參數(shù)資料
型號: AD621A
廠商: Analog Devices, Inc.
元件分類: 運(yùn)動(dòng)控制電子
英文描述: Low Drift, Low Power Instrumentation Amplifier
中文描述: 低漂移,低功耗儀表放大器
文件頁數(shù): 11/16頁
文件大?。?/td> 663K
代理商: AD621A
AD621
REV. A
–11–
3k‰
+5V
DIGITAL
DATA
OUTPUT
ADC
REF
IN
AGND
20k‰
10k‰
20k‰
AD621B
1.7mA
1.3mA
MAX
0.10mA
0.6mA
MAX
3k‰
3k‰
3k‰
4
AD705
2
1
8
3
7
6
5
Figure 31. A Pressure Monitor Circuit which Operates on a +5 V Power Supply
Pressure Measurement
Although useful in many bridge applications such as weigh-
scales, the AD621 is especially suited for higher resistance pres-
sure sensors powered at lower voltages where small size and low
power become more even significant.
Figure 31 shows a 3 k
pressure transducer bridge powered
from +5 V. In such a circuit, the bridge consumes only 1.7 mA.
Adding the AD621
and a buffered voltage divider allows the sig-
nal to be conditioned for only 3.8 mA of total supply current.
Small size and low cost make the AD621 especially attractive for
voltage output pressure transducers. Since it delivers low noise
and drift, it will also serve applications such as diagnostic
noninvasion blood pressure measurement.
Wide Dynamic Range Gain Block Suppresses Large Common-
Mode and Offset Signals
The AD621 is especially useful in wide dynamic range applica-
tions such as those requiring the amplification of signals in the
presence of large, unwanted common-mode signals or offsets.
Many monolithic in amps achieve low total input drift and noise
errors only at relatively high gains (~100). In contrast the
AD621’s low output errors allow such performance at a gain of
10, thus allowing larger input signals and therefore greater
dynamic range. The circuit of Figure 32 (
±
15 V supply, G = 10)
has only 2.5
μ
V/
°
C max. V
OS
drift and 0.55
μ
/V p-p typical
0.1 Hz to 10 Hz noise, yet will amplify a
±
0.5 V differential sig-
nal while suppressing a
±
10 V common-mode signal, or it will
amplify a
±
1.25 V differential signal while suppressing a 1 V
offset by use of the DAC driving the reference pin of the
AD621. An added benefit, the offsetting DAC connected to the
reference pin allows removal of a dc signal without the associ-
ated time-constant of ac coupling. Note the representations of a
differential and common-mode signal shown in Figure 32 such
that a single-ended (or normal mode) signal of +1 V would be
composed of a +0.5 V common-mode component and a +1 V
differential component.
Table I. Make vs. Buy Error Budget
AD621 Circuit
Calculation
Discrete Circuit
Calculation
Error, ppm of Full Scale
AD621
Error Source
Discrete
ABSOLUTE ACCURACY at T
A
= +25
°
C
Input Offset Voltage,
μ
V
Output Offset Voltage,
μ
V
Input Offset Current, nA
CMR, dB
125
μ
V/20 mV
N/A
2 nA
×
350
/20 mV
110 dB
3.16 ppm,
×
5 V/20 mV
(150
μ
V
×
2
/20 mV
((150
μ
V
×
2)/100)/20 mV
(6 nA
×
350
)/20 mV
(0.02% Match
×
5 V)/20 mV
1
6,250
N/A
12,1
18
12,
791
15,000
12,
150
121,
53
1
4,988
Total Absolute Error
1
7,558
20,191
DRIFT TO +85
°
C
Gain Drift, ppm/
°
C
Input Offset Voltage Drift,
μ
V/
°
C
Output Offset Voltage Drift,
μ
V/
°
C
5 ppm
×
60
°
C
1
μ
V/
°
C
×
60
°
C/20 mV
N/A
100 ppm/
°
C Track
×
60
°
C
(2.5
μ
V/
°
C
×
2
×
60
°
C)/20 mV
(2.5
μ
V/
°
C
×
2
×
60
°
C)/100/20 mV
13,
300
1
3,000
N/A
12,
600
15,000
12,
150
Total Drift Error
1
3,690
15,750
RESOLUTION
Gain Nonlinearity, ppm of Full Scale
Typ 0.1 Hz–10 Hz Voltage Noise,
μ
V p-p 0.28
μ
V p-p/20 mV
40 ppm
40 ppm
(0.38
μ
V p-p
×
2
)120 mV
12,1
40
121,
14
12,1
40
12,1
27
Total Resolution Error
121,
54
121,
67
Grand Total Error
11,472
36,008
G = 100, V
S
=
±
15 V.
(All errors are min/max and referred to input.)
相關(guān)PDF資料
PDF描述
AD621AN Low Drift, Low Power Instrumentation Amplifier
AD621AR Low Drift, Low Power Instrumentation Amplifier
AD621B RE Series - Econoline Unregulated DC-DC Converters; Input Voltage (Vdc): 3.3V; Output Voltage (Vdc): 3.3V; Power: 1W; Industry Standard Pinout; 1kVDC & 2kVDC Isolation; UL94V-0 Package Material; Optional Continuous Short Circuit Protected; Fully Encapsulated; Custom Solutions Available; Efficiency to 85%
AD621BN Low Drift, Low Power Instrumentation Amplifier
AD621BR Low Drift, Low Power Instrumentation Amplifier
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AD621ACHIPS 制造商:AD 制造商全稱:Analog Devices 功能描述:Low Drift, Low Power Instrumentation Amplifier
AD621AN 制造商:Analog Devices 功能描述:SP Amp INSTR Amp Single 制造商:Analog Devices 功能描述:IC AMP INSTRUMENTATION DIP8 621
AD621ANZ 功能描述:IC AMP INST LDRIFT LP 18MA 8DIP RoHS:是 類別:集成電路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 放大器類型:通用 電路數(shù):4 輸出類型:- 轉(zhuǎn)換速率:0.6 V/µs 增益帶寬積:1MHz -3db帶寬:- 電流 - 輸入偏壓:45nA 電壓 - 輸入偏移:2000µV 電流 - 電源:1.4mA 電流 - 輸出 / 通道:40mA 電壓 - 電源,單路/雙路(±):3 V ~ 32 V,±1.5 V ~ 16 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:14-TSSOP(0.173",4.40mm 寬) 供應(yīng)商設(shè)備封裝:14-TSSOP 包裝:帶卷 (TR) 其它名稱:LM324ADTBR2G-NDLM324ADTBR2GOSTR
AD621AR 功能描述:IC AMP INST LDRIFT LP 18MA 8SOIC RoHS:否 類別:集成電路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:Excalibur™ 放大器類型:J-FET 電路數(shù):1 輸出類型:- 轉(zhuǎn)換速率:45 V/µs 增益帶寬積:10MHz -3db帶寬:- 電流 - 輸入偏壓:20pA 電壓 - 輸入偏移:490µV 電流 - 電源:1.7mA 電流 - 輸出 / 通道:48mA 電壓 - 電源,單路/雙路(±):4.5 V ~ 38 V,±2.25 V ~ 19 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:8-SOIC(0.154",3.90mm 寬) 供應(yīng)商設(shè)備封裝:8-SOIC 包裝:帶卷 (TR)
AD621AR-REEL 制造商:Analog Devices 功能描述:SP Amp INSTR Amp Single 制造商:Rochester Electronics LLC 功能描述:LOW DRIFT LOW POWER INAMP - Tape and Reel