Integrating amplifiers using cooled JFETs

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

11

Jfet, Satellite-Borne Instruments, Transistor Amplifiers, Infrared Astronomy Satellite, Integrated Circuits, Metal Oxide Semiconductors

Scientific paper

It is shown how a simple integrating amplifier based on commercially available JFET and MOSFET switches can be used to measure photocurrents from detectors with noise levels as low as 1.6 x 10 to the -18th A/root Hz (10 electrons/sec). A figure shows the basic circuit, along with the waveform at the output. The readout is completely nondestructive; the reset noise does not contribute since sampling of the accumulated charge occurs between resets which are required only when the stored charge has reached a very high level. The storage capacity ranges from 10 to the 6th to 10 to the 9th electrons, depending on detector parameters and linearity requirements. Data taken with an Si:Sb detector operated at 24 microns are presented. The responsivity agrees well with the value obtained by Young et al. (1981) in the transimpedance amplifier circuit. The data are seen as indicating that extremely low values of NEP can be obtained for integration times of 1 sec and that longer integrations continue to improve the SNR at a rate faster than the square root of time when background noise is not present.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Integrating amplifiers using cooled JFETs does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Integrating amplifiers using cooled JFETs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Integrating amplifiers using cooled JFETs will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1368361

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.