LT1028 - Ultra Low Noise Precision High Speed Op Amps

The LT1028 (gain of –1 stable)/LT1128(gain of +1 stable) achieve a new standard of excellence in noise performance with 0.85nV/Rt.Hz 1kHz noise, 1.0nV/Rt.Hz 10Hz noise. This ultralow noise is combined with excellent high speed specifications (gain-bandwidth product is 75MHz for LT1028, 20MHz for LT1128), distortion-free output, and true precision parameters (0.1µV/°C drift, 10µV offset voltage, 30 million voltage gain). Although the LT1028/LT1128 input stage operates at nearly 1mA of collector current to achieve low voltage noise, input bias current is only 25nA.

The LT1028/LT1128’s voltage noise is less than the noise of a 50 Ohm resistor. Therefore, even in very low source impedance transducer or audio amplifier applications, the LT1028/LT1128’s contribution to total system noise will be negligible.

  • Voltage Noise 1.1nV/rt Hz Max. at 1kHz 0.85nV/rt Hz Typ. at 1kHz 1.0nV/ rtHz Typ. at 10Hz
  • 35nVP-P Typ., 0.1Hz to 10Hz
  • Gain-Bandwidth Product LT1028: 50MHz Min. LT1128: 13MHz Min.
  • Slew Rate LT1028: 11V/µs Min. LT1128: 5V/µs Min.
  • Offset Voltage: 40µV Max.
  • Drift with Temperature: 0.8µV/°C Max.
  • Voltage Gain: 7 Million Min.
  • Voltage and Current Noise 100% Tested
  • Available in 8-Pin SO Package
Typical Application
LT1028 Typical Application
LT1028 Typical Application
  • Low Noise Frequency Synthesizers
  • High Quality Audio
  • Infrared Detectors
  • Accelerometer and Gyro Amplifiers
  • 350 ohms Bridge Signal Conditioning
  • Magnetic Search Coil Amplifiers
  • Hydrophone Amplifiers
LT1028 Package Drawing
LT1028 Package Drawing
Order Information
Part NumberPackageTempPrice(1-99)Price (1k)*
Demo Boards
Part NumberDescriptionPrice
DC417BDIP8, MS8, S8, SOT23-6 | Multi-Footprint General Purpose Board for Single Op. Amp$25.00
Application Note
Design Note
Reliability Data
Product Selector Card
LT Journal
CAD Symbol
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LT1028 Footprints and Symbols
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