[1] [1] SHYU Y S, WU J C. A process and temperature compensated ring oscillator ［C］ // IEEE Asia-Pacific Conference on ASIC (AP-ASIC). Cheju, Korea. 1999: 283-286.

[3] [3] DOCKING S, SACHDEV M. A method to derive an equation for the oscillation frequency of a ring oscillator ［J］. IEEE Transactions on Circuits and Systems-I: Fundamental Theory and Applications, 2003, 50(2): 259-264.

[4] [4] WEIGANDT T C. Low-phase-noise, low timing jitter design techniques for delay cell based VCOs and frequency synthesizers ［D］. City of Berkeley: University of California, 1998: 145-169.

[5] [5] WU S S, WANG C. Analysis and design of a linear voltage controlled ring oscillator with rail-to-rail tuning range and zero static power ［J］. International Journal of Electronics Letters, 2018, 7(4): 2168-1724.

[6] [6] HAZERI A R, MIAR-NAIMI H. Novel closed-form equation for oscillation frequency range of differential ring oscillator ［J］. Analog Integrated Circuits and Signal Processing, 2018, 96(1): 117-123.

[7] [7] MONDAL A J, TALUKDAR J, BHATTACHARYYA B K. Estimation of frequency and amplitude of ring oscillator built using current sources ［J］. Ain Shams Engineering Journal, 2020, 11(3): 677-686.

[8] [8] WANG Y, CHAN P K, LI K H. A compact CMOS ring oscillator with temperature and supply compensation for sensor applications ［C］ // IEEE Computer Society Annual Symposium on VLSI. Tampa, FL, USA. 2014: 267-272.

[9] [9] SOULIOTIS G, KERAMIDA E, Plessas F, et al. Temperature compensated ring oscillator based VCO ［J］. International Journal of Electronics and Communications, 2022, 149: 154195.