Design of a Precise Current Source Circuit
Yan Liu · 2008
A precise current source circuit was proposed.In this circuit,the bandgap reference voltage independent of temperature and power supply was transformed into high-precision reference current independent of temperature and voltage by V-I converter,and the reference current was mirrored by an accurate current mirror.Adverse effects induced by changing temperature,power supply,and load impedance,as well as some disturbance factors, were avoided.Circuits before and after improvement were tested with HSPICE for comparison.Results showed that the current mirror error of the improved circuit was reduced by about 90%,and the precision of the current source circuit was significantly enhanced.