INTERSIL EL8188

EL8188
®
Data Sheet
PRELIMINARY
August 25, 2005
Micropower Single Supply Rail-to-Rail
Input-Output Op Amp
The EL8188 is a micropower operational amplifier optimized
for single supply operation at 5V and can operate down to
2.4V.
The EL8188 draws minimal supply current while meeting
excellent DC-accuracy noise and output drive specifications.
Competing devices seriously degrade these parameters to
achieve micropower supply current. Offset current, voltage
and current noise, slew rate, and gain-bandwidth product are
all two to ten times better than on previous micropower op
amps.
The EL8188 can be operated from one lithium cell or two NiCd batteries. The input range includes both positive and
negative rail. The output swings to both rails.
Ordering Information
PART NUMBER
(BRAND)
FN7467.1
Features
• 50µA supply current
• 1mV typical offset voltage
• 0.5 NA input bias current
• 250kHz gain-bandwidth product
• 0.13V/µs slew rate
• Single supply operation down to 2.4V
• Rail-to-rail input and output
• Output sources and sinks 26mA load current
• Pb-Free plus anneal available (RoHS compliant)
Applications
• Battery- or solar-powered systems
• 4mA to 25mA current loops
PACKAGE
TAPE &
REEL
PKG. DWG. #
EL8188IW-T7
(BBKA)
6-Pin SOT-23
7” (3K pcs)
MDP0038
EL8188IW-T7A
(BBKA)
6-Pin SOT-23
7” (250 pcs)
MDP0038
EL8188ISZ
(See Note)
8-Pin SO
(Pb-free)
-
MDP0027
EL8188ISZ-T7
(See Note)
8-Pin SO
(Pb-free)
7”
MDP0027
EL8188ISZ-T13
(See Note)
8-Pin SO
(Pb-free)
13”
MDP0027
NOTE: Intersil Pb-free plus anneal products employ special Pb-free
material sets; molding compounds/die attach materials and 100%
matte tin plate termination finish, which are RoHS compliant and
compatible with both SnPb and Pb-free soldering operations. Intersil
Pb-free products are MSL classified at Pb-free peak reflow
temperatures that meet or exceed the Pb-free requirements of
IPC/JEDEC J STD-020.
• Handheld consumer products
• Medical devices
• Thermocouple amplifiers
• Photodiode pre amps
• pH probe amplifiers
• Pressure sensor pre amp
Pinouts
EL8188
(6-PIN SOT-23)
TOP VIEW
OUT 1
VS- 2
6 VS+
+ -
IN+ 3
5 ENABLE
4 IN-
EL8188
(8-PIN SO)
TOP VIEW
NC 1
IN- 2
IN+ 3
VS- 4
1
8 ENABLE
+
7 VS+
6 VOUT
5 NC
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright © Intersil Americas Inc. 2004, 2005. All Rights Reserved.
All other trademarks mentioned are the property of their respective owners.
EL8188
Absolute Maximum Ratings (TA = 25°C)
Output Short-Circuit Duration . . . . . . . . . . . . . . . . . . . . . . .Indefinite
Ambient Operating Temperature Range . . . . . . . . . .-40°C to +85°C
Storage Temperature Range . . . . . . . . . . . . . . . . . .-65°C to +150°C
Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5V
Differential Input Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5mA
Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to VS + 0.5V
ESD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2kV
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typical values are for information purposes only. Unless otherwise noted, all tests
are at the specified temperature and are pulsed tests, therefore: TJ = TC = TA
Electrical Specifications
PARAMETER
VS = 5V, 0V, VCM = 0.1V, VO = 1.4V, TA = 25°C unless otherwise specified.
DESCRIPTION
CONDITIONS
MIN
TYP
MAX
UNIT
1
4
mV
VOS
Input Offset Voltage
∆V OS
--------------∆T
Input Offset Drift vs Temperature
IB
Input Bias Current
eN
Input Noise Voltage Density
fO = 1kHz
CMIR
Input Voltage Range
Guaranteed by CMRR test
0
CMRR
Common-Mode Rejection Ratio
VCM = 0V to 5V
80
100
dB
PSRR
Power Supply Rejection Ratio
VS = 3.3V to 5V
80
100
dB
AVOL
Large Signal Voltage Gain
VO = 0.5V to 4.5V, RL = 100kΩ
100
400
V/mV
VO = 0.5V to 4.5V, RL = 1kΩ
15
V/mV
Output low, RL = 100kΩ
3
6
mV
130
200
mV
VOUT
Maximum Output Voltage Swing
EL8188IW
1.9
µV/°C
EL8188IS
1.1
µV/°C
0.5
Output high, RL = 1kΩ
NA
35
Output low, RL = 1kΩ
Output high, RL = 100kΩ
1
nV/√Hz
5
V
4.994
4.997
V
4.8
4.88
V
0.09
0.13
SR
Slew Rate
GBW
Gain Bandwidth Product
IS,ON
Supply Current, Enabled
IS,OFF
Supply Current, Disabled
IO+
Short Circuit Output Current
RL = 10Ω
18
31
mA
IO-
Short Circuit Output Current
RL = 10Ω
17
26
mA
VS
Minimum Supply Voltage
VINH
Enable Pin High Level
VINL
Enable Pin Low Level
IENH
Enable Pin Input Current
VEN = 5V
0.25
0.7
2
µA
IENL
Enable Pin Input Current
VEN = 0V
-0.5
0
+0.5
µA
2
fO = 100kHz
0.17
250
40
V/µs
kHz
50
75
µA
3
10
µA
2.2
2.4
V
2
V
0.8
V
FN7467.1
August 25, 2005
EL8188
Typical Performance Curves
1
80
Gain = 1K
Gain = 500
60
0
50
VS = ±1.25
GAIN (dB)
MAGNITUDE (dB)
70
-1
VS = ±2.5V
GAIN = 200
40
GAIN = 100
GAIN = 10
30
GAIN = 5
20
10
-2
GAIN = 2
0
VS = ±1.0V
-3
1K
10K
-10
100K
-20
1M
GAIN =1 V/V
1
10
100
FREQUENCY (Hz)
FIGURE 1. UNITY GAIN FREQUENCY RESPONSE vs
SUPPLY VOLTAGE
200
INPUT OFFSET VOLTAGE (µV)
SUPPLY CURRENT (µA)
50
40
30
20
10
2
2.5
3
4
3.5
4.5
5
0
-100
0.5
50
-50
-150
3.5
4.5
5.5
COMMON-MODE INPUT VOLTAGE (V)
FIGURE 5. INPUT OFFSET VOLTAGE vs COMMON-MODE
INPUT VOLTAGE
3
2.5
3.5
4.5
5.5
FIGURE 4. INPUT OFFSET VOLTAGE vs OUTPUT VOLTAGE
INPUT BIAS, OFFSET CURRENT (fA)
INPUT OFFSET VOLTAGE (µV)
150
2.5
1.5
OUTPUT VOLTAGE (V)
250
1.5
10M
100
-200
-0.5
5.5
FIGURE 3. SUPPLY CURRENT vs SUPPLY VOLTAGE
0.5
100K 1M
AV = -1
VCM = VDD/2
SUPPLY VOLTAGE (V)
-250
-0.5
10K
FIGURE 2. FREQUENCY RESPONSE vs CLOSED LOOP GAIN
60
0
1K
FREQUENCY (Hz)
20
IOS
10
IB0
-10
-20
-0.5
IB+
0.5
1.5
2.5
3.5
4.5
5.5
COMMON-MODE INPUT VOLTAGE (V)
FIGURE 6. INPUT BIAS, OFFSET CURRENT vs COMMONMODE INPUT VOLTAGE
FN7467.1
August 25, 2005
EL8188
Typical Performance Curves (Continued)
80
60
40
PHASE
20
GAIN (dB)
GAIN
0
-20
10
100
1K
10K
100K
1M
-40
10M
110
100
90
80
70
60
50
40
30
20
10
0
-10
-20
-30
-40
100
80
60
PHASE
40
20
GAIN
1
10
100
CMRR (dB)
100
80
60
40
20
1K
10K
100K
1M
120
110
100
90
80
70
60
50
40
30
20
10
0
-10
-20
100K
1M
-40
10M
PSRR+
PSRR-
1
10
100
FREQUENCY (Hz)
1K
10K
100K
1M
FREQUENCY (Hz)
FIGURE 9. CMRR vs FREQUENCY
FIGURE 10. PSRR vs FREQUENCY
800
1000
600
35 6-PIN SOT23 SAMPLES
TYPICAL = 1.9µV/C
400
100
VOS (µV)
VOLTAGE NOISE (nV/√Hz)
10K
FIGURE 8. OPEN LOOP GAIN AND PHASE vs FREQUENCY @
100kΩ
POWER SUPPLY REJECTION RATIO (dB)
120
100
1K
FREQUENCY (Hz)
FIGURE 7. OPEN LOOP GAIN vs FREQUENCY @ 1kΩ
10
0
-20
FREQUENCY (Hz)
0
1
PHASE (°)
100
PHASE (°)
GAIN (dB)
110
100
90
80
70
60
50
40
30
20
10
0
-10
-20
-30
-40
1
10
200
0
-200
-400
-600
1
1
10
100
1K
10K
FREQUENCY (Hz)
FIGURE 11. VOLTAGE NOISE
4
100K
-800
-60
-40
-20
0
20
40
60
80
100 120
TEMPERATURE (°C)
FIGURE 12. SOT VOS vs TEMPERATURE (VS = 5V)
FN7467.1
August 25, 2005
EL8188
Typical Performance Curves (Continued)
300
1
35 SOIC SAMPLES
TYPICAL = 1.1µV/C
0
-100
-200
A
100
909mW
0.8
8
/W
SO 0°C
1
=1
0.6
435mW
0.4
θJ
SO
A =2
T2
3
30
0.2
°C
-6
/W
-300
-400
-60
0
-40
-20
0
20
40
60
80
100 120
0
25
50
75 85 100
125
150
AMBIENT TEMPERATURE (°C)
TEMPERATURE (°C)
FIGURE 14. PACKAGE POWER DISSIPATION vs AMBIENT
TEMPERATURE
FIGURE 13. SOIC VOS vs TEMPERATURE (VS = 5V)
0.7
JEDEC JESD51-3 LOW EFFECTIVE THERMAL
CONDUCTIVITY TEST BOARD
0.6 625mW
A
0.5
8
/W
SO 0°C
6
=1
θJ
POWER DISSIPATION (W)
VOS (µV)
200
JEDEC JESD51-7 HIGH EFFECTIVE THERMAL
CONDUCTIVITY TEST BOARD
θJ
POWER DISSIPATION (W)
400
0.4
391mW
θ
0.3
SO
JA =
0.2
25
T2
3-6
