OP
A3
OPA
79
OPA379
OPA2379
OPA4379
OPA
4379
2379
www.ti.com ................................................................................................................................................... SBOS347D – NOVEMBER 2005 – REVISED MAY 2008
1.8V, 2.9µA, 90kHz, Rail-to-Rail I/O
OPERATIONAL AMPLIFIERS
FEATURES
1
•
•
•
•
2
•
•
LOW NOISE: 2.8µVPP (0.1Hz - 10Hz)
microPower: 5.5µA (max)
LOW OFFSET VOLTAGE: 1.5mV (max)
DC PRECISION:
– CMRR: 100dB
– PSRR: 2µV/V
– AOL: 120dB
WIDE SUPPLY VOLTAGE RANGE: 1.8V to 5.5V
microSize PACKAGES:
– SC70-5, SOT23-5, SOT23-8, SO-8, TSSOP-14
APPLICATIONS
•
•
•
•
DESCRIPTION
The OPA379 family of micropower, low-voltage
operational amplifiers is designed for battery-powered
applications. These amplifiers operate on a supply
voltage as low as 1.8V (±0.9V). High-performance,
single-supply operation with rail-to-rail capability
(10µV max) makes the OPA379 family useful for a
wide range of applications.
In addition to microSize packages, the OPA379 family
of op amps features impressive bandwidth (90kHz),
low bias current (5pA), and low noise (80nV/√Hz)
relative to the very low quiescent current (5.5µA
max).
The OPA379 (single) is available in SC70-5,
SOT23-5, and SO-8 packages. The OPA2379 (dual)
comes in SOT23-8 and SO-8 packages. The
OPA4379 (quad) is offered in a TSSOP-14 package.
All versions are specified from –40°C to +125°C.
BATTERY-POWERED INSTRUMENTS
PORTABLE DEVICES
MEDICAL INSTRUMENTS
HANDHELD TEST EQUIPMENT
xxx
xxx
xxx
xxx
xxx
xxx
xxx
VS
Table 1. OPAx379 RELATED PRODUCTS
1/2
OPA2379
FEATURES
C2
C1
C
RF
REF
S
W
VS
RB
RL
R1
1/2
OPA2379
VOUT
PRODUCT
1µA, 70kHz, 2mV VOS, 1.8V to 5.5V Supply
OPAx349
1µA, 5.5kHz, 390µV VOS, 2.5V to 16V Supply
TLV240x
1µA, 5.5kHz, 0.6mV VOS, 2.5V to 12V Supply
TLV224x
7µA, 160kHz, 0.5mV VOS, 2.7V to 16V Supply
TLV27Lx
7µA, 160kHz, 0.5mV VOS, 2.7V to 16V Supply
TLV238x
20µA, 350kHz, 2mV VOS, 2.3V to 5.5V Supply
OPAx347
20µA, 500kHz, 550µV VOS, 1.8V to 3.6V Supply
TLV276x
45µA, 1MHz, 1mV VOS, 2.1V to 5.5V Supply
OPAx348
R1
Figure 1. OPA2379 in Portable Gas Meter
Application
1
2
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2005–2008, Texas Instruments Incorporated
OPA379
OPA2379
OPA4379
SBOS347D – NOVEMBER 2005 – REVISED MAY 2008 ................................................................................................................................................... www.ti.com
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
ABSOLUTE MAXIMUM RATINGS (1)
Over operating free-air temperature range (unless otherwise noted).
Supply Voltage
OPA379, OPA2379, OPA4379
UNIT
+7
V
VS = (V+) – (V–)
Signal Input Terminals, Voltage (2)
(V–) – 0.5 to (V+) + 0.5
V
Signal Input Terminals, Current (2)
±10
mA
Output Short-Circuit (3)
Continuous
Operating Temperature
TA
–40 to +125
°C
Storage Temperature
TA
–65 to +150
°C
Junction Temperature
TJ
+150
°C
Human Body Model
(HBM)
2000
V
Charged Device Model
(CDM)
1000
V
ESD Rating
(1)
(2)
(3)
Stresses above these ratings may cause permanent damage. Exposure to absolute maximum conditions for extended periods may
degrade device reliability. These are stress ratings only, and functional operation of the device at these or any other conditions beyond
those specified is not supported.
