Preliminary Technical Data
40 μA Micropower Instrumentation
Amplifier in WLCSP Package
AD8235
FEATURES
BALL CONFIGURATION
Low power
40 μA supply current (max)
6 nA shutdown current
Space-saving 1.6mm X2mm WLCSP package
Low input currents
1 pA input bias current
0.5 pA input offset current
High CMRR
110 dB CMRR, G = 100
Zero input cross-over distortion
Rail-to-rail input and output
Gain set with single resistor
Medical instrumentation
Low side current sense
Portable devices
A2
SDN
A3
-IN
B1
OUT
B2
NC
B3
RG
D1
-VS
D3
+IN
D2
NC
(Top View - bumps
face down)
+Vs
SDN
-IN
OUT
NC
RG
REF
Ball is not present
RG
-Vs
NC
+IN
Pin Identifier
A1
A2
A3
B1
B2
B3
C1
C2
C3
D1
D2
D3
C3
RG
C1
REF
(Top View)
Figure 1.
5
Input Common-Mode Voltage (V)
APPLICATIONS
A1
+VS
4.5
4
G=5
Vs = 5V
Vref = 2.5V
3.5
3
2.5
2
1.5
G=5
Vs = 1.8V
Vref = 0.9V
1
0.5
0
-0.5
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
Output Voltage (V)
Figure 2. Wide Common-Mode Voltage Range vs.
Output Voltage
GENERAL DESCRIPTION
The AD8235 is the world’s smallest and world’s lowest power
instrumentation amplifier. It has rail-to-rail outputs and can
operate on voltages as low as 1.8 V. Its 40 μA maximum supply
current and 6nA maximum supply current in shutdown makes
it an excellent choice in battery-powered applications.
The AD8235 is an excellent choice for signal conditioning. Its low
input bias current of 1 pA and high CMRR of 110 dB (G = 100)
offer tremendous value for its size and low power. It has a wider
common-mode voltage range than typical three-op-amp
instrumentation amplifiers, making this a great solution for
applications that operate on a single 1.8 V or 3 V supply. An
innovative input stage allows for a wide rail-to-rail input voltage
range without the cross-over distortion common in other
designs.
The AD8235 is available in a wafer level chip scale package and
is specified over the industrial temperature range of −40°C to
+125°C.
General
Purpose
AD8220
AD8221
AD8222
AD8220
AD8228
AD8295
Zero
Drift
AD8230
AD8231
AD8290
AD8293G80
AD8293G160
AD8553
AD8556
AD8557
Military
Grade
AD620
AD621
AD624
AD524
AD526
Low
Power
AD8235
AD627
AD623
AD8223
AD8226
High Speed
PGA
AD8250
AD8251
AD8253
Rev. PrA
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
©2009 Analog Devices, Inc. All rights reserved.
AD8235
Preliminary Technical Data
SPECIFICATIONS
+VS = 5 V, −VS = 0 V (GND), VREF = 2.5 V, TA = 25°C, G = 5, RL = 100 kΩ to GND, unless otherwise noted.
Table 1.
Parameter
COMMON-MODE REJECTION RATIO (CMRR)
CMRR DC
G=5
G = 10
G = 100
G = 200
NOISE
Voltage Noise Spectral Density, RTI
RTI, 0.1 Hz to 10 Hz
G=5
G = 200
Current Noise
VOLTAGE OFFSET
Input Offset, VOS
Average TC
Offset RTI vs. Supply (PSR)
G=5
G = 10
G = 100
G = 200
INPUT CURRENT
Input Bias Current
Over Temperature
Input Offset Current
Over Temperature
DYNAMIC RESPONSE
–3 dB Small Signal Bandwidth
G=5
G = 10
G = 100
G = 200
Settling Time 0.01%
G=5
G = 10
G = 100
G = 200
Slew Rate
G = 5 to 100
GAIN
Gain Range
Gain Error
G=5
G = 10
G = 100
Test Conditions
Min
Typ
86
90
100
100
94
100
110
110
dB
dB
dB
dB
76
nV/√Hz
4
4
15
μV p-p
μV p-p
fA/√Hz
1kHz, G = 5
Max
3.5
Unit
2.5
mV
μV/°C
120
126
130
130
dB
dB
dB
dB
Vs = 1.8V to 5V
100
110
110
110
1
−40°C to +85°C
−40°C to +125°C
0.5
−40°C to +85°C
−40°C to +125°C
10
100
600
5
50
130
pA
pA
pA
pA
pA
pA
23
9
0.8
0.4
kHz
kHz
kHz
kHz
444
456
992
1816
μs
μs
μs
μs
9
mV/μs
Vout = 4V Step
G = 5 + 420 kΩ/RG
5
0.005
0.03
0.06
Rev. PrA | Page 2 of 6
2001
V/V
0.05
0.2
0.2
%
%
%
Preliminary Technical Data
Parameter
G =200
Nonlinearity
G=5
G = 10
G = 100
G = 200
Gain vs. Temperature
G=5
G > 10
INPUT
Differential Impedance
Common Mode Impedance
Input Voltage Range
OUTPUT
Output Voltage High, VOH
Output Voltage Low, VOL
Short-Circuit Limit, ISC
REFERENCE INPUT
RIN
IIN
Voltage Range
Gain to Output
POWER SUPPLY
Operating Range
Quiescent Current
Over Temperature
TEMPERATURE RANGE
For Specified Performance
1
AD8235
Test Conditions
Min
Typ
0.15
Max
0.3
Unit
%
RL = 10 kΩ or 100 kΩ
RL = 10 kΩ or 100 kΩ
RL = 10 kΩ or 100 kΩ
RL = 10 kΩ or 100 kΩ
2
1.2
0.5
0.5
10
10
10
10
ppm
ppm
ppm
ppm
−40°C to +125°C
−40°C to +125°C
0.25
1
-50
ppm/°C
ppm/°C
+VS
GΩ||pF
GΩ||pF
V
440||1.6
110||6.2
−40°C to +125°C
0
RL = 100 kΩ to GND
−40°C to +125°C
RL = 10 kΩ to GND
−40°C to +125°C
RL = 100 kΩ to GND
−40°C to +125°C
RL = 10 kΩ to GND
−40°C to +125°C
4.98
4.98
4.9
4.99
V
V
4.95
2
10
5
5
25
30
±55
−IN, +IN = 0 V
210
20
−VS
+VS
1
1.8
30
−40
The AD8235 was designed for low to mid-range gains. Gains can certainly be set beyond 200.
