Method for adjusting operational amplifier input offset voltage in automobile fuel injection system

Abstract

The invention relates to a method for adjusting operational amplifier input offset voltage in an automobile fuel injection system. The method is characterized in that the characteristic that a suspended grid electrode stores electric charges is utilized, enough voltage is added to a drain electrode and a grid electrode of a metal oxide semiconductor (MOS) transistor, a certain amount of electric charges are programmed on the suspended grid electrode, and threshold voltage of the transistor is adjusted; the voltage applied to the suspended grid electrode is improved or reduced as required, and the transistor conducts electricity normally. According to the method, after the adjustment, the input offset voltage of an operational amplifier is smaller than 500 microvolts.

Description

technical field [0001] The invention relates to a method for adjusting the input offset voltage of an operational amplifier in an automobile fuel injection system, and more precisely relates to a method for correcting the input offset voltage of a high-level operational amplifier in which a suspension grid is used in an automobile fuel injection system. It belongs to the field of circuit design. Background technique [0002] In the past few years, the mainstream products of domestic automotive electronics companies were only some low-tech automotive electronics products. In recent years, with the improvement of energy conservation and environmental protection awareness, automotive electronics technology has been increasingly adopted by low-end cars Domestic auto electronics companies have also begun to produce automotive electronic control systems such as automotive electronic fuel injection systems, anti-lock braking systems, and airbags. Products, the market share is cons...

AI Technical Summary

Problems solved by technology

Laser correction technology can achieve good correction accuracy, but the equipment is expensive, and there is no such equipment in the mainland at present; fuse correction technology requires probe detection points, occupies a large chip area, and the correction process is susceptible to electromagnetic interference, and the correction accuracy is relatively low , so it is not suitable for the correction of high-precision operational amplifiers; EEPROM correction technology can be corrected after packaging, which can achieve high correction accuracy, but the requirements for integrated circuit production technology are high, and it needs to be compatible with analog circuit technology and EEPROM technology. Such a process is immature, and the cost is relatively high, so it is not suitable for the production of high-precision operational amplifiers.

Images