OP77AJMDA AD [Analog Devices], OP77AJMDA Datasheet - Page 12

• Manufacturer Part Number: OP77AJMDA
• Description: Next Generation OP07 Ultralow Offset Voltage Operational Amplifier
• Manufacturer: AD [Analog Devices]

OP77
Precision Current Sinks
These simple high-current sinks require the load to float between
the power supply and the sink.
The high gain and low TCV
inputs from microvolts to volts. In this circuit, the signal always
R
5
V
V
R
+
IN
IN
2
R
4
must =
Figure 12. Positive Current Source
Figure 11. Positive Current Sink
OP77
OP77
V
R
R
IN
3
1
200
OS
200
2
3
assure accurate operation with
OP77E
+15V
–15V
V+
IRF520
R
1
1W
R1
7
4
L
I
O
0.1 F
0.1 F
6
Figure 14. Precision Absolute Value Amplifier
V–
IRF520
R
FULL SCALE OF 1V,
I
V
I
I
O
L
O
O
R1
IN
=
=
> OV
V
R1
1A/V
IN
30pF
C1
V
I
O
IN
=
> OV
V
R1
IN
D1
1N4148
–12–
2N4393
1k
In these circuits, OP77’s high gain, high CMRR, and low TCV
ensure high accuracy.
This simple bootstrapped voltage reference provides a precise 10 V
virtually independent of changes in power supply voltage, ambi-
ent temperature and output loading. Correct Zener operating
current of exactly 2 mA is maintained by R1, a selected 5 ppm/∞C
resistor, connected to the regulated output. Accuracy is prima-
rily determined by three factors: the 5 ppm/∞C temperature
coefficient of D1, 1 ppm/∞C ratio tracking of R2 and R3, and
operational amplifier V
VOs errors, amplified by 1.6 (AVCL), appear at the output and
can be significant with most monolithic amplifiers. For example,
an ordinary amplifier with TCV
∞C of output error while the OP77, with TCV
contributes but 0.05 ppm/∞C of output error, thus effectively
eliminating TCV
The high gain and low TCV
inputs from microvolts to volts. In this circuit, the signal always
appears as a common-mode signal to the op amps. The OP77E
CMRR of 1 V/V assures errors of less than 2 ppm.
D2
2k
R3
6.4V
1N4579A
5ppm/ C
2
3
Figure 13. High Stability Voltage Reference
5%
OP77E
+15V
–15V
D1
7
4
0.1 F
0.1 F
2mA
1k
OS
6
as an error consideration.
1.8k
OS
R1
errors.
3
2
OS
OP77
OS
assure accurate operation with
4
of 5 mV/∞C contributes 0.8 ppm/
7
15V
V
0 < V
OUT
6
OUT
< 10V
R2
3.6k
R3
6.4k
OS
of 0.3 mV/∞C,
A
VCL
E
O
= 10V
REV. C
1.6
OS