Input terminals are diode-clamped to the power-supply rails. Input signals that can swing more than 0.5V beyond the supply rails should
be current-limited to 10mA or less.
Short-circuit to ground, one amplifier per package.
PACKAGE/ORDERING INFORMATION (1)
PRODUCT
PACKAGE-LEAD
PACKAGE DESIGNATOR
PACKAGE MARKING
SC70−5
DCK
AYR
OPA379
SOT23−5
DBV
B53
SO−8
D
OPA379A
SOT23−8
DCN
B61
SO−8
D
OPA2379A
TSSOP−14
PW
OPA4379A
OPA2379
OPA4379
(1)
2
For the most current package and ordering information see the Package Option Addendum at the end of this document, or see the TI
web site at www.ti.com.
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OPA379
OPA2379
OPA4379
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PIN CONFIGURATIONS
OPA379
SC70-5
(TOP VIEW)
+IN
1
V-
2
-IN
3
OPA379
SOT23-5
(TOP VIEW)
5
V+
4
OUT
OUT 1
(1)
V+
4
-IN
V- 2
+IN 3
OPA2379(2)
SOT23-8
(TOP VIEW)
OPA379
SO-8
(TOP VIEW)
8
V+
-IN
2
7
OUT B
OUT
+IN
3
6
-IN B
(1)
V-
4
5
+IN B
NC
-IN 2
7
V+
+IN 3
6
5
NC
OPA2379
SO-8
(TOP VIEW)
B61
1
8
V- 4
(1)
OUT A
1
NC
5
OPA4379
TSSOP-14
(TOP VIEW)
OUT A
1
14
OUT D
OUT B
-IN A
2
13
-IN D
6
-IN B
+IN A
3
12
+IN D
5
+IN B
V+
4
11
V-
+IN B
5
10
+IN C
-IN B
6
9
-IN C
OUT B
7
8
OUT C
OUT A 1
8
V+
-IN A 2
7
+IN A 3
V- 4
(1) NC denotes no internal connection.
(2) Pin 1 of the SOT23−8 package is determined by orienting the
package marking as shown.
Copyright © 2005–2008, Texas Instruments Incorporated
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OPA379
OPA2379
OPA4379
SBOS347D – NOVEMBER 2005 – REVISED MAY 2008 ................................................................................................................................................... www.ti.com
ELECTRICAL CHARACTERISTICS: VS = +1.8V to +5.5V
Boldface limits apply over the specified temperature range indicated.
At TA = +25°C, RL = 25kΩ connected to VS/2, and VCM < (V+) – 1V, unless otherwise noted.
