AD 5962-8967001CA

a
FEATURES
Single/Dual-Supply Operation
1.6 V to 36 V
ⴞ0.8 V to ⴞ18 V
True Single-Supply Operation; Input and Output
Voltage Ranges Include Ground
Low Supply Current: 80 ␮A Max
High Output Drive: 5 mA Min
Low Offset Voltage: 0.5 mA Max
High Open-Loop Gain: 700 V/mV Min
Outstanding PSRR: 5.6 mV/V Min
Industry Standard Quad Pinouts
Available in Die Form
Low Voltage Micropower
Quad Operational Amplifier
OP490
PIN CONNECTION
14-Lead Hermetic DIP
(Y Suffix)
OUT A
1
14 OUT D
–IN A
2
13 –IN D
+IN A
3
12 +IN D
V+
4
11 V–
+IN B 5
10 +IN C
6
9 –IN C
–IN B
OUT B 7
8 OUT C
14-Lead Plastic DIP
(P Suffix)
GENERAL DESCRIPTION
The OP490 is a high-performance micropower quad op amp
that operates from a single supply of 1.6 V to 36 V or from
dual supplies of ± 0.8 V to ± 18 V. Input voltage range includes
the negative rail allowing the OP490 to accommodate input
signals down to ground in single-supply operation. The
OP490’s output swing also includes ground when operating
from a single supply, enabling “zero-in, zero-out” operation.
The quad OP490 draws less than 20 mA of quiescent supply
current per amplifier, but each amplifier is able to deliver
over 5 mA of output current to a load. Input offset voltage is
under 0.5 mV with offset drift below 5 mV/∞C over the military
temperature range. Gain exceeds over 700,000 and CMR is
better than 100 dB. A PSRR of under 5.6 mV/V minimizes
offset voltage changes experienced in battery-powered systems.
The quad OP490 combines high performance with the space
and cost savings of quad amplifiers. The minimal voltage and
current requirements of the OP490 make it ideal for batteryand solar-powered applications, such as portable instruments
and remote sensors.
OUT A
1
14 OUT D
–IN A
2
13 –IN D
+IN A
3
12 +IN D
V+
4
11 V–
+IN B
5
10 +IN C
–IN B
6
9 –IN C
OUT B 7
8 OUT C
16-Lead SOIC
(S Suffix)
OUT A
1
16 OUT D
–IN A
2
15 –IN D
+IN A
3
14 +IN D
V+
4
13 V–
+IN B
5
12 +IN C
–IN B
6
11 –IN C
OUT B
7
10 OUT C
NC
8
9 NC
NC = NO CONNECT
REV. C
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. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 2002
OP490–SPECIFICATIONS
ELECTRICAL CHARACTERISTICS (@ V = ⴞ1.5 V to ⴞ15 V, T = 25ⴗC, unless otherwise noted)
S
Parameter
Symbol
Input Offset
Voltage
VOS
Input Offset
Current
IOS
Input Bias
Current
Large Signal
Voltage Gain
Conditions
A
Min
OP490E
Typ
Max
Min
OP490F
Typ
Max
Min
OP490G
Typ
Max
Unit
0.2
0.5
0.4
0.75
0.6
1.0
mV
VCM = 0 V
0.4
3.0
0.4
5
0.4
5
nA
IB
VCM = 0 V
4.2
15.0
4.2
20
4.2
25
nA
AVO
VS = ± 15 V, VO = ± 10 V,
RL = 100 kW
RL = 10 kW
RL = 2 kW
V+ = 5 V, V– = 0 V,
1 V < VO < 4 V
RL = 100 kW
RL = 10 kW
700
350
125
1,200
600
250
500
250
100
1,000
500
200
400
200
100
800
400
200
V/mV
V/mV
V/mV
200
100
400
180
125
75
300
140
100
70
250
140
V/mV
V/mV
Input Voltage
Range
IVR
V+ = 5 V, V– = 0 V
VS = ± 15 V1
0/4
–15/+13.5
0/4
–15/+13.5
0/4
–15/+13.5
V
V
Output Voltage
Swing
VO
VS = ± 15 V, RL = 10 kW
RL = 2 kW
V+ = 5 V, V– = 0 V,
RL = 2 kW
V+ = 5 V, V– = 0 V,
RL = 10 kW
± 13.5
± 10.5
± 14.2
± 11.5
± 13.5
± 10.5
± 14.2
± 11.5
± 13.5
± 10.5
± 14.2
± 11.5
V
V
4.0
4.2
4.0
4.2
4.0
4.2
V
V+ = 5 V, V– = 0 V,
0 V < VCM < 4 V
VS = ± 15 V,
–15 V < VCM < +13.5 V
90
110
80
100
800
100
dB
100
130
90
120
90
120
dB
VOH
VOL
Common-Mode
Rejection Ratio
CMRR
100
500
100
500
100
500
mV
Power Supply
Rejection Ratio
PSRR
Slew Rate
SR
VS = ± 15 V
Supply Current
(All Amplifiers)
ISY
VS = ± 1.5 V, No Load
VS = ± 15 V, No Load
40
60
AV = 1
650
650
650
pF
fO = 0.1 Hz to 10 Hz,
VS = ± 15 V
3
3
3
mV p-p
Capacitive Load
Stability
Input Noise
Voltage
en p-p
1.0
5
5.6
12
3.2
5
60
80
10
12
40
60
3.2
5
60
80
10
12
40
60
mV/V
V/ms
60
80
mA
mA
Input Resistance
Differential Mode
RIN
VS = ± 15 V
30
30
30
MW
Input Resistance
Common-Mode
RINCM
VS = ± 15 V
20
20
20
GW
Gain Bandwidth
Product
GBWP
AV = 1
Channel Separation
CS
fO = 10 Hz, VO = 20 V p-p
VS = ± 15 V2
20
120
150
20
120
150
120
20
kHz
150
dB
NOTES
1
Guaranteed by CMRR test.
2
Guaranteed but not 100% tested.
Specifications subject to change without notice
–2–
REV. C
OP490
(@ VS = ⴞ1.5 V to ⴞ15 V, –25ⴗC £ TA £ +85ⴗC for OP490E/F, –40ⴗC £ TA £ +125ⴗC for
ELECTRICAL CHARACTERISTICS OP490G, unless otherwise noted)
Parameter
Symbol
Input Offset
Voltage
VOS
Average Input
Offset Voltage Drift
TCVOS
Input Offset
Current
Input Bias
Current
Large Signal
Voltage Gain
Conditions
Min
OP490E
Typ
Max
Min
OP490F
Typ
Max
Min
1.35
OP490G
Typ
Max
0.8
1.5
Unit
0.32
0.8
0.6
mV
VS = ± 15 V
2
5
4
IOS
VCM = 0 V
0.8
3
1.0
5
1.3
7
nA
IB
VCM = 0 V
4.4
15
4.4
20
4.4
25
nA
AVO
VS = ± 15 V, VO = ± 10 V,
RL = 100 kW
RL = 10 kW
RL = 2 kW
V+ = 5 V, V– = 0 V,
1 V < VO < 4 V
RL = 100 kW
RL = 10 kW
mV/∞C
4
500
250
100
800
400
200
350
175
75
700
250
150
300
150
75
600
250
125
V/mV
V/mV
V/mV
150
75
280
140
100
50
220
110
80
40
160
90
V/mV
V/mV
Input Voltage
Range
IVR
V+ = 5 V, V– = 0 V
VS = ± 15 V*
0.3/5
–15/+13.5
0.3/5
–15/+13.5
0.3/5
–15/+13.5
V
V
Output Voltage
Swing
VO
VS = ± 15 V, RL = 10 kW
RL = 2 kW
V+ = 5 V, V– = 0 V,
RL = 2 kW
V+ = 5 V, V– = 0 V,
RL = 10 kW
± 13
± 10
± 14
± 11
± 13
± 10
± 14
± 11
± 13
± 10
± 14
± 11
V
V
3.9
4.1
3.9
4.1
3.9
4.1
V
V+ = 5 V, V– = 0 V,
0 V < VCM < 3.5 V
VS = ± 15 V,
–15 V < VCM < +13.5 V
90
110
80
100
800
100
dB
100
120
90
110
90
110
dB
VOH
VOL
Common-Mode
Rejection Ratio
CMRR
Power Supply
Rejection Ratio
PSRR
Supply Current
(All Amplifiers)
ISY
VS = ± 1.5 V, No Load
VS = ± 15 V, No Load
100
100
500
100
500
mV
1.0
5.6
3.2
10
5.6
17.8
mV/V
65
80
100
120
65
80
100
120
60
75
100
120
mA
mA
NOTE
*Guaranteed by CMRR test.
