Abstract

This document was translated from a simplified Chinese source. (ZHCAG53)

BDC motors (brushed DC motors) are widely used in the home appliance field. Due to their simple structure, low cost, and ease of control, they have become the core driving components of traditional home appliances. Common applications include: washing machine pulsator drive, achieving clothes washing through forward and reverse rotation; refrigerator compressor auxiliary fan, maintaining stable internal temperature; vacuum cleaner motor, providing high-speed airflow; high torque power output for juicers and blenders; microwave oven turntable motor, achieving uniform heating; dishwasher pump motor driving water circulation, etc. BDC motors excel in low-speed, high-torque applications, making them ideal for devices that prioritize consistent power delivery over high rotational speeds. Although BDC motors exhibit slightly higher noise levels and shorter lifespans compared to Brushless DC (BLDC) motors, they remain highly competitive in cost-sensitive appliance applications, particularly dominating the mid-to-low-end market segment. As technology advances, certain high-end appliances are gradually transitioning to more efficient brushless motors. However, thanks to their mature technology and excellent cost-effectiveness, BDC motors are expected to remain a viable and active solution in the short term^[1].

This article mainly discusses the restart problem caused by accidentally entering TEST Mode during the use of BDC motor drivers, taking DRV8231 as an example. It first introduces the basic principles of BDC motor drivers, then elaborates in detail on the reasons for entering TEST mode, the behavior, and the methods to exit TEST mode. Furthermore, it proposes some improvement measures for the chip's anti-interference capability to avoid the chip erroneously entering TEST mode, aiming to provide reference for other designers of BDC drivers such as DRV8231.