一种应用于TCXO的带隙基准源设计

Design of a Bandgap Reference Used in TCXO

采用CSMC 0.35μm混合工艺设计了一种应用于温度补偿晶体振荡器（TCXO）的低功耗带隙基准电压源和电压转换电路.可提供可调的多种参考电压,同时设计了启动与逻辑控制电路,确保基准电路能正常工作并降低功耗.Cadence Spectre仿真结果显示,采用3 V的电源电压,在-40℃~85℃范围内温度系数为14.5 ppm/℃,电源电压大于2.2 V即可正常启动,在正常工作情况下,基准功耗小于10μW,低频电源抑制比为83.2 dB.

A low power CMOS bandgap voltage reference circuit used in the temperature compensated crystal oscillator（TCXO） has been designed using CSMC 0.35 μm mixed process.The voltage transform circuit at the output stage is used as a buffer to provide various tunable reference voltages.The start-up circuit and the logic control circuit have also been designed,ensuring the proper function and power reduction of the reference circuit.Simulation results using Cadence Spectre indicate that at a supply voltage of 3 V,the average measured temperature coefficient is 14.5 ppm/℃ in the temperature range of-40℃ to 85℃.The circuit can be started up at a supply voltage greater than 2.2 V.Under normal working conditions,the power dissipation is less than 10 μW and the power supply rejection ratio is about 83.2 dB.