6°
C/
W
0.1
0
0
25
50
75 85 100
125
150
AMBIENT TEMPERATURE (°C)
FIGURE 15. PACKAGE POWER DISSIPATION vs AMBIENT TEMPERATURE
5
FN7467.1
August 25, 2005
EL8188
Applications Information
Typical Applications
Introduction
The EL8188 is a rail-to-rail input and output micro-power
single supply operational amplifier with an enable feature.
The device achieves rail-to-rail input and output operation
and eliminates the concerns introduced by a conventional
rail-to-rail I/O operational amplifier.
V+
+
EL8188
V-
GENERAL
PURPOSE
COMBINATION
pH PROBE
+
COAX
3V
FIGURE 16. PH PROBE AMPLIFIER
Rail-to-Rail Input
The single PFET input stage of the EL8188 has an input
common-mode voltage range that goes from negative supply
to positive supply without introducing offset errors or
degrading performance associated with a conventional railto-rail input operational amplifier. Many rail-to-rail input
stages use dual differential input pairs, a long-tail PNP (or
PFET) and an NPN (or NFET). Severe penalties have to be
paid for this topology. As the input signal moves from one
supply rail to another, the operational amplifier switches from
one input pair to the other causing drastic changes in input
offset voltage and an undesired change in magnitude and
polarity of input offset current.
The EL8188 achieves input rail-to-rail performance without
sacrificing important precision specifications and without
degrading distortion performance. The EL8188's input offset
voltage exhibits a smooth behavior throughout the entire
common-mode input range.
A general-purpose combination pH probe has extremely
high output impedance typically in the range of 10GΩ
to12GΩ. Low loss and expensive Teflon cables are often
used to connect the PH probe to the meter electronics. The
above circuit provides a low-cost alternative solution using
the EL8188 and a low-cost coax cable. The EL8188 PMOS
high impedance input senses the pH probe output signal and
buffers it to drive the coax cable. Its rail-to-rail input nature
also eliminates the need for a bias resistor network required
by other amplifiers in the same application.
R4
100kΩ
R3
10kΩ
R2
K TYPE
THERMOCOUPLE
10kΩ
V+
+
EL8188
V-
410µV/°C
+
5V
Rail-to-Rail Output
A pair of complementary MOSFET devices achieves rail-torail output swing. The NMOS sinks current to swing the
output in the negative direction. The PMOS sources current
to swing the output in the positive direction. The EL8188 with
a 100kΩ load will swing to within 3mV of the supply rails.
Enable/Disable Feature
The EL8188 offers an EN pin. The active low enable pin
disables the device when pulled up to at least 2.2V. Upon
disable the part consumes typically 3µA, while the output is
in a high impedance state. The EN also has an internal pull
down. If left open, the EN pin will pull to negative rail and the
device will be enabled by default. The high impedance at
output during disable allows multiple EL8188’s to be
connected together as a MUX. The outputs are tied together
in parallel and a channel can be selected by the EN pin.
6
R1
100kΩ
FIGURE 17. THERMOCOUPLE AMPLIFIER
Thermocouples are the most popular temperature-sensing
device because of their low cost, interchangeability, and
ability to measure a wide range of temperatures. The
EL8188 is used to convert the differential thermocouple
voltage into single-ended signal with 10X gain. The
EL8188's rail-to-rail input characteristic allows the
thermocouple to be biased at ground and the converter to
run from a single 5V supply.
FN7467.1
August 25, 2005
EL8188
SO Package Outline Drawing
7
FN7467.1
August 25, 2005
EL8188
SOT-23 Package Outline Drawing
NOTE: The package drawing shown here may not be the latest version. To check the latest revision, please refer to the Intersil website at
http://www.intersil.com/design/packages/index.asp
All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.
Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
8
FN7467.1
August 25, 2005