OPA379, OPA2379, OPA4379
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
0.4
1.5
mV
OFFSET VOLTAGE
Initial Offset Voltage
VOS
VS = 5V
Over –40°C to +125°C
Drift, –40°C to +85°C
2
dVOS/dT
Drift, –40°C to +125°C
vs Power Supply
µV/°C
2.7
PSRR
2
Over –40°C to +125°C
mV
µV/°C
1.5
10
µV/V
20
µV/V
INPUT VOLTAGE RANGE
Common-Mode Voltage Range
Common-Mode Rejection Ratio (1)
VCM
CMRR
(V–) – 0.1 to (V+) + 0.1
100
V
(V–) < VCM < (V+) – 1V
90
dB
Over –40°C to +85°C
(V–) < VCM < (V+) – 1V
80
dB
Over –40°C to +125°C
(V–) < VCM < (V+) – 1V
62
dB
INPUT BIAS CURRENT
Input Bias Current
Input Offset Current
IB
VS = 5V, VCM ≤ VS/2
±5
±50
pA
IOS
VS = 5V
±5
±50
pA
INPUT IMPEDANCE
1013 || 3
Differential
13
Common-Mode
10
Ω || pF
Ω || pF
|| 6
NOISE
f = 0.1Hz to 10Hz
2.8
µVPP
Input Voltage Noise Density
en
f = 1kHz
80
nV/√Hz
Input Current Noise Density
in
f = 1kHz
1
fA/√Hz
Input Voltage Noise
OPEN-LOOP GAIN
Open-Loop Voltage Gain
VS = 5V, RL = 25kΩ, 100mV < VO < (V+) – 100mV
100
Over –40°C to +125°C
AOL
VS = 5V, RL = 25kΩ, 100mV < VO < (V+) – 100mV
80
VS = 5V, RL = 5kΩ, 500mV < VO < (V+) – 500mV
100
Over –40°C to +125°C
VS = 5V, RL = 5kΩ, 500mV < VO < (V+) – 500mV
80
120
dB
dB
120
dB
dB
OUTPUT
Voltage Output Swing from Rail
RL = 25kΩ
Over –40°C to +125°C
RL = 25kΩ
Over –40°C to +125°C
RL = 5kΩ
5
RL = 5kΩ
Short-Circuit Current
Capacitive Load Drive
Closed-Loop Output Impedance
ISC
ROUT
RO
FREQUENCY RESPONSE
50
mV
75
mV
mA
G = 1, f = 1kHz, IO = 0
10
Ω
f = 100kHz, IO = 0
28
kΩ
CLOAD = 30pF
SR
Overload Recovery Time
Turn-On Time
4
mV
See Typical Characteristics
GBW
Slew Rate
(1)
mV
15
±5
CLOAD
Open-Loop Output Impedance
Gain Bandwidth Product
25
10
90
kHz
G = +1
0.03
V/µs
VIN × GAIN > VS
25
µs
1
ms
tON
See Typical Characteristic gragh, Common-Mode Rejection Ratio vs Frequency (Figure 3).
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OPA2379
OPA4379
www.ti.com ................................................................................................................................................... SBOS347D – NOVEMBER 2005 – REVISED MAY 2008
ELECTRICAL CHARACTERISTICS: VS = +1.8V to +5.5V (continued)
Boldface limits apply over the specified temperature range indicated.
At TA = +25°C, RL = 25kΩ connected to VS/2, and VCM < (V+) – 1V, unless otherwise noted.
OPA379, OPA2379, OPA4379
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
POWER SUPPLY
Specified/Operating Voltage Range
VS
Quiescent Current per Amplifier
IQ
1.8
VS = 5.5V, IO = 0
2.9
Over –40°C to +125°C
5.5
V
5.5
µA
10
µA
TEMPERATURE
Specified/Operating Range
TA
–40
+125
°C
Storage Range
TJ
–65
+150
°C
Thermal Resistance
θJA
SC70−5
250
°C/W
SOT23−5
200
°C/W
SOT23−8, TSSOP−14, SO−8
150
°C/W
Copyright © 2005–2008, Texas Instruments Incorporated
Product Folder Link(s): OPA379 OPA2379 OPA4379
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OPA379
OPA2379
OPA4379
SBOS347D – NOVEMBER 2005 – REVISED MAY 2008 ................................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS
At TA = +25°C, VS = 5V, and RL = 25kΩ connected to VS/2, unless otherwise noted.
COMMON-MODE AND
POWER-SUPPLY REJECTION RATIO
vs FREQUENCY
0
120
100
-30
100
80
-60
60
-90
40
-120
20
-150
20
-180
100k
0
0
0.1
1
10
100
1k
10k
CMRR and PSRR (dB)
120
Phase (°)
Gain (dB)
OPEN-LOOP GAIN AND PHASE
vs FREQUENCY
-PSRR
80
+PSRR
60
40
CMRR
0.1
1
10
Frequency (Hz)
100
1k
Frequency (Hz)
10k
Figure 2.
Figure 3.
