Design and Analysis of High Stability, Low Noise Current Source

Key performance of high-stability current source, indicators such as output stability and noise spectrum within an extended bandwidth have become crucial determinants in precision measurement systems. This paper introduces a novel design of a Voltage Controlled Current Source (VCCS) featuring bipolar output. This design integrates a cascaded transistor push-pull configuration with a DC Current Transformer (DCCT) based current feedback circuit, enabling current outputs up to 2 A. Rigorous experimental evaluations have substantiated proficiency in delivering minimal current ripple, exceptional stability, and versatility in output power range. The apparatus exhibits peak noise at $2.3 \mu \mathrm{A} / \mathrm{Hz}^{1 / 2}$ at 50 Hz and statistical uncertainty of 0.38 ppm at 2 A.