Programmable voltage monitoring circuit

Abstract

The invention discloses a programmable voltage monitoring circuit, which includes a programming control circuit, a monitoring voltage generation circuit and a real-time voltage monitoring circuit. The programming control circuit includes a programming state selection terminal and a state judgment circuit. The programming state selection terminal is used for The user can choose one of the four programming states of input grounding, power supply, floating and floating connection. The state judgment circuit generates a corresponding control signal according to the programming state selected by the user and outputs it to the monitoring voltage generating circuit; the monitoring voltage generating circuit The corresponding monitoring voltage is generated according to the input control signal and output to the real-time voltage monitoring circuit; the real-time voltage monitoring circuit compares the monitoring voltage with the voltage to be monitored, and generates corresponding monitoring results. The present invention increases the programming state and expands the scope of the voltage that the monitoring circuit can cover without adding programming pins and changing the programming mode.

Description

technical field [0001] The invention relates to voltage monitoring, in particular to a programmable voltage monitoring circuit. Background technique [0002] In the general application of programmable voltage monitoring circuit at present, each programming pin has three states: connected to power supply, grounded and floating; each pin generates two switch control signals, which are used to control the input resistance of a non-inverting amplifier, the non-inverting Amplifiers have different amplification factors when the input resistance is different, so as to generate different monitoring voltages. This programmable voltage monitoring circuit has 3N different voltage setting states, where N represents the number of programming pins. [0003] In the application of programmable voltage monitoring circuit, the following points should be paid attention to: [0004] 1) It is required that the values ​​of two adjacent monitoring voltages cannot be too far apart, otherwise the ...

AI Technical Summary

Problems solved by technology

[0009] First, when the programming accuracy is 0.1v (meaning that the difference between two adjacent monitoring voltages is 0.1v), and three programming pins are used, since the three pins can only have 3 N = 27 states, the variable range of programming is only 2.7v, which cannot cover the entire range from 1.8v to 5v. In order to expand the voltage coverage, it is necessary to increase the programming pins, which will cause loss of PCB area

[0010] Secondly, the circuit uses a non-inverting amplifier in the form of a resistor. When amplifying, the resistance of the amplifier forms a DC path to the ground potential, which will generate a large DC power consumption.

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