中圖分類號：TN433 文獻(xiàn)標(biāo)志碼：A DOI: 10.16157/j.issn.0258-7998.244897
中文引用格式： 應(yīng)科煒. 一種車規(guī)級LED驅(qū)動芯片的電流檢測電路[J]. 電子技術(shù)應(yīng)用，2024，50(10)：24-29.
英文引用格式： Ying Kewei. Current monitoring circuit of automotive grade LED driver[J]. Application of Electronic Technique，2024，50(10)：24-29.

Current monitoring circuit of automotive grade LED driver

Abstract： A high precision LED current detection circuit is designed in order to meet the functional safety requirements of ISO 26262. Based on the traditional LED constant-current detection circuit, a negative feedback loop is added in the current mirror module to achieve accurate copy of the detection current, avoid the current sampling error in the traditional current detection circuit, and improve the accuracy of the current detection. At the same time, the new circuit adopts the structure of sampling block and power block in series, which reduces the occurrence of current miss detecting and expands the coverage of current detection. The LED current detection circuit is designed by SMIC 0.18 μm CMOS process. The test results show that the detection accuracy can reach ±1% in the range of 5 mA ~ 60 mA LED current.

Key words : automotive LED driver；output current detection；functional safety；negative feedback loop