Specifications subject to change without notice
REV. C
500
–3–
OP490
WAFER TEST LIMITS (@ V = ⴞ1.5 V to ⴞ15 V, T = 25ⴗC, unless otherwise noted)
S
Parameter
A
Symbol
Input Offset Voltage
Input Offset Current
Input Bias Current
Large Signal Voltage Gain
VOS
IOS
IB
AVO
Input Voltage Range
IVR
Output Voltage Swing
VO
VOH
VOL
Common-Mode Rejection Ratio
CMRR
Power Supply Rejection Ratio
PSRR
Supply Current (All Amplifiers)
ISY
Conditions
Limits
Unit
0.75
5
20
mV max
nA max
nA max
500
250
125
V/mV min
V/mV min
V/mV min
VCM = 0 V
VCM = 0 V
VS = ± 15 V, VO = ± 10 V,
RL = 100 kW
RL = 10 kW
V+ = 5 V, V– = 0 V
1 V < VO < 4 V, RL = 100 kW
V+ = 5 V, V– = 0 V
VS = ± 15 V*
VS = ± 15 V
RL = 10 kW
RL = 2 kW
V+ = 5 V, V– = 0 V, RL = 2 kW
V+ = 5 V, V– = 0 V, RL = 10 kW
0/4
–15/+13.5
V min
V min
± 13.5
± 10.5
4.0
500
V min
V min
V min
mV max
V+ = 5 V, V– = 0 V, 0 V < VCM < 4 V
VS = ± 15 V, –15 V < VCM < +13.5 V
80
90
dB min
dB min
10
mV/V max
80
mA max
VS = ± 15 V, No Load
NOTE
*Guaranteed by CMRR test.
Electrical tests are performed at wafer probe to the limits shown. Due to variations in assembly methods and normal yield loss, yield after packaging is not guaranteed
for standard product dice. Consult factory to negotiate specifications based on dice lot qualifications through sample lot assembly and testing.
V+
+IN
OUTPUT
–IN
V–
Figure 1. Simplified Schematic
–4–
REV. C
OP490
ABSOLUTE MAXIMUM RATINGS*
Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 18 V
Digital Input Voltage . . . . . . . . [(V–) – 20 V] to [(V+) + 20 V]
Common-Mode Input Voltage [(V–) – 20 V] to [(V+) + 20 V]
Output Short Circuit Duration . . . . . . . . . . . . . . . Continuous
Storage Temperature Range
Y and P Packages . . . . . . . . . . . . . . . . . . . –65∞C to +150∞C
Operating Temperature Range
OP490E, OP490F . . . . . . . . . . . . . . . . . . . –25∞C to +85∞C
OP490G . . . . . . . . . . . . . . . . . . . . . . . . . . . –40∞C to +85∞C
Junction Temperature (TJ) . . . . . . . . . . . . . –65∞C to +150∞C
Lead Temperature Range (Soldering, 60 sec) . . . . . . . . 300∞C
*Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the
device at these or any other conditions above those listed in the operational
sections of this specification is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability.
Package Type
␪JA*
␪JC
Unit
14-Pin Hermetic DIP (Y)
14-Pin Plastic DIP (P)
16-Pin SOL (S)
99
76
92
12
33
27
∞C/W
∞C/W
∞C/W
*qJA is specified for worst case mounting conditions, i.e., qJA is specified for
device in socket for CERDIP and PDIP packages; qJA is specified for device
soldered to printed circuit board for SOL package
ORDERING GUIDE
Model
Temperature
Range
Package
Description
Package
Option
OP490EY*
OP490FY*
OP490GP
OP490GS
–25∞C to +85∞C
–25∞C to +85∞C
–40∞C to +85∞C
–40∞C to +85∞C
14-Lead CERDIP
14-Lead CERDIP
14-Lead Plastic DIP
16-Lead SOIC
Y-14
Y-14
P-14
S-14
*Not recommended for new designs. Obsolete April 2002.
