High Precision, Low Noise

OPERATIONAL AMPLIFIERS

FEATURES

q LOW NOISE: 3nV/

√Hz

q WIDE BANDWIDTH:

OPA227: 8MHz, 2.3V/

OPA228: 33MHz, 10V/

q SETTLING TIME: 5

(significant improvement over OP-27)

q HIGH CMRR: 138dB

q HIGH OPEN-LOOP GAIN: 160dB

q LOW INPUT BIAS CURRENT: 10nA max

q LOW OFFSET VOLTAGE: 75

q WIDE SUPPLY RANGE:

q OPA227 REPLACES OP-27, LT1007, MAX427

q OPA228 REPLACES OP-37, LT1037, MAX437

q SINGLE, DUAL, AND QUAD VERSIONS

APPLICATIONS

q DATA ACQUISITION

q TELECOM EQUIPMENT

q GEOPHYSICAL ANALYSIS

q VIBRATION ANALYSIS

q SPECTRAL ANALYSIS

q PROFESSIONAL AUDIO EQUIPMENT

q ACTIVE FILTERS

q POWER SUPPLY CONTROL

OPA

4227

OPA227

OPA2

27

OPA

2227

OPA4

227

OPA2

227

DESCRIPTION

The OPA227 and OPA228 series op amps combine low

noise and wide bandwidth with high precision to make them

the ideal choice for applications requiring both ac and preci-

sion dc performance.

The OPA227 is unity-gain stable and features high slew rate

(2.3V/

µs) and wide bandwidth (8MHz). The OPA228 is opti-

mized for closed-loop gains of 5 or greater, and offers higher

speed with a slew rate of 10V/

µs and a bandwidth of 33MHz.

The OPA227 and OPA228 series op amps are ideal for

professional audio equipment. In addition, low quiescent

current and low cost make them ideal for portable applica-

tions requiring high precision.

The OPA227 and OPA228 series op amps are pin-for-pin

replacements for the industry standard OP-27 and OP-37

with substantial improvements across the board. The dual

and quad versions are available for space savings and per-

channel cost reduction.

The OPA227, OPA228, OPA2227, and OPA2228 are

available in DIP-8 and SO-8 packages. The OPA4227 and

OPA4228 are available in DIP-14 and SO-14 packages

with standard pin configurations. Operation is specified

from –40

°C to +85°C.

SPICE model available for OPA227 at www.ti.com

SBOS110A – MAY 1998 – REVISED JANUARY 2005

www.ti.com

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

Copyright © 1998-2005, Texas Instruments Incorporated

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.

OPA227

OPA2227

OPA4227

OPA228

OPA2228

OPA4228

1

2

3

4

8

7

6

5

Trim

V+

Output

NC

Trim

–In

+In

V–

OPA227, OPA228

DIP-8, SO-8

NC = Not Connected

1

2

3

4

8

7

6

5

V+

Out B

–In B

+In B

Out A

–In A

+In A

V–

OPA2227, OPA2228

DIP-8, SO-8

A

B

1

2

3

4

5

6

7

14

13

12

11

10

9

8

Out D

–In D

+In D

V–

+In C

–In C

Out C

Out A

–In A

+In A

V+

+In B

–In B

Out B

OPA4227, OPA4228

DIP-14, SO-14

AD

BC