New Technique: A low drift current reference based on PMOS temperature correction technology
A low drift current reference based on PMOS temperature correction technology is proposed. To achieve the minimum temperature coefficient (TC), the PMOS cascode current mirror is designed as a cross structure. By exchanging the bias for two layers of the self-biased PMOS cascode structure, the upper PMOS, which is used to adjust the TC together with the resistor of the self-biased PMOS cascode structure, is forced to work in the linear region. As the proposed current reference is the on-chip current reference of a high voltage LED driver with high accuracy, it was designed using a CSMC 1 mu m 40 V BCD process. Simulation shows that the TC of the reference current was only 23.8x10(-6)/A degrees C over the temperature range of -40-120 A degrees C under the typical condition.
low drift current reference temperature coefficient pmos cascode cross structure