参数资料
型号: AD8221BR
厂商: Analog Devices Inc
文件页数: 9/24页
文件大小: 0K
描述: IC AMP INST PREC LN 18MA 8SOIC
产品培训模块: Power Line Monitoring
Instrument Amp Primer Overview
Instrumentation Amplifiers Performance
设计资源: Low Cost, High Voltage, Programmable Gain Instrumentation Amplifier Using AD5292 and AD8221 (CN0114)
Low Cost Programmable Gain Instrumentation Amplifier Circuit Using ADG1611 and AD620 (CN0146)
标准包装: 98
放大器类型: 仪表
电路数: 1
转换速率: 2 V/µs
-3db带宽: 825kHz
电流 - 输入偏压: 200pA
电压 - 输入偏移: 25µV
电流 - 电源: 900µA
电流 - 输出 / 通道: 18mA
电压 - 电源,单路/双路(±): 4.6 V ~ 36 V,±2.3 V ~ 18 V
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 8-SOIC(0.154",3.90mm 宽)
供应商设备封装: 8-SO
包装: 管件
产品目录页面: 773 (CN2011-ZH PDF)
AD8221
Rev. C | Page 17 of 24
THEORY OF OPERATION
C1
C2
+VS
+IN
–IN
–VS
10k
10k
10k
400
400
10k
REF
OUTPUT
IB COMPENSATION
+VS
–VS
+VS
–VS
+VS
VB
I
R1
24.7k
24.7k
RG
Q1
R2
Q2
–VS
+VS
–VS
A2
A1
A3
03149-
042
Figure 43. Simplified Schematic
The AD8221 is a monolithic instrumentation amplifier based
on the classic 3-op amp topology. Input transistors Q1 and Q2
are biased at a fixed current so that any differential input signal
forces the output voltages of A1 and A2 to change accordingly.
A signal applied to the input creates a current through RG, R1,
and R2, such that the outputs of A1 and A2 deliver the correct
voltage. Topologically, Q1, A1, R1 and Q2, A2, R2 can be
viewed as precision current feedback amplifiers. The amplified
differential and common-mode signals are applied to a
difference amplifier that rejects the common-mode voltage
but amplifies the differential voltage. The difference amplifier
employs innovations that result in low output offset voltage as
well as low output offset voltage drift. Laser-trimmed resistors
allow for a highly accurate in-amp with gain error typically less
than 20 ppm and CMRR that exceeds 90 dB (G = 1).
Using superbeta input transistors and an IB compensation
scheme, the AD8221 offers extremely high input impedance,
low IB, low IB drift, low IOS, low input bias current noise, and
extremely low voltage noise of 8 nV/√Hz.
The transfer function of the AD8221 is
G
R
G
4
.
49
1+
=
Users can easily and accurately set the gain using a single
standard resistor.
Because the input amplifiers employ a current feedback
architecture, the gain-bandwidth product of the AD8221
increases with gain, resulting in a system that does not suffer
from the expected bandwidth loss of voltage feedback
architectures at higher gains.
To maintain precision even at low input levels, special attention
was given to the design and layout of the AD8221, resulting in
an in-amp whose performance satisfies the most demanding
applications.
A unique pinout enables the AD8221 to meet a CMRR
specification of 80 dB at 10 kHz (G = 1) and 110 dB at 1 kHz
(G = 1000). The balanced pinout, shown in Figure 44, reduces
the parasitics that had, in the past, adversely affected CMRR
performance. In addition, the new pinout simplifies board
layout because associated traces are grouped together. For
example, the gain setting resistor pins are adjacent to the
inputs, and the reference pin is next to the output.
8
7
6
5
1
2
3
4
–IN
RG
+VS
VOUT
REF
–VS
+IN
TOP VIEW
AD8221
03149-
043
Figure 44. Pinout Diagram
相关PDF资料
PDF描述
OP484FSZ-REEL7 IC OPAMP GP R-R 4.25MHZ 14SOIC
AD8221BRZ IC AMP INSTRUMENT PREC HP 8SOIC
OP293ESZ IC OPAMP GP 35KHZ DUAL 8SOIC
PBC12SFDN CONN HEADER .100 SINGL STR 12POS
AD8250ARMZ IC AMP INST ICMOS LDRIFT 10MSOP
相关代理商/技术参数
参数描述
AD8221BRM 制造商:Analog Devices 功能描述:SOIC IN AMP WITH FIXED GAIN OF 5 - Bulk
AD8221BRREEL 制造商:Analog Devices 功能描述:
AD8221BR-REEL 功能描述:IC AMP INST PREC LN 18MA 8SOIC RoHS:否 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:150 系列:- 放大器类型:音频 电路数:2 输出类型:- 转换速率:5 V/µs 增益带宽积:12MHz -3db带宽:- 电流 - 输入偏压:100nA 电压 - 输入偏移:500µV 电流 - 电源:6mA 电流 - 输出 / 通道:50mA 电压 - 电源,单路/双路(±):4 V ~ 32 V,±2 V ~ 16 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-TSSOP(0.173",4.40mm 宽) 供应商设备封装:8-TSSOP 包装:管件
AD8221BRREEL7 制造商:Analog Devices 功能描述:
AD8221BR-REEL7 功能描述:IC AMP INST PREC LN 18MA 8SOIC RoHS:否 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:50 系列:- 放大器类型:J-FET 电路数:2 输出类型:- 转换速率:3.5 V/µs 增益带宽积:1MHz -3db带宽:- 电流 - 输入偏压:30pA 电压 - 输入偏移:2000µV 电流 - 电源:200µA 电流 - 输出 / 通道:- 电压 - 电源,单路/双路(±):7 V ~ 36 V,±3.5 V ~ 18 V 工作温度:0°C ~ 70°C 安装类型:通孔 封装/外壳:8-DIP(0.300",7.62mm) 供应商设备封装:8-PDIP 包装:管件