For Military processed devices, please refer to the Standard
Microcircuit Drawing (SMD) available at
www.dscc.dla.mil/programs/milspec/default.asp
SMD Part Number
ADI Equivalent
5962-89670013A*
5962-8967001CA*
OP490ATCMDA
OP490AYMDA
*Not recommended for new designs. Obsolete April 2002.
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection. Although
the OP490 features proprietary ESD protection circuitry, permanent damage may occur on devices
subjected to high-energy electrostatic discharges. Therefore, proper ESD precautions are
recommended to avoid performance degradation or loss of functionality.
REV. C
–5–
WARNING!
ESD SENSITIVE DEVICE
OP490 –Typical Performance Characteristics
90
0.4
TOTAL SUPPLY CURRENT – ␮A
INPUT OFFSET VOLTAGE – mV
VS = 15V
0.3
0.2
0.1
80
70
60
VS = 15V
50
40
VS = 1.5V
0
–75
–50
–25
0
25
TEMPERATURE – ⴗC
50
75
30
–75
125
TPC 1. Input Offset Voltage vs. Temperature
0
25
TEMPERATURE – ⴗC
50
125
75
600
TA = 25ⴗC
RL = 10k⍀
VS = 15V
1.4
500
25ⴗC
OPEN-LOOP GAIN – V/mV
1.2
1.0
0.8
0.6
400
85ⴗC
300
125ⴗC
200
100
0.4
0.2
–75
–50
–25
0
25
TEMPERATURE – ⴗC
50
75
0
125
5
10
15
20
SINGLE-SUPPLY VOLTAGE – V
25
30
TPC 5. Open-Loop Gain vs. Single-Supply Voltage
TPC 2. Input Offset Current vs. Temperature
140
4.8
VS = 15V
120
OPEN-LOOP GAIN – dB
4.6
4.4
4.2
4.0
3.8
3.6
–75
0
–50
–25
0
25
TEMPERATURE – ⴗC
50
75
0
100
GAIN
80
45
60
90
40
135
20
180
0
0.1
125
VS = 15V
TA = 25ⴗC
RL = 10k⍀
1
10
100
1k
FREQUENCY – Hz
10k
PHASE SHIFT – Degrees
INPUT OFFSET CURRENT – nA
–25
TPC 4. Total Supply Current vs. Temperature
1.6
INPUT BIAS CURRENT – nA
–50
100k
TPC 6. Open-Loop Gain and Phase Shift vs. Frequency
TPC 3. Input Bias Current vs. Temperature
–6–
REV. C
OP490
60
120
VS = 15V
TA = 25ⴗC
POWER SUPPLY REJECTION – dB
TA = 25ⴗC
CLOSED-LOOP GAIN – dB
40
20
0
–20
10
100
1k
FREQUENCY – Hz
10k
100
80
POSITIVE SUPPLY
60
40
20
100k
TPC 7. Closed-Loop Gain vs. Frequency
NEGATIVE SUPPLY
100
10
LOAD RESISTANCE – ⍀
1
1k
TPC 10. Power Supply Rejection vs. Frequency
140
6
V+ = 5V, V– = 0V
TA = 25ⴗC
VS = 15V
TA = 25ⴗC
COMMON-MODE REJECTION – dB
OUTPUT VOLTAGE SWING – V
5
4
3
2
1
0
100
10k
1k
LOAD RESISTANCE – ⍀
80
60
1
10
FREQUENCY – Hz
1k
100
TPC 11. Common-Mode Rejection vs. Frequency
1k
16
VS = 15V
TA = 25ⴗC
POSITIVE
VOLTAGE NOISE DENSITY – nV/ Hz
VS = 15
TA = 25ⴗC
NEGATIVE
12
OUTPUT SWING – V
100
40
0.1
100k
TPC 8. Output Voltage Swing vs. Load Resistance
14
120
10
8
6
4
100
10
2
0
100
1
10k
1k
LOAD RESISTANCE – ⍀
0.1
100k
10
FREQUENCY – Hz
100
1k
TPC 12. Noise Voltage Density vs. Frequency
TPC 9. Output Voltage Swing vs. Load Resistance
REV. C
1
–7–
OP490
0
100
VS = 15V
TA = 25ⴗC
AV = 1
RL = 10k⍀
CL = 500pF
0
0
VOLTAGE – 5V/DIV
VOLTAGE NOISE DENSITY – nV/ Hz
VS = 15V
TA = 25ⴗC
10
1
0
0
0
0
0
0.1
1
0.1
10
FREQUENCY – Hz
100
0
1k
0
TPC 13. Current Noise Density vs. Frequency
0
0
0
0
0
0
TIME – 1ms/DIV
0
0
0
0
TPC 15. Large-Signal Transient Response
0
VS = 15V
TA = 25ⴗC
AV = 1
RL = 10k⍀
CL = 500pF
0
VOLTAGE – 20mV/DIV
0
0
0
0
0
0
0
0
0
0
0
0
0
0
TIME – 100␮s/DIV
0
0
0
0
TPC 14. Small-Signal Transient Response
–8–
REV. C
OP490
–18V
APPLICATIONS INFORMATION
Battery-Powered Applications
1
13
12
11
9
10
D
C
A
B
2
3
4
