Switch power supply under-voltage protecting circuit for preventing starting by mistake and under-voltage protecting method

A switching power supply and under-voltage protection technology, which is applied in the direction of emergency protection circuit devices and electrical components, can solve the problems of power supply secondary start-up, under-voltage protection failure, etc., achieve accurate under-voltage protection function, avoid false start problems, and improve efficiency high effect

Inactive Publication Date: 2008-09-24
ASTEC POWER SUPPLY (SHENZHEN) CO LTD
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

like image 3 As shown, in the process of input voltage drop, similar to the process of input voltage rise, the circuit will fail the undervoltage protection after the VREF of the undervoltage protection disappears, and the power supply will start again

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Switch power supply under-voltage protecting circuit for preventing starting by mistake and under-voltage protecting method
  • Switch power supply under-voltage protecting circuit for preventing starting by mistake and under-voltage protecting method
  • Switch power supply under-voltage protecting circuit for preventing starting by mistake and under-voltage protecting method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0018] The present invention will be further described below in conjunction with the accompanying drawings.

[0019] The switching power supply undervoltage protection circuit such as Figure 4 As shown, it includes: comparator, voltage divider resistor network, reference voltage circuit and PWM master controller. The reference voltage circuit is independent of the PWM main controller. The reference voltage circuit is composed of a resistor and a voltage stabilizing device in series, and its minimum working voltage is lower than that of the main controller.

[0020] Figure 4 In the example, the comparator adopts operational amplifier A, R5 is its feedback resistor, and the reference voltage of its non-inverting input terminal is provided by the above-mentioned reference voltage circuit. The reference voltage circuit is composed of a resistor R1 and a voltage stabilizing device in series, and the common terminal of the two is connected to the non-inverting input terminal of ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

A switch power supply low-voltage protection circuit capable of preventing false-starting comprising a comparison device, a voltage splitting resistance network, a reference voltage circuit and a PWM master-control unit, wherein the comparison device exports to the operation status control input end of the master-control unit, the output signal of the master-control unit is used for the control of each switching element of the switch power supply, the reference voltage circuit is independent from the master-control unit and is composed by a resistance and a stabilizing device in series connection, whose minimum operating voltage is lower to the operating voltage of the master-controller. The comparison device in-phase terminal voltage is higher than the reversed phase terminal voltage during the whole booting and shutdown process, thus a high level is exported, making the PWM to be on the switch off status and preventing the false starting of the device.

Description

technical field [0001] The invention relates to a switching power supply undervoltage protection technology, in particular to a switching power supply undervoltage protection circuit capable of preventing false start and a switching power supply undervoltage protection method based on the circuit. Background technique [0002] In the switching power supply, the purpose of undervoltage protection is: (1) To prevent the main controller PWM duty cycle from being too large when the input voltage is lower than the designed minimum input voltage, the magnetic core reset time must be far from enough, resulting in magnetic saturation and damage Power device; (2) Prevent the PWM from starting when the input voltage is lower than the designed minimum input voltage, and the output voltage has a pre-start pulse, which affects the timing of the load circuit. Therefore, under any input voltage waveform, the PWM must have no output when the input voltage is lower than the designed minimum ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): H02H7/122
Inventor 李卫东王庆军
Owner ASTEC POWER SUPPLY (SHENZHEN) CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap