Differential automatic zero-adjusting amplifier.
A method is described for building a low-voltage-drift differential dc amplifier featuring automatic zero adjustment, a high input impedance, and a bandwidth of 10 kHz. This is achieved by an asymmetric two-step process between the input signal and ground. Bandwidth can be extended by the use of a second amplifier during the ground-sampling time. The amplifier can be made with standard electronic components. A major advantage of this method is that an existing amplifier can easily be converted into a low-voltage-drift amplifier by adding the essential elements of the described automatic zero-adjusting amplifier to its input stage. To illustrate the method a practical example is constructed featuring a drift of 0.2 microV/ degrees C.
Broersen
B
B
Department of Animal Physiology, University of Amsterdam, Kruislaan 320, 1098 SM Amsterdam, The Netherlands.
Van Krevelen
F
F
van Heusden
J T
JT
van Heukelom
J S
JS
D000669:Amplifiers, Electronic; D001331:Automation; D004553:Electric Conductivity; D017097:Electric Impedance; D001330:Electronic Data Processing; D004581:Electronics; D004582:Electronics, Medical / Q000295:instrumentation*; D004867:Equipment Design; D013696:Temperature