MAXIMUM OUTPUT VOLTAGE
vs FREQUENCY
QUIESCENT CURRENT
vs SUPPLY VOLTAGE
100k
3.5
5.0
4.5
Quiescent Current (mA)
Output Voltage (VPP)
4.0
3.5
3.0
2.5
2.0
1.5
1.0
3.0
2.5
2.0
0.5
1.5
0
1k
10k
100k
1.5
2.0
2.5
Frequency (Hz)
3.5
4.0
4.5
Figure 4.
Figure 5.
OUTPUT VOLTAGE
vs OUTPUT CURRENT
SHORT-CIRCUIT CURRENT
vs SUPPLY VOLTAGE
2.5
5.0
5.5
5.0
5.5
25
2.0
VS = ±2.5V
1.0
0.5
+125°C
0
+85°C
+25°C
-40°C
-0.5
-1.0
-1.5
Short-Circuit Current (mA)
+ISC
1.5
VOUT (V)
3.0
Supply Voltage (V)
20
-ISC
15
10
-2.0
5
-2.5
0
1
2
3
4
5
6
7
8
9
10
1.5
2.0
2.5
IOUT (mA)
Figure 6.
6
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3.0
3.5
4.0
4.5
Supply Voltage (V)
Figure 7.
Copyright © 2005–2008, Texas Instruments Incorporated
Product Folder Link(s): OPA379 OPA2379 OPA4379
OPA379
OPA2379
OPA4379
www.ti.com ................................................................................................................................................... SBOS347D – NOVEMBER 2005 – REVISED MAY 2008
TYPICAL CHARACTERISTICS (continued)
At TA = +25°C, VS = 5V, and RL = 25kΩ connected to VS/2, unless otherwise noted.
OFFSET VOLTAGE vs COMMON-MODE VOLTAGE
vs TEMPERATURE
15.0
12.5
Unit 1
Common-Mode Input Range
10.0
7.5
CMRR Specified Range
5.0
Population
2.5
0
-2.5
-5.0
-7.5
-40°C
+85°C
+125°C
-10.0
-12.5
-15.0
-0.5 0
Unit 2
-1500
-1350
-1200
-1050
-900
-750
-600
-450
-300
-150
0
150
300
450
600
750
900
1050
1200
1350
1500
Offset Voltage (mV)
OFFSET VOLTAGE
PRODUCTION DISTRIBUTION
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
Common-Mode Voltage (V)
Offset Voltage (mV)
Figure 9.
OFFSET VOLTAGE DRIFT DISTRIBUTION
(–40°C to +85°C)
OFFSET VOLTAGE DRIFT DISTRIBUTION
(–40°C to +125°C)
Population
Population
Figure 8.
£1
£2
£3
£4
£5
£1
>5
£2
£3
£4
£5
>5
Offset Voltage Drift (mV/°C)
Offset Voltage Drift (mV/°C)
Figure 10.
Figure 11.
QUIESCENT CURRENT
vs TEMPERATURE
QUIESCENT CURRENT
PRODUCTION DISTRIBUTION
5.0
4.5
Population
4.0
IQ (mA)
3.5
3.0
2.5
2.0
1.0
-50
-25
0
25
50
75
100
125
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
4.8
5.0
1.5
Temperature (°C)
Figure 12.
Quiescent Current (mA)
Figure 13.
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OPA379
OPA2379
OPA4379
SBOS347D – NOVEMBER 2005 – REVISED MAY 2008 ................................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS (continued)
At TA = +25°C, VS = 5V, and RL = 25kΩ connected to VS/2, unless otherwise noted.
INPUT BIAS CURRENT
vs TEMPERATURE
0.1Hz TO 10Hz NOISE
10000
100
1mV/div
Input Bias Current (pA)
1000
10
1
0.1
0.01
-50
0
-25
25
50
Temperature (°C)
75
100
2.5s/div
125
Figure 14.
Figure 15.
NOISE vs FREQUENCY
SMALL-SIGNAL OVERSHOOT
vs CAPACITIVE LOAD
1000
60
Overshoot (%)
Noise (nV/ÖHz)
50
100
40
30
G = +1
20
10
G = -1
10
0
1
10
100
1k
10k
10
100
Frequency (Hz)
Figure 17.
