CN105898938A - Driving circuit of ballast type LED lamp - Google Patents

Abstract

The invention relates to a driving circuit of a ballast type LED lamp, and discloses a Schmitt trigger circuit which is capable of eliminating interference signals. The driving circuit is characterized in that a first resistor R1 is connected between a pin 6 and a point A of an integrated circuit IC, a first capacitor C1 is connected between the pin 6 and a point N, a second resistor R2 is connected between a pin 2 of the integrated circuit IC and the point A, and a third resistor R3 and a second capacitor C2 are connected between the pin 2 of the integrated circuit IC and the point N. The advantages lie in that voltage of the pin 6 and the pin 2 of the integrated circuit IC is not greatly changed due to interference signals after adopting the technical scheme disclosed by the invention, and thus the stability of a Schmitt trigger in operation is greatly improved.

Description

A kind of drive circuit of ballast formula LED

Technical field

The present invention relates to the driving power supply of a kind of solid luminous lamp, more particularly, it relates to a kind of ballast formula LED The drive circuit of lamp.

Background technology

LED semiconductor lighting is that State Council accelerates to cultivate and the new industry of development strategy.In the recent period, the Department of Science and Technology Work out " semiconductor lighting development in science and technology " 12 " ad hoc planning ", in the key task of ad hoc planning In application technical research, it is proposed that exploitation is efficient, low cost, highly reliable LED drive power.This explanation The LED drive power importance in technology of semiconductor illumination application field.

Owing to the life-span of LED is depended on driving power supply, the lamp failure of more than 99% is all owing to driving power supply to draw Rising, the life-span of LED is up to 50 more than 000h, but the matched life-span driving power supply is typically only About 10 000h. so can LED illuminator one of the key link of application be that it drives electricity Source problem.The problem existed for prior art, Chinese patent notification number CN 202931605U, China are specially Profit notification number CN 203340369U, Chinese patent notification number CN 203340329U, Chinese patent notification number CN 203675406U etc., it is proposed that the brand new technical scheme driving power supply of ballast formula LED, this driving Power supply compared with the existing technology has the distinguishing features such as high efficiency, highly reliable, long-life and low cost.Greatly The application aspect of the LED of power, owing to the temperature characterisitic of the lamp C-V characteristic of LED is generally-4mV/ DEG C, even if the temperature characterisitic of this C-V characteristic shows to drive LED with constant-current source, big in temperature In the case of range (region is different, season is different, lamp is starting the variations in temperature to stable man-hour), The power that can make lamp changes, and this is the indeterminable technical problem of driving of existing LED.And root According to the inherent character driving power supply of ballast formula LED, this technical problem just can be efficiently solved, Modulating voltage temperature influence and when changing, the power supply that drives of ballast formula LED can make the power of LED keep Stable.Showing by the fact that above-mentioned, what LED needed is not constant-current source, is not constant pressure source, but can be full The ballast formula that foot LED requires drives power supply.Accordingly, the driving power supply of ballast formula LED will be future The direction of development.At Chinese patent notification number CN 202931605U, Chinese patent notification number CN Driving of the ballast formula LED that 203340369U, Chinese patent notification number CN 203340329U etc. are announced In the technical scheme in galvanic electricity source, become on a large scale at input voltage to improve the driving power supply of ballast formula LED Service behaviour during change, employs the IC chip of Schmidt trigger, and the input at power supply is arranged Sample circuit, obtains the amount of input voltage change.Owing to power supply includes interference signal, existing circuit Structure can not eliminate these interference signals effectively, makes Schmidt trigger misoperation under special circumstances, directly Connect and affect properties of product.

Summary of the invention

The drawbacks described above existed in view of prior art, the present invention provides a kind of Schmidt that can eliminate interference signal to touch Send out device circuit.

In order to achieve the above object, the present invention takes following technical scheme: driving of a kind of ballast formula LED Galvanic electricity road, including IC, it is characterised in that: at 6 feet and the A point of described IC Between be connected to the first resistance (R1), be connected to the first electric capacity (C1) between 6 feet and the N of described IC.

