù)采集系統(tǒng)（DAS） 分辨率（位）:16 b 采樣率（每秒）:21.94k 數(shù)據(jù)接口:MICROWIRE?，QSPI?，串行，SPI? 電壓電源:模擬和數(shù)字 電源電壓:1.8 V ~ 3.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:40-WFQFN 裸露焊盤 供應商設備封裝:40-TQFN-EP（6x6） 包裝:托盤
AD7294BSUZ 功能描述:模數(shù)轉換器 - ADC 12B Monitor & Cntrl System w/ Temp Sensr RoHS:否 制造商:Analog Devices 通道數(shù)量: 結構: 轉換速率: 分辨率: 輸入類型: 信噪比: 接口類型: 工作電源電壓: 最大工作溫度: 安裝風格: 封裝 / 箱體:
AD7294BSUZRL 制造商:Analog Devices 功能描述:Temp Sensor Digital Serial (2-Wire, I2C) 64-Pin TQFP 制造商:Analog Devices 功能描述:TEMP SENSOR DGTL SERL (2-WIRE, I2C) 64TQFP - Tape and Reel 制造商:Analog Devices 功能描述:IC ADC 12BIT W/DAC/TEMP 64TQFP 制造商:Analog Devices Inc. 功能描述:Analog to Digital Converters - ADC 12-Bit Multi-Channel ADC DAC wt Temp IC 制造商:Analog Devices 功能描述:CONVERTER - ADC
AD7298 制造商:AD 制造商全稱:Analog Devices 功能描述:8-Channel, 1MSPS, 12-Bit SAR ADC with Temperature Sensor
AD7298-1BCPZ 功能描述:IC ADC 10BIT SPI/SRL 8CH 20LFCSP RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉換器 系列:- 其它有關文件:TSA1204 View All Specifications 標準包裝:1 系列:- 位數(shù):12 采樣率（每秒）:20M 數(shù)據(jù)接口:并聯(lián) 轉換器數(shù)目:2 功率耗散（最大）:155mW 電壓電源:模擬和數(shù)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(shù)目和類型:4 個單端，單極；2 個差分，單極 產(chǎn)品目錄頁面:1156 (CN2011-ZH PDF) 其它名稱:497-5435-6
發(fā)布緊急采購，3分鐘左右您將得到回復。

采購需求

(若只采購一條型號，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

*型號 *數(shù)量 廠商 批號 封裝
添加更多采購

我的聯(lián)系方式

*
*
*