Datasheet

Low Cost Precision Difet
®
OPERATIONAL AMPLIFIER
Difet
®
, Burr-Brown Corp.
BIFET
®
, National Semiconductor Corp.
OPA121
FEATURES
● LOW NOISE: 6nV/√Hz typ at 10kHz
● LOW BIAS CURRENT: 5pA max
● LOW OFFSET: 2mV max
● LOW DRIFT: 3
µV/°C typ
● HIGH OPEN-LOOP GAIN: 110dB min
● HIGH COMMON-MODE
REJECTION: 86dB min
Noise-Free
Cascode*
Ω10k
Trim
1
5
3
2
+In
–In
Case (TO-99) and Substrate
Output
OPA121 Simplified Circuit
+V
CC
–V
CC
8
7
6
4
2kΩ
Ω10k
2kΩ
2kΩ
2kΩ
*Patented
Trim
DESCRIPTION
The OPA121 is a precision monolithic dielectrically-
isolated FET (
Difet
®
) operational amplifier. Out-
standing performance characteristics are now
available for low-cost applications.
Noise, bias current, voltage offset, drift, open-loop
gain, common-mode rejection, and power supply
rejection are superior to BIFET
®
amplifiers.
Very low bias current is obtained by dielectric
isolation with on-chip guarding.
Laser-trimming of thin-film resistors gives very low
offset and drift. Extremely low noise is achieved with
new circuit design techniques (patented). A new
cascode design allows high precision input specifica-
tions and reduced susceptibility to flicker noise.
Standard 741 pin configuration allows upgrading of
existing designs to higher performance levels.
APPLICATIONS
● OPTOELECTRONICS
● DATA ACQUISITION
● TEST EQUIPMENT
● MEDICAL EQUIPMENT
● RADIATION HARD EQUIPMENT
®
International Airport Industrial Park • Mailing Address: PO Box 11400 • Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd. • Tucson, AZ 85706
Tel: [phone] • Twx: 910-952-1111 • Cable: BBRCORP • Telex: 066-6491 • FAX: [phone] • Immediate Product Info: [phone]
© 1984 Burr-Brown Corporation PDS-539F Printed in U.S.A. September, 1993
SBOS139