AD8221BR Analog Devices Inc, AD8221BR Datasheet - Page 18
![IC AMP INST PREC LN 18MA 8SOIC](/photos/5/66/56684/505-8-soic_sml.jpg)
AD8221BR
Manufacturer Part Number
AD8221BR
Description
IC AMP INST PREC LN 18MA 8SOIC
Manufacturer
Analog Devices Inc
Type
Instrumentation Ampr
Specifications of AD8221BR
Rohs Status
RoHS non-compliant
Design Resources
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)
Amplifier Type
Instrumentation
Number Of Circuits
1
Slew Rate
2 V/µs
-3db Bandwidth
825kHz
Current - Input Bias
200pA
Voltage - Input Offset
25µV
Current - Supply
900µA
Current - Output / Channel
18mA
Voltage - Supply, Single/dual (±)
4.6 V ~ 36 V, ±2.3 V ~ 18 V
Operating Temperature
-40°C ~ 85°C
Mounting Type
Surface Mount
Package / Case
8-SOIC (3.9mm Width)
Number Of Channels
1
Number Of Elements
1
Power Supply Requirement
Dual
Common Mode Rejection Ratio
140dB
Voltage Gain Db
60dB
Input Resistance
100000@±15VMohm
Input Offset Voltage
0.025@±15VmV
Input Bias Current
0.0004@±15VnA
Single Supply Voltage (typ)
Not RequiredV
Power Supply Rejection Ratio
140dB
Power Dissipation
200mW
Rail/rail I/o Type
No
Single Supply Voltage (min)
Not RequiredV
Single Supply Voltage (max)
Not RequiredV
Dual Supply Voltage (min)
±2.3V
Dual Supply Voltage (max)
±18V
Operating Temp Range
-40C to 125C
Operating Temperature Classification
Automotive
Mounting
Surface Mount
Pin Count
8
Package Type
SOIC N
No. Of Amplifiers
1
Gain Db Min
1dB
Bandwidth
825kHz
Amplifier Output
Single Ended
Cmrr
140dB
Supply Voltage Range
± 2.3V To ± 18V
Rohs Compliant
No
Output Type
-
Gain Bandwidth Product
-
Lead Free Status / RoHS Status
Not Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
AD8221BR
Manufacturer:
ADI/亚德诺
Quantity:
20 000
Company:
Part Number:
AD8221BRZ
Manufacturer:
AD
Quantity:
21 880
Part Number:
AD8221BRZ
Manufacturer:
ADI/亚德诺
Quantity:
20 000
Company:
Part Number:
AD8221BRZ-R7
Manufacturer:
AD
Quantity:
1 149
AD8221
REFERENCE TERMINAL
As shown in Figure 42, the reference terminal, REF, is at one
end of a 10 kΩ resistor. The output of the instrumentation
amplifier is referenced to the voltage on the REF terminal; this
is useful when the output signal needs to be offset to a precise
midsupply level. For example, a voltage source can be tied to the
REF pin to level-shift the output so that the AD8221 can interface
with an ADC. The allowable reference voltage range is a function
of the gain, input, and supply voltage. The REF pin should not
exceed either +V
For best performance, source impedance to the REF terminal
should be kept low, because parasitic resistance can adversely
affect CMRR and gain accuracy.
POWER SUPPLY REGULATION AND BYPASSING
A stable dc voltage should be used to power the instrumentation
amplifier. Noise on the supply pins can adversely affect
performance. Bypass capacitors should be used to decouple
the amplifier.
A 0.1 μF capacitor should be placed close to each supply pin.
As shown in Figure 46, a 10 μF tantalum capacitor can be used
further away from the part. In most cases, it can be shared by
other precision integrated circuits.
INPUT BIAS CURRENT RETURN PATH
The input bias current of the AD8221 must have a return path
to common. When the source, such as a thermocouple, cannot
provide a return current path, one should be created, as shown
in Figure 47.
Figure 46. Supply Decoupling, REF, and Output Referred to Local Ground
S
or –V
+IN
–IN
S
by more than 0.5 V.
AD8221
+V
–V
S
S
0.1µF
0.1µF
REF
10µF
10µF
LOAD
V
OUT
Rev. B | Page 18 of 24
INPUT PROTECTION
All terminals of the AD8221 are protected against ESD, 1 kV
Human Body Model. In addition, the input structure allows for
dc overload conditions below the negative supply, −V
internal 400 Ω resistors limit current in the event of a negative
fault condition. However, in the case of a dc overload voltage
above the positive supply, +V
through the ESD diode to the positive rail. Therefore, an external
resistor should be used in series with the input to limit current
for voltages above +Vs. In either scenario, the AD8221 can
safely handle a continuous 6 mA current, I = V
positive overvoltage and I = V
overvoltage.
For applications where the AD8221 encounters extreme
overload voltages, as in cardiac defibrillators, external series
resistors, and low leakage diode clamps, such as BAV199Ls,
FJH1100s, or SP720s should be used.
f
HIGH-PASS
Figure 47. Creating an I
=
2πRC
1
TRANSFORMER
THERMOCOUPLE
C
C
CAPACITOR COUPLED
S
, a large current flows directly
IN
R
R
/(400 Ω + R
AD8221
AD8221
AD8221
BIAS
+V
–V
+V
–V
+V
–V
Path
S
S
S
S
S
S
EXT
) for negative
REF
REF
REF
IN
/R
EXT
S
. The
for