Special Constant Current Source for Magnetic Field of Measuring System of Planck's Constant
Bing Han · Electrical Measurement & Instrumentation · 2011
A constant current source with high stability is required in establishing measuring system of Planck's constant.The technique based on series compensation type for special constant current source for magnetic field was described.Therewith the constant current source with 4.5×10-6/30min stability was constructed through designing the extraordinary sampling resistor,selecting stable voltage reference and operational amplifier with outstanding properties,offsetting the phase shift of inductive load.As a special constant current source for magnetic field,it presently could serve for the measuring system of Planck's constant.