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Wide bandwidth constant current source for ac galvanomagnetic measurements.
1Department of Physics, Seton Hall University, South Orange, New Jersey 07079, USA.
The Review of Scientific Instruments
|November 1, 1979
Summary
A versatile constant current source using one op-amp is presented. This device offers a wide bandwidth and ground-floating capability, suitable for various electronic measurements.
Area of Science:
- Electronics
- Electrical Engineering
- Solid State Physics
Background:
- Accurate current sources are crucial for precise electronic measurements.
- Existing current sources may have limitations in bandwidth or grounding flexibility.
Purpose of the Study:
- To describe a simple, versatile one-operational amplifier (op-amp) constant current source.
- To highlight its key features and demonstrate its applicability in advanced measurement techniques.
Main Methods:
- Design and implementation of a single op-amp based constant current source circuit.
- Characterization of the source's bandwidth and ground-floating capabilities.
- Integration of the source into experimental setups for specific measurements.
Main Results:
- The developed constant current source exhibits a wide bandwidth (greater than or similar to 10 kHz).
- The source successfully floats from third-wire ground, enhancing measurement versatility.
- Demonstrated successful application in AC conductivity, Double-AC Hall effect, and tunneling measurements.
Conclusions:
- The one-op-amp constant current source is a highly versatile and effective instrument.
- Its wide bandwidth and ground-floating feature make it suitable for demanding electronic and physical measurements.
- This design offers a practical solution for researchers in various fields requiring precise current control.
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