Rev. PrA | Page 3 of 6
V
mV
mV
mV
mV
mA
kΩ
nA
V
V/V
5.5
40
50
V
μA
μA
+125
°C
AD8235
Preliminary Technical Data
+VS = 1.8 V, −VS = 0 V (GND), VREF = 0.9 V, TA = 25°C, G = 5, RL = 100 kΩ to GND, unless otherwise noted.
Table 2.
Parameter
COMMON-MODE REJECTION RATIO (CMRR)
CMRR DC
G=5
G = 10
G = 100
G = 200
NOISE
Voltage Noise Spectral Density, RTI
RTI, 0.1 Hz to 10 Hz
G=5
G = 200
Current Noise
VOLTAGE OFFSET
Input Offset, VOS
Average TC
Offset RTI vs. Supply (PSR)
G=5
G = 10
G = 100
G = 200
INPUT CURRENT
Input Bias Current
Over Temperature
Input Offset Current
Over Temperature
DYNAMIC RESPONSE
–3 dB Small Signal Bandwidth
G=5
G = 10
G = 100
G = 200
Settling Time 0.01%
G=5
G = 10
G = 100
G = 200
Slew Rate
G = 5 to 100
GAIN
Gain Range
Gain Error
G=5
G = 10
G = 100
1
Test Conditions
Min
Typ
86
90
100
100
94
100
110
110
dB
dB
dB
dB
76
nV/√Hz
4
4
15
μV p-p
μV p-p
fA/√Hz
5
10
mV
μV/°C
120
126
130
130
dB
dB
dB
dB
1kHz, G = 5
Max
Unit
Vs = 1.8V to 5V
100
110
110
110
1
−40°C to +85°C
−40°C to +125°C
0.5
−40°C to +85°C
−40°C to +125°C
10
100
600
5
50
130
pA
pA
pA
pA
pA
pA
23
9
0.8
0.4
kHz
kHz
kHz
kHz
143
178
1000
1864
μs
μs
μs
μs
11
mV/μs
Vout =1.4V Step
G = 5 + 420 kΩ/RG
5
0.005
0.03
0.06
The AD8235 was designed for low to mid-range gains. Gains can certainly be set beyond 200.
Rev. PrA | Page 4 of 6
2001
V/V
0.05
0.2
0.2
%
%
%
Preliminary Technical Data
Parameter
G =200
Nonlinearity
G=5
G = 10
G = 100
G = 200
Gain vs. Temperature
G=5
G > 10
INPUT
Differential Impedance
Common-Mode Impedance
Input Voltage Range
OUTPUT
Output Voltage High, VOH
Output Voltage Low, VOL
Short-Circuit Limit, ISC
REFERENCE INPUT
RIN
IIN
Voltage Range
Gain to Output
POWER SUPPLY
Operating Range
Quiescent Current
Over Temperature
TEMPERATURE RANGE
For Specified Performance
AD8235
Test Conditions
Min
Typ
0.15
Max
0.3
Unit
%
RL = 10 kΩ or 100 kΩ
RL = 10 kΩ or 100 kΩ
RL = 10 kΩ or 100 kΩ
RL = 10 kΩ or 100 kΩ
1
1
0.5
0.4
10
10
10
10
ppm
ppm
ppm
ppm
−40°C to +125°C
−40°C to +125°C
0.25
1
-50
ppm/°C
ppm/°C
+VS
GΩ||pF
GΩ||pF
V
440||1.6
110||6.2
−40°C to +125°C
0
RL = 100 kΩ to GND
−40°C to +125°C
RL = 10 kΩ to GND
−40°C to +125°C
RL = 100 kΩ to GND
−40°C to +125°C
RL = 10 kΩ to GND
−40°C to +125°C
1.78
1.78
1.65
1.65
1.79
V
V
1.75
2
5
12
25
25
±6
−IN, +IN = 0 V
210
20
−VS
+VS
1
1.8
33
−40
Rev. PrA | Page 5 of 6
V
mV
mV
mV
mV
mA
kΩ
nA
V
V/V
5.5
40
50
V
μA
μA
+125
°C
AD8235
Preliminary Technical Data
OUTLINE DIMENSIONS
(Top View)
3
2
0.19160
A
0.340
0.320
0.300
Ball 1 Identifier
2.080
1
B
C
D
0.30840
1.610
0.380*
0.355
0.330
0.270
0.240
0.210
0.075
Coplanarity
Figure 3. Wafer Level Chip Scale Package (WLCSP)
(CB)
Dimensions shown in millimeters
©2009 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
PR08211-0-4/09(PrA)
Rev. PrA | Page 6 of 6
0.26365 0.50
BALL PITCH
0.26635