A High Precision Analog Temperature Compensated Crystal Oscillator Using a New Temperature Compensated Multiplier

The development and application of various precision electronic devices require a large number of high-precision and low-cost temperature-compensated crystal oscillators (TCXO) to generate frequency references. In order to achieve higher compensation accuracy at lower cost, a new fully integrated analog-TCXO (ATCXO) is proposed in this paper. It uses an innovative temperature-compensated multiplier to generate cubic and quintic voltages. The experimental results show that it can achieve the ultra-high fitting of the frequency-temperature characteristic curve of the crystal. This effectively improves the compensation accuracy of the TCXO. The proposed ATCXO achieves a frequency stability of +/- 0.8 ppm in the temperature range of -40 degrees C to 95 degrees C. At the same time, the gain-temperature error of the proposed temperature compensated analog multiplier is <= 0.13 dB. This paper is based on SMIC 130 nm process, the core area of the chip is only 0.124 mm(2) . Multiple modules such as bandgap circuit, n-th power voltage generation circuit, summation circuit, gain control circuit and voltage controlled oscillator using variable capacitor array are integrated.