SMALL-SIGNAL STEP RESPONSE
LARGE-SIGNAL STEP RESPONSE
500mV/div
Figure 16.
20mV/div
8
1000
Capacitive Load (pF)
25ms/div
50ms/div
Figure 18.
Figure 19.
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OPA379
OPA2379
OPA4379
www.ti.com ................................................................................................................................................... SBOS347D – NOVEMBER 2005 – REVISED MAY 2008
APPLICATION INFORMATION
The OPA379 family of operational amplifiers
minimizes power consumption without compromising
bandwidth or noise. Power-supply rejection ratio
(PSRR), common-mode rejection ratio (CMRR), and
open-loop gain (AOL) typical values are 100dB or
better.
When designing for ultra-low power, choose system
components
carefully.
To
minimize
current
consumption, select large-value resistors. Any
resistors will react with stray capacitance in the circuit
and the input capacitance of the operational amplifier.
These parasitic RC combinations can affect the
stability of the overall system. A feedback capacitor
may be required to assure stability and limit
overshoot or gain peaking.
Good layout practice mandates the use of a 0.1µF
bypass capacitor placed closely across the supply
pins.
OPERATING VOLTAGE
OPA379 series op amps are fully specified and tested
from +1.8V to +5.5V (±0.9V to ±2.75V). Parameters
that will vary with supply voltage are shown in the
Typical Characteristics curves.
INPUT COMMON-MODE VOLTAGE RANGE
The input common-mode voltage range of the
OPA379 family typically extends 100mV beyond each
supply rail. This rail-to-rail input is achieved using a
complementary input stage. CMRR is specified from
the negative rail to 1V below the positive rail.
Between (V+) – 1V and (V+) + 0.1V, the amplifier
operates with higher offset voltage because of the
transition region of the input stage. See the typical
characteristic, Offset Voltage vs Common-Mode
Voltage vs Temperature (Figure 8).
PROTECTING INPUTS FROM
OVER-VOLTAGE
Normally, input currents are 5pA. However, a large
voltage input (greater than 500mV beyond the supply
rails) can cause excessive current to flow in or out of
the input pins. Therefore, as well as keeping the input
voltage below the maximum rating, it is also important
to limit the input current to less than 10mA. This
limiting is easily accomplished with an input voltage
resistor, as shown in Figure 20.
VS
IOVERLOAD
10mA max
OPA379
VOUT
VIN
5kW
Figure 20. Input Current Protection for Voltages
Exceeding the Supply Voltage
NOISE
Although micropower amplifiers frequently have high
wideband noise, the OPA379 series offer excellent
noise performance. Resistors should be chosen
carefully because the OPA379 has only 2.8µVPP of
0.1Hz to 10Hz noise, and 80nV/√Hz of wideband
noise; otherwise, they can become the dominant
source of noise.
CAPACITIVE LOAD AND STABILITY
Follower configurations with load capacitance in
excess of 30pF can produce extra overshoot (see
typical characteristic Small-Signal Overshoot vs
Capacitive Load, Figure 17) and ringing in the output
signal. Increasing the gain enhances the ability of the
amplifier to drive greater capacitive loads. In
unity-gain configurations, capacitive load drive can be
improved by inserting a small (10Ω to 20Ω) resistor,
RS, in series with the output, as shown in Figure 21.
This resistor significantly reduces ringing while
maintaining direct current (dc) performance for purely
capacitive loads. However, if there is a resistive load
in parallel with the capacitive load, a voltage divider is
created, introducing a dc error at the output and
slightly reducing the output swing. The error
introduced is proportional to the ratio RS/RL, and is
generally negligible.
VS
RS
VOUT
OPA379
VIN
10W to
20W
RL
CL
Figure 21. Series Resistor in Unity-Gain Buffer
Configuration Improves Capacitive Load Drive
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OPA379
OPA2379
OPA4379
SBOS347D – NOVEMBER 2005 – REVISED MAY 2008 ................................................................................................................................................... www.ti.com
In unity-gain inverter configuration, phase margin can
be reduced by the reaction between the capacitance
at the op amp input and the gain setting resistors.