It is connected to the second resistance (R2), described integrated electricity between 2 feet and A point of described IC The 3rd resistance (R3) and the second electric capacity (C2) it is connected between 2 feet and the N of road IC.

It is an advantage of the current invention that to use after technical scheme, 6 feet of IC and 2 feet Voltage will not produce big change because of interference signal, thus when substantially increasing Schmidt trigger work Stability.

Accompanying drawing explanation

Fig. 1 is the local circuit structure principle chart driving power supply of existing ballast formula LED.

Fig. 2 is the local of the drive circuit of the existing ballast formula LED with short-circuit protection and open-circuit-protection Circuit structure schematic diagram.

Fig. 3 is the circuit structure schematic diagram of the present invention.

Detailed description of the invention

Shown in Fig. 1 is the local circuit structure principle chart driving power supply of existing ballast formula LED, figure Middle Schmitt trigger circuit is Chinese patent notification number CN 202931605U, Chinese patent notification number CN 203340369U, Chinese patent notification number CN 203340329U etc. are for improving driving of ballast formula LED The Schmitt trigger circuit that the galvanic electricity source service behaviour when input voltage wide variation is used.

Shown in Fig. 2 is the drive circuit of the existing ballast formula LED with short-circuit protection and open-circuit-protection Local circuit structure principle chart, be made up of IC and peripheral circuit in figure is Schmidt trigger, wherein IC Peripheral circuit to there to be technology (Fig. 1) to have 2 improvement.1 be filter capacitor change into low-voltage filtering, 2 It is to have added protection Zener diode.

Shown in Fig. 3 is the circuit structure schematic diagram of the present invention, in figure 6 feet of IC and A point it Between be connected to the first resistance R1, be connected to the first electric capacity C1 between 6 feet and the N of IC.Integrated circuit It is connected to the second resistance R2 between 2 feet of IC and A point, between 2 feet and the N of IC, is connected to the 3rd Resistance R3 and the second electric capacity C2.The A point of the sample circuit that the input of power supply is arranged be ripple be a tentering The pulsating dc voltage of value.When disturbing signal to be added between L and N of power supply, interference signal voltage is through taking Sample circuit dividing potential drop forms the interference signal voltage of certain amplitude at A point, and this voltage likely exceedes Schmidt and touches Send out the threshold voltage of device.Between 6 feet and A point of IC, it is connected to the first resistance R1 can decay Interference signal voltage, at 6 feet of IC and the indirectly first electric capacity C1 of N and the first resistance R1 The voltage that can make IC 6 foot together remains unchanged during disturbing pulse substantially.Its operation principle is When disturbing signal voltage to make A point voltage raise, the high voltage of A point passes through the first resistance R1 to the first electric capacity C1 charges, and meanwhile, another branch road high-tension of A point is to be discharged by R2, R3.Due to resistance R1 Much larger than R2, R3, the disturbing pulse voltage of A point is quickly bled off by R2, R3.Owing to resistance R1 is very big, The high voltage of A point passes through the first resistance R1 to the first electric capacity C1 charging current relative to R2, R3 discharge paths For the least.During disturbing pulse, voltage (the namely electricity of IC 6 foot of the first electric capacity C1 Pressure) substantially remain unchanged.As can be seen here, use technical scheme, Schmidt can be greatly improved and touch Send out stability during device work.

The resistance value changing R2, R3 can change the trigger voltage value of IC.Second electric capacity C2 is Reduce the ripple of 2 foot voltages of IC further, stablizing when being beneficial to Schmidt trigger work Property.Resistance R1 preferred 510K～750K ohm in Fig. 3, resistance R2 preferred 100K～110K ohm, Resistance R3 preferred 120K～130K ohm.C1 in Fig. 3 preferably 0.047～0.1uF, C2 preferably 0.047～ 0.1uF。

Claims (1)

1. a drive circuit for ballast formula LED, including IC, it is characterised in that: described IC 6 feet and A point between be connected to the first resistance (R1), the 6 of described IC The first electric capacity (C1) it is connected between foot and N；

It is connected to the second resistance (R2), described integrated electricity between 2 feet and A point of described IC The 3rd resistance (R3) and the second electric capacity (C2) it is connected between 2 feet and the N of road IC.