CN85108106A - Transistor inverter device - Google Patents

Abstract

A kind of transistor inverter device that can be used for fluorescent lamp can link to each other with fluorescent lamp, it is characterized in that using oscillator and switching circuit that comprises two parallel connected transistors of a generation square wave of being made by integrated circuit; Respond the square wave that above-mentioned oscillator takes place, in the half period of a square wave, a transistor turns, another disconnects, and in the lower half, then first transistor disconnects second conducting; One end of fluorescent lamp links to each other with the contact of two parallel connected transistors, and the other end links to each other with charging capacitor.

Description

Transistor inverter device

The present invention system be used for fluorescent lamp and other transistor inverter device is relevant.

Transistor converter is always formed by the transistor that oscillation transformer is connected with two " recommending " formulas, carries out alternating current-direct current (DC/AC) conversion therefrom.Promptly constitute the auto-excitation type oscillator.Because such alternating voltage that oscillator produced, be from the secondary coil of oscillation transformer, to take out, and supply load, so it is very big to cause in the oscillation transformer power consumption, power is extremely low.

Therefore, the objective of the invention is to: the AC/DC convertor in the auto-excitation type oscillator,, provides electric power to load, thereby obtains the transistor converter of low power consumption with two transistorized alternate conduction being connected in parallel with end for it with the separated exciting oscillator.

Below, with reference to accompanying drawing, the present invention is described.

Power supply S provides the power supply of 100 volts or 200 volts.In addition, fuse FS, capacitor C ₁, inductance L ₁And L ₂, capacitor C ₂And C ₃The noise reduction filter that constitutes continues with power supply S.By four diode D ₁, D ₂, D ₃And D ₄The bridge rectifier that constitutes links to each other with an end of noise reduction filter; The other end of noise reduction filter is by a resistance R ₁, link to each other with a commutator SW, thereby A and two contacts of B arranged.Contact B links to each other with the another bridge terminal of aforesaid bridge rectifier; Contact A and the capacitor C that constitutes level and smooth electric lattice device ₄And C ₅Mid point link.When the power supply that uses when exchanging 200 volts, switch SW places a B side.At this moment, carry out full-wave rectification, B by bridge rectifier ₀Point can obtain 280 volts of voltages of direct current.In addition, in this case, capacitor C ₄And C ₅Constitute smoothing circuit.On the other hand, when the power supply that uses when exchanging 100 volts, switch SW places contact A side, capacitor C ₄And C ₅, and diode D ₂And D ₄Constitute the voltage-multiplying type rectification circuit, so B ₀Point still can obtain 280 volts of commutating voltages.

280 volts of direct voltages that obtained, except being used to provide fluorescent lamp electric power, simultaneously, through dropping resistor R ₂With the voltage-stabiliser tube ZD of the usefulness of burning voltage, produce the IC(integrated circuit) with 12 volts of power supplys.Here, capacitor C ₆Be level and smooth usefulness.

Below, the oscillator used to the present invention explains.

Oscillator is by two NAND gate IC of C-MOS integrated circuit ₁And IC ₂, resistance R ₃, R ₄With capacitor C ₇Form.Here, resistance R ₃Be used to make working stability, resistance R ₄With capacitor R ₇The decision time constant.Change their numerical value, can obtain suitable frequency.In the present invention, select 12 kilo hertzs of frequencies to 20 kilohertz range the most suitable.Like this, in the present invention, just obtained 12 kilo hertzs of square waves to 20 khz frequencies that the C-MOS device provides for main oscillator, this frequency is through constituting not gate, the NAND gate IC that is continued by the parallel connection of C-MOS integrated circuit ₃And IC ₄, resistance R ₀, capacitor C ₈, provide frequency signal with the switch circuit to fluorescent lamp drive described later.In addition, resistance R ₅, diode D ₇, resistance R s, capacitor Cs establish for waveform shaping.In addition, the resistance R here ₀With capacitor C ₈, be used for simultaneously, also can making transistor Q described later outside the usefulness of the influence minimizing between the same vibration of transformer input ₁And Q ₂Switching carry out sleekly.

That is, owing to be provided with resistance R ₀With capacitor C ₈, rapid upper punch takes place in the forward position of the square wave that oscillator produces; The back produces opposite following dashing along same, makes transistor Q like this ₁And Q ₂Switching can carry out smoothly.

Then, switch circuit of the present invention is described.

In input transformer T, two-wire wound in parallel formula is around N ₁And N ₂Two reference coils are in addition also around the input transformer magnetic saturation coil about a circle or two circles.So, reference coil N ₁And N ₂Polarity is opposite, so presenting the voltage of opposite sign but equal magnitude in the reference coil.