Best performance is achieved by using smaller
valued resistors. However, when large valued
resistors cannot be avoided, a small (4pF to 6pF)
capacitor, CFB, can be inserted in the feedback, as
shown in Figure 22. This configuration significantly
reduces overshoot by compensating the effect of
capacitance, CIN, which includes the amplifier input
capacitance (3pf) and printed circuit board (PC)
parasitic capacitance.
CFB
RF
RIN
VIN
OPA379
VOUT
CIN
RF =
=
VREF
1000(IBMAX)
1.2V
1000(100pA)
= 12MW » 10MW
(1)
2. Choose the hysteresis voltage, VHYST. For battery
monitoring applications, 50mV is adequate.
3. Calculate R1 as follows:
VHYST
50mW
R 1 = RF
= 10MW
= 210kW
VBATT
2.4V
(2)
4. Select a threshold voltage for VIN rising (VTHRS) =
2.0V
5. Calculate R2 as follows:
1
R2 =
VTHRS
1
1
R1
RF
VREF ´ R1
1
=
1
2V
1
10MW
1.2V ´ 210kW
210kW
Figure 22. Improving Stability for Large RF and RIN
BATTERY MONITORING
= 325kW
The low operating voltage and quiescent current of
the OPA379 series make it an excellent choice for
battery monitoring applications, as shown in
Figure 23. In this circuit, VSTATUS is high as long as
the battery voltage remains above 2V. A low-power
reference is used to set the trip point. Resistor values
are selected as follows:
1. RF Selecting: Select RF such that the current
through RF is approximately 1000x larger than
the maximum bias current over temperature:
(3)
6. Calculate RBIAS: The minimum supply voltage for
this circuit is 1.8V. The REF1112 has a current
requirement of 1.2µA (max). Providing 2µA of
supply current assures proper operation.
Therefore:
(VBATTMIN - VREF)
(1.8V - 1.2V)
=
= 0.3MW
RBIAS =
IBIAS
2 mA
(4)
RF
R1
+IN
+
IBIAS
VBATT
OPA379
RBIAS
OUT
VSTATUS
-IN
VREF
R2
REF1112
Figure 23. Battery Monitor
10
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OPA4379
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WINDOW COMPARATOR
The window comparator threshold voltages are set as
follows:
R2
´ VS
VH =
R 1 + R2
(5)
R4
´ VS
VL =
R 3 + R4
(6)
Figure 24 shows the OPA2379 used as a window
comparator. The threshold limits are set by VH and
VL, with VH > VL. When VIN < VH, the output of A1 is
low. When VIN > VL, the output of A2 is low.
Therefore, both op amp outputs are at 0V as long as
VIN is between VH and VL. This architecture results in
no current flowing through either diode, Q1 in cutoff,
with the base voltage at 0V, and VOUT forced high.
If VIN falls below VL, the output of A2 is high, current
flows through D2, and VOUT is low. Likewise, if VIN
rises above VH, the output of A1 is high, current flows
through D1, and VOUT is low.
VS
VS
R1
VH
A1
1/2
OPA2379
R2
D1
(2)
VS
R7
5.1kW
RIN
VOUT
R5
10kW
(1)
2kW
VIN
(3)
Q1
R6
5.1kW
VS
VS
A2
R3
VL
1/2
OPA2379
D2
(2)
R4
(1) RIN protects A1 and A2 from possible excess current flow.
(2) IN4446 or equivalent diodes.
(3) 2N2222 or equivalent NPN transistor.
Figure 24. OPA2379 as a Window Comparator
Copyright © 2005–2008, Texas Instruments Incorporated
Product Folder Link(s): OPA379 OPA2379 OPA4379
Submit Documentation Feedback
11
OPA379
OPA2379
OPA4379
SBOS347D – NOVEMBER 2005 – REVISED MAY 2008 ................................................................................................................................................... www.ti.com
ADDITIONAL APPLICATION EXAMPLES
Figure 25 through Figure 29 illustrate additional application examples.
