Voltage fluctuation resistant delay switch circuit based on rising edge sampling

Abstract

The invention belongs to the technical field of electronics, and discloses a voltage fluctuation resistant delay switch circuit based on rising edge sampling, which comprises an input interface Vin +and an input interface Vin-, an output interface Vout +, an output interface Vout-, a resistor R1, a capacitor C1, a voltage stabilizing diode VD1, a resistor R2, an NPN triode Q1, a resistor R4, a capacitor C2, a resistor R5 and a P-MOS tube MQ1 and a voltage stabilizing diode VD2; the first end of R1 is connected with Vin +, and the second end of R1 is connected with Vin- through the C1, the negative electrode of the VD1 is connected with the second end of the R1, the positive electrode of the VD1 is connected with the base electrode of the Q1 through the R2, and the emitter electrode of theQ1 is connected with the Vin-, the first end of R4 is connected with the collector electrode of the Q1, and the second end of R4 is connected with Vin + through the C2; the first end of R5 is connected with the second end of R4, and the second end of R5 is connected with Vin +; the source electrode of MQ1 is connected with Vin +, the grid electrode of MQ1 is connected with the second end of R4, and the drain electrode of MQ1 is connected with Vout +; the positive electrode of the VD2 is connected with the second end of the R1, and the negative electrode of the VD2 is connected with the drainelectrode of the MQ1, and Vin- and Vout- are grounded.

Description

technical field [0001] The invention relates to the field of electronic technology, in particular to a voltage fluctuation-resistant delay switch circuit based on rising edge sampling. Background technique [0002] The widespread use of high-power equipment in the existing network will cause fluctuations in the mains power supply when it is powered on, causing other equipment in use to suddenly power off and then power on again. This sudden change in power supply may cause the equipment to start abnormally. In the circuit design, the chip has certain requirements on the power-on sequence and the power-off sequence. If the sequence requirements are not met, for example, in the case of fast switching on and off, unstable power supply, etc., the residual voltage cannot be released in time after power-off. Power-on again quickly, or the rising edge of power-on is discontinuous, etc., will cause the device to fail to start normally or some functions will be abnormal after startup...

AI Technical Summary

Problems solved by technology

[0002] The widespread use of high-power equipment in the existing network, when it is powered on, will cause fluctuations in the mains power supply, causing other equipment in use to suddenly power off and then power on again. This sudden change in power supply may cause the equipment to start abnormally

In the circuit design, the chip has certain requirements on the power-on sequence and the power-off sequence. If the sequence requirements are not met, for example, in the case of fast switching on and off, unstable power supply, etc., the residual voltage cannot be released in time after power-off. Power on quickly, or the rising edge of power on is not continuous, etc., will cause the device to fail to start normally or some functions will be abnormal after startup.

[0003] In this regard, the existing technology adopts the scheme of delaying the power on, and generally adopts the slow start circuit, but the delay is short and the adjustable range is narrow, only in milliseconds, so it is difficult to efficiently deal with the above problems

Or add a large capacitor at the output end of the power supply, but this will cause excessive current at the moment of power supply connection, trigger over-current protection, and fail to feed normally. Even if it can feed normally, the increase of the large capacitor will cause the power stored in the capacitor to leak slow down, causing the rising edge of power-on to become slow, affecting the next power-on sequence

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