High performance portable equipment and instruments frequently use lithium cells because of their long shelf-life, light
weight, and high energy density relative to older primary cells.
Most lithium cells have a nominal output voltage of 3 V and are
noted for a flat discharge characteristic. The low supply current
6
5
8
7
4
LITHIUM-SULPHUR DIOXIDE CELL VOLTAGE – V
14
The OP490 can be operated on a minimum supply voltage of
1.6 V, or with dual supplies of ± 0.8 V, and draws only 60 mA of
supply current. In many battery-powered circuits, the OP490
can be continuously operated for hundreds of hours before
requiring battery replacement, reducing equipment downtime,
and operating costs.
GND
+18V
Figure 2. Burn-In Circuit
+15V
+15V
1/4
OP490A
OP37A
V2
1k⍀
3
2
1
0
100⍀
–15V
VIN
250
500
750
HOURS
1000
1500
1750
Figure 4. Lithium-Sulphur Dioxide Cell Discharge Characteristic with OP490 and 100 kW Loads
requirement of the OP490, combined with the flat discharge
characteristic of the lithium cell, indicates that the OP490 can
be operated over the entire useful life of the cell. Figure 4 shows
the typical discharge characteristic of a 1 Ah lithium cell powering an OP490 with each amplifier, in turn, driving full output
swing into a 100 kW load.
–15V
1/4
OP490B
V1
20V p-p @ 10Hz
1/4
OP490C
0
10k⍀
CHANNEL SEPARATION = 20 LOG
1/4
OP490D
V1
V2/1000
Single-Supply Output Voltage Range
In single-supply operation the OP490’s input and output ranges
include ground. This allows true “zero-in, zero-out” operation.
The output stage provides an active pull-down to around 0.8 V
above ground. Below this level, a load resistance of up to 1 MW
to ground is required to pull the output down to zero.
In the region from ground to 0.8 V, the OP490 has voltage gain
equal to the data sheet specification. Output current source
capability is maintained over the entire voltage range including
ground.
Input Voltage Protection
Figure 3. Channel Separation Test Circuit
REV. C
The OP490 uses a PNP input stage with protection resistors in
series with the inverting and noninverting inputs. The high
breakdown of the PNP transistors coupled with the protection
resistors provides a large amount of input protection, allowing
the inputs to be taken 20 V beyond either supply without damaging the amplifier.
–9–
OP490
output of A is a triangle wave with upper and lower levels of
3.33 V and 1.67 V. The output of B is a square wave with almost
rail-to-rail swing. With the components shown, frequency of
operation is given by the equation:
Micropower Voltage-Controlled Oscillator
An OP490 in combination with an inexpensive quad CMOS
switch comprise the precision VCO of Figure 5. This circuit
provides triangle and square wave outputs and draws only 75 mA
from a 5 V supply. A acts as an integrator; S1 switches the
charging current symmetrically to yield positive and negative
ramps. The integrator is bounded by B which acts as a Schmitt
trigger with a precise hysteresis of 1.67 V, set by resistors R5,
R6, and R7, and associated CMOS switches. The resulting
fOUT = VCONTROL (Volts) ¥ 10 Hz / V
but this is easily changed by varying C1. The circuit operates
well up to a few hundred hertz.
