OPA128 Datasheet, PDF (1/11 Pages) Burr-Brown (TI) – Difet Electrometer-Grade OPERATIONAL AMPLIFIER

®
OPA128
Difet^® Electrometer-Grade
OPERATIONAL AMPLIFIER
FEATURES
q ULTRA-LOW BIAS CURRENT: 75fA max
q LOW OFFSET: 500µV max
q LOW DRIFT: 5µV/°C max
q HIGH OPEN-LOOP GAIN: 110dB min
q HIGH COMMON-MODE REJECTION:
90dB min
q IMPROVED REPLACEMENT FOR AD515
AND AD549
APPLICATIONS
q ELECTROMETER
q MASS SPECTROMETER
q CHROMATOGRAPH
q ION GAUGE
q PHOTODETECTOR
q RADIATION-HARD EQUIPMENT
DESCRIPTION
The OPA128 is an ultra-low bias current monolithic
operational amplifier. Using advanced geometry
dielectrically-isolated FET (Difet^®) inputs, this mono-
lithic amplifier achieves a performance level exceed-
ing even the best hybrid electrometer amplifiers.
Laser-trimmed thin-film resistors give outstanding volt-
age offset and drift performance.
A noise-free cascode and low-noise processing give
the OPA128 excellent low-level signal handling capa-
bilities. Flicker noise is very low.
The OPA128 is an improved pin-for-pin replacement
for the AD515.
Difet^® Burr-Brown Corp.
Case (Guard)
8
–In
2
3
+In
Noise-Free
Cascode
Trim _1kΩ
1
5
Trim ^1kΩ
28kΩ
2kΩ
28kΩ
2kΩ
OPA128 Simplified Circuit
7
+V_CC
6
Output
4
–V_CC
SBOS148
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
Internet: http://www.burr-brown.com/ • FAXLine: [phone] (US/Canada Only) • Cable: BBRCORP • Telex: 066-6491 • FAX: [phone] • Immediate Product Info: [phone]
©_{1986 Burr-Brown Corporation}
PDS-653E
Printed in U.S.A. May, 1995