**5. Conclusions**

This paper presents a 40 nm CMOS relaxation oscillator with low-current consumption. It features simple topology that comprises a two-transistor-based voltage reference generator and a simple current reference generator with a temperature-compensated composite resistor. Moreover, the comparators are designed with a CTAT delay to counteract the PTAT delay contributed by the effect of the leakage current in switches, thus improving the thermal stability of the output frequency.

The simulation results confirmed that the proposed ROSC displayed excellent output frequency stability against the changes in temperature and supply voltage. Therefore, the proposed work is suitable for low-power applications that require an oscillator with a stable frequency and moderate precision.

**Author Contributions:** Conceptualization, Y.L. and P.K.C.; methodology, Y.L. and P.K.C.; software, Y.L.; validation, Y.L. and P.K.C.; formal analysis, Y.L. and P.K.C.; investigation, Y.L. and P.K.C.; resources, P.K.C.; data curation, Y.L.; writing—original draft preparation, Y.L.; writing—review and editing, P.K.C.; visualization, Y.L.; supervision, P.K.C.; project administration, P.K.C. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Data Availability Statement:** The study did not report any data.

**Conflicts of Interest:** The authors declare no conflict of interest.
