|
5962-8773802GA Datasheet, PDF (10/16 Pages) Analog Devices – Next Generation OP07 Ultralow Offset Voltage Operational Amplifier | |||
|
◁ |
OP77
TEST CIRCUITS
200kâ¦
50â¦
OP77
VO
VOS
=
VO
4000
Figure 21. Typical Offset Voltage Test Circuit
100â¦
100â¦
2.5Mâ¦
V+
2
7
OP77
3
4
6 3.3kâ¦
4.7µF
OUTPUT
(â10Hz FILTER)
Vâ
INPUT REFERRED NOISE = VO
25,000
Figure 22. Typical Low-Frequency Noise Test Circuit
â
INPUT
+
20kâ¦
1
2
8
OP77 7 6
3
4
V+
OUTPUT
Vâ
Figure 23. Optional Offset Nulling Circuit
100kâ¦
+18V
*
+
10µF
10â¦
10kâ¦
2
0.1µF
7
OP77 6
3
4
10kâ¦
10â¦
0.1µF
* 10µF
+
â18V
NOTES
*1 PER BOARD
Figure 24. Burn-In Circuit
10kâ¦
100kâ¦
1Mâ¦
VIN = ±10V
10â¦
TYPICAL PRECISION
OP AMP
VY
VX
RL
â10V
VX
0V
+10V
NOTES
AVO 650V/mV
RL = 2kâ¦
1. GAIN NOT CONSISTANT. CAUSES NONLINEAR ERRORS.
2. AVO SPEC IS ONLY PART OF THE SOLUTION.
3. CHECK SPECIFICATION TABLE 1 AND TABLE 2 FOR PERFORMANCE.
Figure 25. Open-Loop Gain Linearity
Actual open-loop voltage gain can vary greatly at various output
voltages. All automated testers use endpoint testing and therefore
only show the average gain. This causes errors in high closed-
loop gain circuits. Because this is difficult for manufacturers to
test, users should make their own evaluations. This simple test
circuit makes it easy. An ideal op amp would show a horizontal
scope trace.
VY
â10V
0V
+10V
VX
Figure 26. Output Gain Linearity Trace
This is the output gain linearity trace for the new OP77. The
output trace is virtually horizontal at all points, assuring
extremely high gain accuracy. The average open-loop gain is
truly impressiveâapproximately 10,000,000.
Rev. E | Page 10 of 16
|
▷ |