OP77EJ(RevC) Ver la hoja de datos (PDF) - Analog Devices

Número de pieza

componentes Descripción

Fabricante

OP77EJ
(Rev.:RevC)

Next Generation OP07 Ultralow Offset Voltage Operational Amplifier

Analog Devices 

APPLICATIONS INFORMATION

+15V

R2

1M⍀

0.1␮F

R1

2

7

1k⍀

OP77E 6

R3

3

1k⍀

4

0.1␮F

R4

1M⍀

–15V

Figure 7. Precision High-Gain Differential Amplifier

The high gain, gain linearity, CMRR, and low TCVos of the

OP77 make it possible to obtain performance not previously

available in single-stage very high-gain amplifier applications.

For best CMR,

R1

R2

must equal

R3

R4

.

In

this

example,

with a 10 mV differential signal, the maximum errors are as listed

in Table I.

Table I. Maximum Errors

TYPE

COMMON-MODE VOLTAGE

GAIN LINEARITY, WORST CASE

TCVOS

TCI OS

AMOUNT

0.01%/V

0.02%

0.003%/∞C

0.008%/∞C

Bilateral Current Source

R3

1k⍀

OP77

R1

VIN

100k⍀

R2

100k⍀

2

OP77 6

3

R4

990⍀

IOUT < 15mA

R5

10⍀

Figure 9. Basic Current Source

R3

+15V

R1

VIN

R2

2

OP77 6

3

2N2222

2N2907

R5

R4

–15V

IOUT < 100mA

( ) R3

IOUT = VIN R1 – R5

GIVEN R3 = R4 ؉ R5, R1 = R2

Figure 10. 100 mA Current Source

These current sources will supply both positive and negative

current into a grounded load.

Note that

ZO

=

R5

ÊËÁ

R4

R2

+

1ˆ¯˜

R5 + R4 R3

R2 R1

and that for ZO to be infinite,

RS

INPUT

RF

10pF

+15V

0.1␮F

2

7

OP77 6

3

4

0.1␮F

100⍀

OUTPUT

CLOAD

–15V

Figure 8. Isolating Large Capacitive Loads

This circuit reduces maximum slew-rate but allows driving

capacitive loads of any size without instability. Because the boon

resistor is inside the feedback loop, its effect on output imped-

ance is reduced to insignificance by the high open-loop gain

of the OP77.

REV. C

–11–

Share Link: