CN205212719U - Full current feedback system - Google Patents

Abstract

The utility model discloses a full current feedback system, including the switching power converter, the input input line voltage of primary side coil, first end connection of electric lines in the primary side coil of power switch, the second end of power switch passes through grounding, PWM signal generator's output electric connection in power switch driver, the power switch driver electric connection hold in on -off control, the current control end electric connection hold in the second of power switch, on -off control holds electric connection in the control end of power switch, current feedback input passes through feedback network and ancillary coil signal connection. The utility model provides a defect of ACDC power management chip circuit in the existing market, if the CS pin takes place the short circuit, after the clock falling edge, the former limit of transformer electric current will grow sustainedly to the transformer saturation, finally burns out the transformer primary coil so.

Description

A kind of total current reponse system

Technical field

The utility model belongs to power technique fields, is specifically related to a kind of total current reponse system.

Background technology

In contemporary electronic systems, AC-DC conversion is an indispensable important component part.All systems by AC-powered all need the direct voltage or the electric current that by an AC-DC converter, High Level AC Voltage are transformed into low pressure, and then provide power supply for chip control system.Traditional AC-DC converter (linear power supply) first directly becomes linevoltage (line voltage) into low-voltage AC by public frequency power transformer, be transformed into required low-voltage dc power supply by LDO (Low-dropoutregulator) again, and then be supplied to chip control system.This traditional AC-DC converting system due to energy consumption high, efficiency low just progressively replace by the switch power supply system that controls based on PWM mode.At present, the AC-DC converter system realized based on SMPS (Switching Power Supply) has become the main flow in market, and be applied in the electronic system of nearly all Alternating Current Power Supply, and the kernel control chip in this type systematic, AC-DC power management chip also obtained significant progress at nearly 20 years and popularizes widely.

Utility model content

The purpose of this utility model is to provide a kind of total current reponse system, to solve the problem proposed in above-mentioned background technology.

For achieving the above object, the utility model provides following technical scheme: a kind of total current reponse system, comprise switch power converter, current controling end, switch control terminal and feedback input end, pwm signal generator and power switch driver, described switch power converter comprises transformer and power switch, described transformer comprises primary side coil, secondary side coil and ancillary coil, the input input line voltage of described primary side coil, the first end of described power switch is electrically connected at primary side coil, second end of described power switch passes through grounding through resistance, the output of described pwm signal generator is electrically connected at power switch driver, described power switch driver is electrically connected at switch control terminal, described current controling end is electrically connected at the second end of power switch, described switch control terminal is electrically connected at the control end of power switch, described feedback input end is connected with auxiliary winding signal by feedback network.

Technique effect of the present utility model and advantage: this total current reponse system, compared with traditional reponse system, the utility model solves the defect of AC/DC power management chip circuit in the market, if CS pin is short-circuited, so after clock falling edge, primary side current of transformer will continue to increase to transformer saturated, finally burn primary transformer coil, simultaneously, the utility model possesses switch power controller and the lowest point changing method thereof, the lowest point moment can be found adaptively according to the change of load current, and make power switch conducting in the lowest point moment, solve power management chip in each switching process, the electric current of primary transformer coil all can flow through the loss that power switch brings energy, this energy loss increases along with the rising of switching frequency, except energy loss, the large electric current existed in each power switch handoff procedure and the rate of change of voltage also bring serious electromagnetic interference (EMI) problem, and this system possesses low cost 3 pin primary side feedback AC-DC Switching Power Supply (SMPS) controller chip, therefore the technical merit of this product reaches international most advanced level, in current feedback, stand-by power consumption, the technology such as audio-frequency noise and cost has higher leading superiority.

Accompanying drawing explanation

Fig. 1 is structural representation of the present utility model.

Embodiment

Below in conjunction with the accompanying drawing in the utility model embodiment, be clearly and completely described the technical scheme in the utility model embodiment, obviously, described embodiment is only the utility model part embodiment, instead of whole embodiments.Based on the embodiment in the utility model, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all belong to the scope of the utility model protection.

