A 11.3-ppm/°C, Two Temperature Points Trimmed Current Generator for Precise RC Oscillators

This paper presents a current generator with trimmed temperature coefficient (TC) to achieve stability over a large temperature range. The proposed circuit is based on the V T -multiplier combined with a metal resistor for temperature compensation and utilizes digital resistor trimming for TC and output current calibration. The circuit has been designed at the transistor level and extensively simulated in a 180-nm BiCMOS process. Simulation results show less than 1% corner and mismatch variation of the nominal $10-\boldsymbol{\mu}\mathbf{A}$ output current and a remarkably low 11.3-ppm/°C residual temperature coefficient over the range from −40 to 135 °C.