C1
75nF
+5V
+5V
R1
200k⍀
2
R5
200k⍀
4
1
VCONTROL
3
11
R2
200k⍀
7
1/4
OP490E
A
R4
200k⍀
R3
100k⍀
6
5
SQUARE
OUT
1/4
OP490E
B
TRIANGLE
OUT
+5V
+5V
IN/OUT
VDD
1
14
R8
200k⍀
R6
200k⍀
R7
200k⍀
S1
OUT/IN
CONT
2
13
OUT/IN
3
S2
IN/OUT
CONT
12
IN/OUT
4
11
CONT
5
S3
OUT/IN
10
+5V
OUT/IN
CONT
6
9
S4
7
VSS
IN/OUT
8
Figure 5. Micropower Voltage Controlled Oscillator
–10–
REV. C
OP490
(ª10 kW) independent of the digital input code. The output
amplifiers act as buffers to avoid loading the DACs. The 100 kW
resistors ensure that the OP490 outputs will swing below 0.8 V
when required.
Micropower Single-Supply Quad Voltage-Output 8-Bit DAC
The circuit of Figure 6 uses the DAC8408 CMOS quad 8-bit
DAC, and the OP490 to form a single-supply quad voltage-output
DAC with a supply drain of only 140 mA. The DAC8408 is used
in voltage switching mode and each DAC has an output resistance
+5V
4
2
4
REFERENCE
VOLTAGE
1.5V
1
IOUT1A
DAC A
1/4
DAC8408
5
VREFA
VOUTA
2
2
1/4
OP490E
A
R1
100k⍀
11
IOUT2A/2B
6
7
6
IOUT1B
DAC B
1/4
DAC8408
VREFB
VOUTB
8
5
1/4
OP490E
B
R2
100k⍀
13
25
14
IOUT1C
DAC C
1/4
DAC8408
24
VREFC
VOUTC
27
IOUT2C/2D
12
1/4
OP490E
C
R3
100k⍀
9
8
23
IOUT1D
DAC 21
D
1/4
DAC8408
VREFD
VOUTD
21
10
1/4
OP490E
D
OP490EY
DAC DATA BUS
PIN9(LSB) – 16(MSB)
17
A/B
18
DIGITAL
CONTROL
SIGNALS
R/W
19
20
DAC8408ET
DS1
DS2
DGND
28
Figure 6. Micropower Single-Supply Quad Voltage Output 8-Bit DAC
REV. C
–11–
R4
100k⍀
OP490
R5
5k⍀
R2
9k⍀
+15V
R1
1k⍀
2
4
1/4
OP490E
B
R3
50⍀
1
VIN
R6
5k⍀
9
R7
50⍀
8
3
10
11
–15V
6
1/4
OP490E
C
1/4
OP490E
B
R4
50⍀
7
RL
R8
50⍀
5
13
14
1/4
OP490E
D
12
Figure 7. High Output Amplifier
High Output Amplifier
The amplifier shown in Figure 7 is capable of driving 25 V p-p
into a 1 kW load. Design of the amplifier is based on a bridge
configuration. A amplifies the input signal and drives the load
with the help of B. Amplifier C is a unity-gain inverter which
drives the load with help from D. Gain of the high output amplifier
with the component values shown is 10, but can easily be changed
by varying R1 or R2.
where n equals the decimal equivalent of the 8-bit digital code
present at the DAC. If the digital code present at the DAC
consists of all zeros, the feedback loop will be open causing the
op amp output to saturate. The 10 MW resistors placed in parallel with the DAC feedback loop eliminates this problem with a
very small reduction in gain accuracy. The 2.5 V reference biases
the amplifiers to the center of the linear region providing maximum
output swing.
