A Two-Pin Trimming Circuit with Pre-trimming Function

In actual production, due to the influence of the manufacturing process, there will be some deviations between the actual parameters and the design values of the chip, which will affect the performance of the chip. Based on the above problems, a two-pin trimming circuit design with pre-trimming function is proposed. This paper introduces the main characteristics, implementation process and coding protocol of the trimming circuit. Compared with the traditional trimming circuit, the pre-trimming function can determine the better trimming scheme. During the final trimming, multiple fuses can be melted at one time without repeated operation. The design of the ending fuse can avoid the problem of fuse melting by mistake that caused by signal fluctuation after trimming. The design of the chip is based on 30V 0.18$\mu{\mathrm {m}}$ BCD process, and the simulation results show that the design can meet the expected requirements.