Voltage detecting circuit, battery power prompting system and voltage detecting method

Abstract

The invention provides a voltage detecting circuit, a battery power prompting system and a voltage detecting method. The voltage detecting circuit based on a digital circuit comprises a digital circuit, a conversion circuit and a comparison circuit. The digital circuit has a first output end, an input end and a second output end. The first output end outputs a digital signal. The input end of theconversion circuit is coupled to the first output end of the digital circuit. The first input end of the comparison circuit receives a voltage signal representative of the to-be-detected voltage. Thesecond input end of the comparison circuit is coupled to the output end of the conversion circuit. The output end of the comparison circuit is coupled to the input end of the digital circuit. The digital circuit obtains a to-be-detected voltage level based on the output signal of the comparison circuit, and provides a control signal at the second output end of the digital circuit, wherein the control signal is generated based on the to-be-detected voltage level. According to the voltage detecting circuit, the battery power prompting system and the voltage detecting method in the embodiment, the detection can be realized only by occupying two pins of the digital circuit, so that extension of other functions of the digital circuit is facilitated; meanwhile, the complexity, the volume and thecost of the system are reduced, so that the system integration is facilitated, thereby improving the reliability of a portable electric tool in a relatively poor working environment.

Description

technical field [0001] The invention relates to an electronic circuit, in particular to a voltage detection circuit, a battery power prompt system and a voltage detection method. Background technique [0002] For electric tools, because there may be no mains power supply in some workplaces, or the use of power cords may cause inconvenience to work, so portable electric tools with built-in batteries have greater advantages. However, a sudden lack of battery power can cause problems for work. Therefore, an indication of the battery power level is also crucial to facilitate timely charging and prevent sudden power failure. [0003] In the circuit control of a portable electric tool, in order to reduce the research and development cost and facilitate the expansion of control functions, a digital chip is used. figure 1 A digital chip-based battery power detection scheme in a comparative technology is shown. In this scheme, the digital circuit outputs multiple digital signals i...

AI Technical Summary

Problems solved by technology

When the detection accuracy requirements increase, the pins of the digital chip can no longer even meet the requirements

Moreover, occupying too many pins also hinders the expansion of other functions of the digital chip.

In addition, this solution additionally uses multiple A / D converters and multiple comparators, which greatly increases the size and cost of the system

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