Single-Supply Micropower Quad Programmable Gain Amplifier
The combination of quad OP490 and the DAC8408 quad 8-bit
CMOS DAC, creates a quad programmable-gain amplifier with
a quiescent supply drain of only 140 mA. The digital code present
at the DAC, which is easily set by a microprocessor, determines
the ratio between the fixed DAC feedback resistor and the resistance of the DAC ladder presents to the op amp feedback loop.
Gain of each amplifier is:
VOUT
256
=VIN
n
–12–
REV. C
OP490
VDD
3
VINA
+5V
1
RFBA
4
VREFA
C1
0.1␮F
2
IOUT1A 4
R1
10M⍀
DAC A
1/4
DAC8408
2
1
3
IOUT2A/2B 5
7
VINB
1/4
OP490E
A
VOUTA
11
RFBB
VREFB 8
C2
0.1␮F
DAC B
1/4
DAC8408
R2
10M⍀
IOUT1B 6
6
7
5
25
VINC
RFBC
VREFC
C3
0.1␮F
27
IOUT1C 25
R3
10M⍀
DAC C
1/4
DAC8408
9
8
10
IOUT2C/2D 24
22
VIND
VOUTB
1/4
OP490E
B
VOUTC
1/4
OP490E
C
RFBD
VREFD 21
C4
0.1␮F
DAC D
1/4
DAC8408
R4
10M⍀
IOUT1D 23
13
14
12
DAC DATA BUS
PIN9(LSB) – 16(MSB)
VOUTD
1/4
OP490E
D
17
A/B
18
DIGITAL
CONTROL
SIGNALS
R/W
19
20
OP490EY
DAC8408ET
+2.5V
REFERENCE
VOLTAGE
DS1
DS2
DGND
28
Figure 8. Single-Supply Micropower Quad Programmable Gain Amplifier
REV. C
–13–
OP490
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
14-Lead Plastic DIP
(P Suffix)
14-Lead Hermetic DIP
(Y Suffix)
0.005 (0.13) MIN 0.098 (2.49) MAX
14
8
PIN 1
1
7
0.100 (2.54) BSC
0.785 (19.94) MAX
0.200 (5.08)
MAX
0.200 (5.08)
0.125 (3.18)
0.023 (0.58)
0.014 (0.36)
0.795 (20.19)
0.725 (18.42)
0.310 (7.87)
0.220 (5.59)
14
0.320 (8.13)
0.290 (7.37)
PIN 1
0.060 (1.52)
0.015 (0.38)
0.150
(3.81)
MIN
0.070 (1.78) SEATING
PLANE
0.030 (0.76)
8
7
1
0.060 (1.52)
0.015 (0.38)
0.210 (5.33)
MAX
0.130
(3.30)
0.160 (4.06)
MIN
0.115 (2.93)
0.022 (0.558) 0.070 (1.77) SEATING
PLANE
0.014 (0.356) 0.045 (1.15)
0.015 (0.38)
0.008 (0.20)
15
0
0.100 (2.54)
BSC
0.280 (7.11)
0.240 (6.10)
0.325 (8.25)
0.300 (7.62)
0.195 (4.95)
0.115 (2.93)
0.015 (0.381)
0.008 (0.204)
16-Lead SOIC
(S Suffix)
0.4133 (10.50)
0.3977 (10.00)
9
16
0.2992 (7.60)
0.2914 (7.40)
PIN 1
0.4193 (10.65)
0.3937 (10.00)
8
1
0.050 (1.27)
BSC
0.0118 (0.30)
0.0040 (0.10)
0.1043 (2.65)
0.0926 (2.35)
8ⴗ
0.0192 (0.49) SEATING
0ⴗ
0.0125 (0.32)
PLANE
0.0138 (0.35)
0.0091 (0.23)
0.0291 (0.74)
ⴛ 45ⴗ
0.0098 (0.25)
0.0500 (1.27)
0.0157 (0.40)
Revision History
Location
Page
Data Sheet changed from REV. B to REV. C.
Deleted 28-Pin LCC (TC-Suffix) PIN CONNECTION DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Deleted ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Edits to ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Edits to ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
–14–
REV. C
–15–
–16–
PRINTED IN U.S.A.
C00308–0–4/02(C)