A 16~21GHz 5-Bit High-Accuracy Attenuator

A high-precision 5-bit digital attenuator is designed for phased array system. In the small attenuation bit circuit, a simplified T-type attenuation structure is used to reduce the insertion loss, and the small attenuation bit is designed to be continuously adjustable to reduce the attenuation error and improve the attenuation accuracy. The π-type attenuation structure is used to design the large attenuation bit circuit, and the large attenuation bit is divided into two ends of the circuit to compensate for the return loss. At the same time, the tail capacitor compensation structure is used to reduce the additional phase shift of each attenuation unit. Post-simulation results show that the attenuator operates at 16~21 GHz and achieves an attenuation step of 0.5 dB and an attenuation range of 15.5 dB, with an insertion loss of less than 4.5 dB, an attenuation error of less than 0.082 dB, and an additional phase shift of less than ±3.55°.