基于自偏置结构的参考电流源电路

Reference Current Source Circuit Based on Self-Bias Structure

在传统参考电流源的基础上,设计了一种结构更为简单,与电源电压、温度无关的参考电流源,并在此基础上进一步优化了自偏置电路镜像电流的精度,更好地提高整个电路的性能。该电路基于SMIC 0.18μm BCD CMOS工艺,使用Cadence仿真软件进行电路仿真。结果表明,在-55~125℃的温度范围内,该电路的输出电流变化不超过3%,并且优化后的电流源镜像精度也得到了大幅度的提高。

Based on traditional reference current source, a reference current source with simpler structure independent of supply voltage and temperature is designed. Additionally, the accuracy of the mirror current is optimized to improve the performance of the whole circuit. The circuit is manufactured in SMIC 0.18 μm BCD CMOS process and simulated by Cadence. The results show that the output current of the circuit changes less than 3% in the temperature range of-55 ℃ to 125 ℃. The mirror accuracy of the optimized current source is also greatly improved.