一种用于非屏蔽SERF态原子磁强计的电流源设计

摘要

设计了一种用于非屏蔽SERF态原子磁强计的电流源.利用运算放大器和MOSFET构建基本的电流负反馈V/I转换电路,采用高性能元器件降低输出电流纹波,并通过频率补偿的方法使电路稳定.测试结果表明:在恒负载的条件下,电流源的输出范围为0～500 mA,纹波电流小于30.5μA,对应磁场的稳定性优于10 nT,满足非屏蔽情况下原子磁强计利用磁补偿制备SERF态的要求.%A current source is proposed for unshielded atomic magnetometer based on spin-exchange relaxation free( SERF) regime. It uses operational amplifier and MOSFET to construct basic V/I change-over circuit, and high-performance components is used to reduce the ripple of output current, then stablizes the circuit by frequency compensation method. The test results show that the current source output range 0~500 mA,and the ripple current is less than 30.5 μA when the load is invariable, the stability of corresponding magnetic field is prior to 10 nT, which meets the requirements of SERF regime atomic magnetometer for unshielded applications.