A trimming circuit and battery protection chip

Abstract

The embodiment of the invention provides a trimming circuit. The circuit comprises a first voltage divider resistor and a second voltage divider resistor, wherein the first voltage divider resistor and the second voltage divider resistor are serially connected between a trimming voltage output end of the trimming circuit and a ground end; the connection point of the first voltage divider resistor and the second voltage divider resistor serves as a reference voltage input end of the trimming circuit; a first pad group, a first trimming unit and a first auxiliary trimming module in parallel connection are connected between the first voltage divider resistor and the trimming voltage output end; a second trimming unit and a second auxiliary trimming module in serial connection are connected between the second voltage divider resistor and the ground end; and a second pad group is in parallel connection with the second trimming unit and the second auxiliary trimming module in serial connection. By using match between an auxiliary trimming resistor and a switch transistor, the threshold trimming voltage of the trimming circuit is adjusted, consistency of a two-way trimming range of the threshold trimming voltage of over discharge protection voltage vod is ensured, and after accurate threshold voltage trimming of overcharge protection voltage voc, accurate threshold voltage trimming of the discharge protection voltage vod can also be realized.

Description

technical field [0001] This application relates to microelectronic technology, in particular, to a trimming circuit and a battery protection chip. Background technique [0002] Overcharge protection and overdischarge protection are one of the important functions of lithium battery protection. With the development of lithium battery protection chips, the requirements for overcharge protection and overdischarge protection thresholds are getting higher and higher. Therefore, trimming is usually added when designing protection chips. The circuit is used to adjust the threshold value deviation caused by technological reasons, so as to make the protection threshold value more accurate. Such as figure 1 As shown, the threshold trimming voltage V of the traditional trimming circuit is obtained by dividing the reference voltage vref, and the threshold trimming voltage V obtained is also different if the voltage dividing resistors Ru and Rd are different. [0003] In order to share ...

AI Technical Summary

Problems solved by technology

[0004] An embodiment of the present application provides a trimming circuit and a battery protection chip to solve the problem of the overcharge protection voltage voc when trimming the threshold of the overcharge protection voltage voc and the threshold of the overdischarge protection voltage vod in the prior art. After the threshold voltage trimming is accurate, the threshold voltage trimming of the over-discharge protection voltage vod is inaccurate

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