DESIGN OF A LOCK-IN AMPLIFIER,

Abstract

The lock-in amplifier is an instrument capable of measuring a periodic signal under adverse signal to noise conditions, i.e., RMS noise at least 20dB larger than the signal. A synchronous detector followed by a narrowband filter is used to give a dc voltage output which is proportional to the input signal amplitude. The design stresses simplicity. By using relatively inexpensive integrated circuits, preliminary testing indicated the performance could surpass existing standards. By using MOSFET chopper transistors in a series-shunt configuration the range of operating frequencies has been extended to 5 megahertz. The final unit is packaged in a 11 by 6 by 5 inch cabinet with a power supply. All operating conditions are met by using front panel controls and no external plug-in attachments are necessary. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1970
Accession Number
AD0705528

Entities

People

  • Lawrence C. Caplan

Organizations

  • University of California, Los Angeles

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Amplifiers
  • Amplitude
  • Attachment
  • Circuits
  • Detectors
  • Electronic Amplifier
  • Electronic Equipment
  • Electronics
  • Frequency
  • Integrated Circuits
  • Narrowband
  • Power Supplies
  • Semiconductor Devices
  • Solid State Electronics
  • Standards
  • Transistors

Fields of Study

  • Physics

Readers

  • Electrical Engineering
  • Electronics Engineering
  • Integrated Circuit Design and Technology.