The utility model provides a kind of total current reponse system as shown in Figure 1, comprise switch power converter, current controling end, switch control terminal and feedback input end, pwm signal generator and power switch driver, described switch power converter comprises transformer and power switch, described transformer comprises primary side coil, secondary side coil and ancillary coil, the input input line voltage of described primary side coil, the first end of described power switch is electrically connected at primary side coil, second end of described power switch passes through grounding through resistance, the output of described pwm signal generator is electrically connected at power switch driver, described power switch driver is electrically connected at switch control terminal, described current controling end is electrically connected at the second end of power switch, described switch control terminal is electrically connected at the control end of power switch, described feedback input end is connected with auxiliary winding signal by feedback network.

Operation principle: during work, produces window signal while the pwm signal producing this pwm signal generator; The voltage of the current controling signal relatively inputted by this current controling end and threshold voltage, and export comparative voltage, wherein the voltage of this current controling signal increased gradually in this pwm signal conduction period; Triggered the detection of this comparative voltage by this window signal, determine whether triggering first reset signal according to this comparative voltage, this first reset signal is used for resetting to the pwm signal of current period; Trigger the second reset signal by the saltus step of this comparative voltage, this second reset signal is used for resetting to the pwm signal of current period; Wherein, when this pwm signal is reset, power switch driver closes this power switch.When this window signal detection trigger, when this comparative voltage is the first level, show the non-short circuit of this current controling end, do not trigger this first reset signal; When this comparative voltage is second electrical level, show this Current Control terminal shortcircuit, trigger this first reset signal, when wherein the moment of this window signal detection trigger is later than the non-short circuit of this current controling end, the voltage of this current controling signal reaches the moment of this threshold voltage.

This total current reponse system, compared with traditional reponse system, the utility model solves the defect of AC/DC power management chip circuit in the market, if CS pin is short-circuited, so after clock falling edge, primary side current of transformer will continue to increase to transformer saturated, finally burn primary transformer coil, simultaneously, the utility model possesses switch power controller and the lowest point changing method thereof, the lowest point moment can be found adaptively according to the change of load current, and make power switch conducting in the lowest point moment, solve power management chip in each switching process, the electric current of primary transformer coil all can flow through the loss that power switch brings energy, this energy loss increases along with the rising of switching frequency, except energy loss, the large electric current existed in each power switch handoff procedure and the rate of change of voltage also bring serious electromagnetic interference (EMI) problem, and this system possesses low cost 3 pin primary side feedback AC-DC Switching Power Supply (SMPS) controller chip, therefore the technical merit of this product reaches international most advanced level, in current feedback, stand-by power consumption, the technology such as audio-frequency noise and cost has higher leading superiority.

Last it is noted that the foregoing is only preferred embodiment of the present utility model; be not limited to the utility model; although be described in detail the utility model with reference to previous embodiment; for a person skilled in the art; it still can be modified to the technical scheme described in foregoing embodiments; or equivalent replacement is carried out to wherein portion of techniques feature; all within spirit of the present utility model and principle; any amendment of doing, equivalent replacement, improvement etc., all should be included within protection range of the present utility model.

Claims (1)

1. a total current reponse system, comprise switch power converter, current controling end, switch control terminal and feedback input end, pwm signal generator and power switch driver, it is characterized in that: described switch power converter comprises transformer and power switch, described transformer comprises primary side coil, secondary side coil and ancillary coil, the input input line voltage of described primary side coil, the first end of described power switch is electrically connected at primary side coil, second end of described power switch passes through grounding through resistance, the output of described pwm signal generator is electrically connected at power switch driver, described power switch driver is electrically connected at switch control terminal, described current controling end is electrically connected at the second end of power switch, described switch control terminal is electrically connected at the control end of power switch, described feedback input end is connected with auxiliary winding signal by feedback network.