ROMJIST Volume 22, No. 2, 2019, pp. 144-157
Cosmin-Sorin Plesa, Marius Neag, Cristian Mihai Boianceanu Design of Over-Temperature Protection for Switched-Capacitor DC-DC Converter Based on Electro-Thermal Simulations
ABSTRACT: This paper presents an over-temperature protection (OTP) circuit for a DC-DC converter based on switching capacitors (SC DC-DC). A two-steps design methodology was employed: a first-pass circuit was obtained by using standard, electrical-only simulations; next, electro-thermal simulations were employed to ascertain the best location of the thermal sensor and the resulting thermal coupling, thus allowing for the fine-tuning of the final circuit. The die temperature distribution was analyzed for two critical operational scenarios in order to identify the worst case and to provide design data for implementing a robust and precise OTP. The key electrical and electro-thermal simulation results are presented in some detail. Finally, results of measurement performed on the actual silicon are presented, to validate the design.KEYWORDS: Over-temperature protection; switched-capacitor DC-DC converter; controlled charging current, thermal shutdown; electro-thermal simulationsRead full text (pdf)