A One-Point Exponential Trimming Technique for an Effective Suppression of Process Spread in BJT-based Temperature Processing Circuits

This paper presents a trimming technique to suppress the thermal effects of process spread of BJT-based temperature processing circuits. The proposed calibration method has the advantage of requiring a reading at a single temperature while compensating for the spread of the thermal behaviour of the base-to-emitter voltage of bipolar transistors; in addition to this, the effectiveness of the proposed technique is improved by an exponential approach carried out on the design of the trimming structure. The strength of the presented technique is shown to be effective on a 6-bit trimming circuit designed and extensively simulated in a standard 180-nm CMOS process; this implementation provides a reduction of the considered spread of about 90% making it suitable for a number of applications in which process variations limit the accuracy of the circuit.

Automated summary

This paper presents a trimming technique to suppress the thermal effects of process spread of BJT-based temperature processing circuits. The proposed method requires a single temperature reading and compensates for the spread of thermal behavior of bipolar transistors. The effectiveness of the technique is improved through an exponential approach in the design of the trimming structure.