An anti-interference low-voltage detection circuit

Abstract

The invention belongs to the field of integrated circuits, and relates to an anti-interference low-voltage detection circuit comprising a reference voltage circuit, a resistor voltage division circuit, a logical combination circuit, a shaping circuit, a recovery voltage setting circuit and a capacitance charge and discharge circuit. A resistor R1, a resistor R2, a resistor R3, and a resistor R4 of the resistor voltage division circuit are sequentially connected end to end. An initiating end R1 is connected to an input voltage VIN. The tail end R4 is grounded. The resistance value of R1 is equal to the resistance value of R4. An anode of a comparator in the logic combination circuit is connected with the reference voltage circuit. A voltage of a cathode is generated through voltage division by the resistor voltage division circuit. An output of an inverter 1 in the logical combination circuit is used for controlling charge and discharge of a capacitor. After the voltages generated by the two ends of the capacitor go through the shaping circuit, control signals are output, and at the same time, an output of a Schmidt shaping circuit of the shaping circuit is used for controlling the switching-on of an M1 and an M2 in order to set a recovery voltage. The anti-interference low-voltage detection circuit of the invention is advantageous in that: the anti-interference low-voltage detection circuit is strong in anti-interference capabilities, high in precision and accuracy, and easy to change.

Description

[0001] technical field [0002] The invention belongs to the field of integrated circuits, and in particular relates to an anti-interference low-voltage detection circuit. Background technique [0003] As is well known, a voltage detection circuit detects a supply voltage, and when the voltage changes to a certain set value, the voltage detection circuit outputs a control signal. When we set this standard voltage value, we hope that the circuit can accurately detect and output the corresponding control signal. It is easy to do this in the voltage detection circuit of the prior art, but there are also disadvantages such as weak anti-interference ability, low accuracy, unfavorable modification, unstable output signal and the like. [0004] See figure 1 As shown, this is an electrical schematic diagram of a voltage detection circuit in the prior art. The voltage detection circuit is composed of a resistance voltage divider circuit, a logic combination circuit, a recovery vol...

AI Technical Summary

Problems solved by technology

[0007] 1. Due to the existence of external interference signals, the detection results are not accurate enough

[0008] 2. The ratio of the recovery voltage to the original turn-on voltage is related to R1, R2, and R3, which is inconvenient and not accurate enough to change

[0009] 3. This circuit detects the instantaneous value of the input voltage, resulting in unstable output signal

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