一种用于磁隔离驱动电路的编解码方案设计

Design of An Codec Scheme for Magnetic Isolation Drive Circuit

采用体硅0.25μm BCD工艺,设计了一种用于磁隔离驱动电路的编解码方案,将需要传输的数字信号编码成两个不同宽度的高频脉冲,这些高频脉冲从变压器初级线圈耦合到次级线圈,并且由次级端电路检测,最后在输出端重新恢复成输入的信号.相对于传统的磁隔离驱动电路的编解码方案,本文设计的磁隔离驱动电路的编码和解码方式新颖,电路实现简单,使传输的信号延迟时间大大减小,并且工作频率更高.仿真结果表明,电路在3~5V的电压下能正常工作,可以实现最大数据隔离传输速率达到125 Mbps,延迟时间最大仅有8ns,静态电流1.64mA,动态功耗0.37mA/Mbps.

Based on bulk silicon 0.25μm BCD process,a codec scheme for magnetic isolation drive circuit is designed.The digital signal to be transmitted is encoded into two high-frequency pulses with different widths.The primary winding of the transformer is coupled to the secondary winding and is detected by the secondary side circuit and finally restored to the input signal at the output.Compared with the codec scheme for traditional magnetic isolation drive circuit,the magnetic isolation drive circuit designed in this paper has a novel encoding and decoding method,and the circuit is simple to be realized.The delay time of the transmitted signal is greatly reduced and the frequency is higher.The simulation results show that the circuit can work normally under the voltage of 3-5 V,which can achieve the maximum data isolation transfer rate of 125 Mbps.The maximum delay time is only 8 ns,and the quiescent current is 1.64 mA with the dynamic power of 0.37 mA/Mbps.