Second-Order Temperature-Compensated Total-Current Reference

This paper describes the study of a simple two-branch current reference where the sum of branch currents (that is, the total current) is compensated with temperature. This approach is the most adequate when the reference must supply current in a charge with grounded or connected to voltage-supply end. The second-order thermal compensation of the reference current is analyzed here. The equation representing the total-current compensation condition is deduced. The current reference is designed in a CMOS 0.35μm process and his quality has been verified by computer simulation. The simulation results show the possibility of achieving good performances: a complete variation smaller than 0.45%, for a total current of 8...15μA, across a temperature range of 0 100 o C. The first-order temperature-compensated total-current reference does the object of another paper, submitted in the same Conference. Key-Words: analog integrated circuits, reference current source, temperature compensation