+2.7V
R3
R2
VCC
+2.7V
MSP430x20x3PW
R1
66.5W
A0+
16-Bit
ADC
OPA379
C1
1.5nF
VIN
VREF
REF3312
VSS
C2
1m F
Figure 25. Unipolar Signal Chain Configuration
VEX
R1
VS
R R
R R
VOUT
OPA379
R1
VREF
Figure 26. Single Op Amp Bridge Amplifier
+5V
REF3130
3V
Load
R1
4.99kW
R2
49.9kW
R6
71.5kW
V
ILOAD
RSHUNT
1W
RN
56W
OPA379
R3
4.99kW
Stray Ground-Loop Resistance
R4
48.7kW
ADS1100
R7
1.18kW
RN
56W
2
IC
(PGA Gain = 4)
FS = 3.0V
NOTE: 1% resistors provide adequate common-mode rejection at small ground-loop errors.
Figure 27. Low-Side Current Monitor
12
Submit Documentation Feedback
Copyright © 2005–2008, Texas Instruments Incorporated
Product Folder Link(s): OPA379 OPA2379 OPA4379
OPA379
OPA2379
OPA4379
www.ti.com ................................................................................................................................................... SBOS347D – NOVEMBER 2005 – REVISED MAY 2008
RG
zener
RSHUNT
(1)
V+
(2)
R1
10kW
MOSFET rated to
stand-off supply voltage
such as BSS84 for
up to 50V.
OPA379
V+5V
Two zener
biasing methods
(3)
are shown.
Output
Load
RBIAS
RL
(1) Zener rated for op amp supply capability (that is, 5.1V for OPA379).
(2) Current-limiting resistor.
(3) Choose zener biasing resistor or dual NMOSMETs (FDG6301N, NTJD4001N, or Si1034).
Figure 28. High-Side Current Monitor
RG
VREF
R1
R2
R2
1/2
OPA2379
V2
R1
VOUT
1/2
OPA2379
V1
VOUT = (V1 - V2) 1 +
R1 2R1
+
+ VREF
R2
RG
Figure 29. Two Op Amp Instrumentation Amplifier
Copyright © 2005–2008, Texas Instruments Incorporated
Product Folder Link(s): OPA379 OPA2379 OPA4379
Submit Documentation Feedback
13
PACKAGE OPTION ADDENDUM
www.ti.com
14-Oct-2022
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
Samples
(4/5)
(6)
OPA2379AID
ACTIVE
SOIC
D
8
75
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
2379A
Samples
OPA2379AIDCNR
ACTIVE
SOT-23
DCN
8
3000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
BPK
Samples
OPA2379AIDCNT
ACTIVE
SOT-23
DCN
8
250
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
BPK
Samples
OPA2379AIDG4
ACTIVE
SOIC
D
8
75
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
2379A
Samples
OPA2379AIDR
ACTIVE
SOIC
D
8
2500
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
2379A
Samples
OPA379AID
ACTIVE
SOIC
D
8
75
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
OPA
379A
Samples
OPA379AIDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
B53
Samples
OPA379AIDBVRG4
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
B53
Samples
OPA379AIDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
B53
Samples
OPA379AIDCKR
ACTIVE
SC70
DCK
5
3000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
B54
Samples
OPA379AIDCKT
ACTIVE
SC70
DCK
5
250
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
B54
Samples
OPA379AIDCKTG4
ACTIVE
SC70
DCK
5
250
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
B54
Samples
OPA379AIDR
ACTIVE
SOIC
D
8
2500
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
OPA
379A
Samples
OPA379AIDRG4
ACTIVE
SOIC
D
8
2500
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
OPA
379A
Samples
OPA4379AIPWR
ACTIVE
TSSOP
PW
14
2000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
4379A
Samples
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
14-Oct-2022
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of