Alternating-current wide-voltage-input direct-current negative-voltage output power supply voltage-stabilizing chip

Abstract

The invention discloses an alternating-current wide-voltage-input direct-current negative-voltage output power supply voltage-stabilizing chip. By utilizing an external half-wave rectification diode,an alternating current is rectified into a same-phase pulse wave current; in each same-phase pulse wave, power supply work is carried out only in an extremely short time and a low-voltage area; alternating-current low-frequency synchronous oscillation power supply is carried out in the low-voltage area by utilizing alternating-current synchronous zero detection clamping in the chip; then dynamic charging is dynamically carried out on an external energy storage capacitor by utilizing low-frequency discontinuous pulses in the chip, so that constant voltage and current supply capacity is kept; and then the positive voltage is converted into a negative voltage to be output through a pump power supply. The chip can provide power supply of a household appliance control board and completely meetthe requirements for negative voltage driving of a high-power silicon controlled rectifier, can serve as a special voltage reduction driving chip for household appliances, and has the advantages of small size, no EMI / EMC interference, no heating and low cost.

Description

technical field [0001] The invention relates to a power supply stabilizing chip capable of inputting wide AC voltage and outputting DC negative voltage. Background technique [0002] In the field of home appliance control boards, TRIAC thyristors are indispensable driving components, especially in the case of high-power thyristor components, in order to drive the thyristors correctly, the thyristors must work in quadrants II and III , to ensure complete triggering of the thyristor with the minimum trigger current. [0003] When traditional circuit design converts AC power into DC power, the following methods are often used: [0004] a. Transformer step-down method: [0005] Advantages: high cost, no EMI / EMC problems, large output current. [0006] Disadvantages: heavy weight, large volume, low efficiency, and the heating of silicon steel sheet does not meet the EU ERP standard. [0007] b. Switching power supply step-down method: [0008] Advantages: small size, light w...

AI Technical Summary

Problems solved by technology

[0006] Disadvantages: heavy weight, large volume, low efficiency, silicon steel sheet heating does not meet the EU ERP standard

[0009] Disadvantages: There are EMI / EMC problems, moderate cost, many peripheral components, and high heat generation of MOS tubes

[0012] Disadvantages: low efficiency, small output current, serious heating of resistors, does not meet EU ERP standards

[0015] Disadvantages: large size, low efficiency, easy aging of capacitor life and affected by temperature, does not meet the EU ERP standard, and the current limiting resistor is easy to break down and burn.

[0016] Among the above-mentioned methods of converting AC power into DC power, the resistance-capacitance step-down method is the most commonly used method at present. Please refer to Figure 1, that is, the resistance-capacitance step-down method is used as the thyristor The circuit diagram of the power supply, the input end of the circuit includes an AC power supply, which is connected in series and parallel with a resistor and a capacitor, so that the maximum current of the AC power supply is limited by the capacitor and resistor, and two diodes are connected The rectification circuit formed rectifies the AC current into a DC current, and then outputs a regulated DC power supply through a Zener diode and an electrolytic capacitor as the current of the gate DC trigger signal of a plurality of thyristors. Due to the large size of the capacitor, it causes troubles in assembly, and the capacitor is easy to age, so it has a limited service life. As for the resistor, it may be broken down and burned

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