Reference coil N ₁An end, the capacitor C that continues by parallel connection ₉And resistance R ₇, with transistor Q ₁Base stage join; The other end and transistor Q ₁Collector electrode join.Simultaneously, transistor Q ₁Collector electrode.Between the emitter, joining transistor Q ₁Protecting diode D ₅Transistor Q ₁Continuing with two transistors with the multiple tube form forms, and General Result is satisfactory, but is not limited to so certain.Transistor Q ₁Collector electrode and 280 volts of voltages of aforesaid direct current continue.

Because multiple tube is effective, so Q ₂Also be multiple tube, same, with capacitor C ₁₀, resistance R ₀, R ₁₀, diode D ₆Connect.

Like this, transistor Q ₁Emitter and transistor Q ₂Collector electrode link to each other transistor Q ₂Grounded emitter.

Here, aforesaid capacitor C ₉, resistance R ₇, R ₈Combination and capacitor C ₁₀, resistance R ₀, R ₁₀Combination, be respectively applied for transistor Q ₁, Q ₂The usefulness of base stage input waveform shaping.

As previously mentioned, according to the structure of switch circuit, reference coil N ₁In when presenting positive voltage, transistor Q ₁Conducting; Simultaneously, reference coil N ₂Present negative voltage this moment, so transistor Q ₂Turn-off.This state is as the same conversely.

His end of aforesaid reference coil is by coil N ₃And choke CH ₁, specifically be connected to the A end with fluorescent tube L() link to each other.Between the B of fluorescent tube L and the C end, follow capacitor C ₁₁, D is terminated at two capacitor C that connect and continue between 280 volts of DC power supply and the ground ₁₂With C ₁₃Mid point.Capacitor C ₁₂And C ₁₃, respectively with resistance R ₁₁And R ₁₂Parallel connection continues.These resistance shield to capacitor.

Below, the action of fluorescent-lamp-use transistor of the present invention conversion is described.

Power supply one is connected B ₀Point obtains 280 volts of direct currents.Meanwhile, oscillator sends square wave by NAND gate IC ₃And IC ₄, resistance R ₆, capacitor C ₈, supply with the switch circuit.This moment, during the positive half cycle of square wave, reference coil N ₁In present positive voltage, transistor Q ₁Conducting; Simultaneously, reference coil N ₂In present negative voltage, transistor Q ₂Turn-off.Therefore, the electric current of 280 volts of power supplys of direct current is from transistor Q ₁Collector electrode begin, flow through emitter, and then through coil N ₃, choke CH ₁, supply with fluorescent tube L.This electric current flows through fluorescent tube L, to capacitor C ₁₂And C ₁₈Mid point in flow into.Like this, as shown in the figure, capacitor C ₁₁, C ₁₂, and C ₁₃On all be full of.

Then, the negative half period of square wave, that is, and reference coil N ₂In present positive voltage, reference coil N ₁In when presenting negative voltage, transistor Q ₂Conducting, Q ₁Turn-off.Therefore, capacitor C ₁₁, C ₁₂, C ₁₃In the electric charge saved and preserve by choke CH ₁, coil N ₃, transistor Q ₂Discharge.

As mentioned above, in the phase weekly of square wave, transistor Q ₁And Q ₂Conducting and shutoff repeatedly in turn.

Like this, in the present invention, without self-excited oscillator, and with the few C-MOS oscillator of power consumption, make switch circuit "on" and "off" constantly, thereby make whole power consumption greatly reduce than original converter.

Accompanying drawing is a fluorescent-lamp-use transistor inverter device circuit diagram of the present invention, wherein:

S-power supply, D ₁, D ₂, D ₃, D ₄The diode of-bridge rectifier, ZD-voltage stabilizing didoe, IC ₁, IC ₂, IC ₃, IC ₄-C-MOS device, T-input transformer, N ₁, N ₂-reference coil, N ₃-saturation coil, Q ₁, Q ₂-transistor, L-fluorescent tube.

Claims (2)

1, a kind of transistor Bian Change apparatus that can be used for fluorescent lamp can link to each other with fluorescent lamp, it is characterized in that using oscillator and switching circuit that comprises two parallel connected transistors of a generation square wave of being made by integrated circuit; Respond the square wave that above-mentioned oscillator takes place, in the half period of a square wave, a transistor turns, another disconnects, and in the lower half, then first transistor disconnects second conducting; One end of fluorescent lamp links to each other with the contact of two parallel connected transistors, and the other end links to each other with charging capacitor.

2, transistor inverter device according to claim 1 is in series with resistance and electric capacity between described square-wave oscillator and described switching circuit, to guarantee the switching circuit operate as normal.