An Automotive Low-Power EMC Robust Brokaw Bandgap Voltage Reference

This article proposes an electromagnetic compatibility improved bandgap voltage reference with a low current consumption of only 3.5 μA in an automotive environment with a wide temperature range from -40 °C to 160 °C and a high electromagnetic interference (EMI) robustness. The proposed reference is based on the well-known Brokaw bandgap with only five bipolar transistors in the bandgap core including collector current leakage compensation. We analyzed parasitic effects in the bandgap core such as the influence of parasitic capacitances between the substrate and the collectors of these bipolar transistors as well as the impact of the operational amplifier. We made recommendations on how to improve the bandgap EMI robustness. Simulation results were compared with measurements on a test chip. The measurement results showed excellent EMI robustness.