JPS6240065A - Electric power unit - Google Patents

Abstract

PURPOSE:To shorten the rise time of a power output level by providing a means particularly suppling currents only on the rise time of the base currents of a switching transistor. CONSTITUTION:A rectangular wave signal is inputted to a remote control circuit 26 from an input terminal 25, and a switching transistor 6 connected in series with a primary winding 3 for a transformer 2 for boosting is ON-OFF controlled by the input of the signal. High voltage induced in a secondary winding 5 for the transformer 2 for boosting is lead out of output terminals 8, 9 through a capacitor 7 for resonance. A base current supply means 27 particularly supplies a base for the switching transistor 6 with currents only on the rise time of the base currents of the switching transistor 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a power supply device, and particularly to a power supply device with improved rise characteristics of its power output level.

[Prior art]

For example, high IIE power supply output can be quickly intermittent (on/off).
In conventional power supplies for electronic devices such as
Generally, the rise time from when an output ON signal is input until the output actually reaches a predetermined potential level is too long, which often becomes an obstacle to high-speed on/off operations.

FIG. 1 shows an example of a waveform diagram explaining this rising operation. Reference numeral 1 denotes a rectangular wave input signal for turning on and off the output, and the output is turned on at high level H (110) - output is turned on at level L. 0 is the power output,
This example shows a case where the output is a sinusoidal AC output. The rise time from when the low level L ON signal 1 is input until the actual output 0 reaches a predetermined potential level is t''.

Particularly in this mtm source device, which requires repeating the output on and off at high speed, it is natural that the rise time tr
[Purpose] The present invention has been made in view of the problems in the conventional examples as described above, and it improves the rise characteristics of the output level of this type of power supply device to achieve high-speed operation. The purpose is to provide a power supply circuit that can be switched on and off.

〔Example〕

The present invention will be explained below based on examples. 1 in Figure 2
1 is a diagram showing an embodiment of a high voltage source circuit configuration according to the present invention. 1
is a low-pass filter for smoothing ripples on the power line Vcc, 2 is a step-up transformer, 3 is its primary winding, 4 is a pace winding, 5 is a secondary winding, and 6 is a primary winding 3 7 is a resonant capacitor, and 8 and 9 are high voltage AC output terminals. The resistor 10 and capacitor 11 are
A charging/discharging time constant circuit for the current supplied to the base of the switching transistor 6 is formed.

Further, 38 indicates a circuit for supplying current to the base for starting oscillation. 26 is a remote control circuit for turning on/off the output of the L source by inputting a rectangular wave signal from the input terminal 25; 12 is a transistor that operates as a switch; 13 is a resistor; 17, -4mffjJ control resistor, 15 is a speed-up capacitor, and 24 is a pull-up resistor.

Further, 27 is base current supply means for the switching transistor 6, which is provided according to the principle of the present invention. 16
is a diode for regulating the direction of this current to a certain direction, and 17 and 18 are resistors for regulating the amount of current supplied to the base. Reference numeral 19 denotes a transistor that operates as a switch, and is configured to differentiate the rectangular wave signal from the input terminal 25 by a capacitor 22 when it is low repeat/I/L, and turn off the transistor 19 momentarily. 20
．． 21 and 23 indicate each resistance.

Next, the operation of the circuit of this embodiment will be explained. When a small amount of current II flows through the base of the switching transistor 60,
The flefter current Ic, which is a direct current amplification factor J@=Ic/In, flows to the collector, and first, (4) the collector-emitter potential vex decreases. →(B) Volume 1 of Trance 2! The potential across 30 decreases.

→(The potential across the secondary winding 4 increases at zero time.→(D)
The base current reduction factor 1 of the switching transistor 6 increases. →(4)~(D).

In the above-described loop, the positive feedback of (4) to (2) is generated, and the switching transistor 6 rapidly turns on. Figure 3 is a waveform diagram of each part representing this self-excited oscillation operation.
8 is a collector bottom pressure waveform of the switching transistor 6, 30 is a collector current rc waveform thereof, and 34 is an output voltage waveform between the output terminals 8 and 9. 32ri indicates the period of the rapid on state of the switching transistor 6.

On the other hand, as the pace current Im of the switching transistor 6 is supplied, the electric charge of the time constant capacitor 11 decreases and the potential decreases, and damping is applied to the positive feedback of (4) to (D) above, Current II decreases.→(G) Collector-emitter potential MCI increases.→(G)
The potential across the primary winding 3 of the transformer 2 decreases. →＠The potential between secondary winding 4 decreases 0→(smell~(season).

In the above-described loop, the switching transistor 6 rapidly turns off. FIG. 33 shows the duration of this state. Under the energy stored in the transformer 2 during the total period 31 of periods 32 and 33, it resonates due to the secondary inductance of the transistor 2, the stray capacitance, the D capacitance of the resonance capacitor 7, and the resistance of both. . In this way, an AC sine wave output as shown in FIG. 34 is produced between the output terminals a and '9. 29 indicates the output on/off interval.

FIG. 4 shows the base current supply circuit 2 of the switching transistor 6, which is a feature of the present invention, in FIG. 2 of the present embodiment.
7 is an input signal waveform diagram 35 and a pace potential waveform diagram showing the operation of the conventional circuit when no circuit is attached. 35 is
It represents the rectangular wave signal level of the input terminal 25 to the remote control circuit 26 in FIG. Due to the capacitance, the base potential gradually rises as shown in Figure 4, 36, and 3γ is the charging period, which results in a delay in the rise time of the predetermined voltage between the output terminals (tr in Figure 1). appear.

FIG. 5 shows the circuit 2 according to the invention as shown in FIG.
This is a diagram corresponding to FIG. 4 when 7 is added, and 41 indicates the collector potential waveform of the transistor 19. When the input rectangular wave signal 35 at the terminal 25 falls (low level L), the transistor 19 turns off for a short time, and current is supplied to the base of the transistor 6 through its 1fJj, the resistor 17, and the diode 16. 39 represents the period, and the collector potential waveform becomes as shown in 41.In this way, current is suddenly supplied to the switching transistor 60 pace only at the time of rising, and by causing the switching transistor 60 to rise rapidly, the base Ichihara's The rise time delay 11S1 is significantly reduced as shown in FIG.

Note that by adding the circuit 27 as described above, the second fA380 starting circuit may be omitted;
If the switching transistor 60 requires a certain level of base current, it may not be omitted.

Further, in this embodiment, the case of a self-excited oscillation circuit has been described, but the present invention can also be applied to the case of a separately-excited oscillation circuit.

Furthermore, in this embodiment, a high-voltage AC Mi source circuit has been described, but IK style? 4! It is also applicable in the case of source circuits.

〔effect〕

As explained above, according to the present invention, since a means for specifically supplying current to the base T of the switching transistor only at the rise of the current is provided, the rise time of the power supply output level can be significantly shortened. Ta.

[Brief explanation of drawings]

FIG. 1 is a waveform diagram of the rising operation of the output level of a conventional power supply circuit, FIG. 2 is a diagram of an embodiment of the high EEt source circuit according to the present invention, and FIG. 3 is a diagram showing the self-oscillation operation of the present embodiment. The waveform diagrams of each part, FIG. 4, and FIG. 5 are rise characteristic diagrams of the conventional example and this embodiment, respectively. 2......Step-up transformer 6...Switching transistor 8.9
...Output terminal 16...Diode 19...
......Transistor 27...
...Base current supply rotary path (means) 40...
・・・・・・Rise time tr・・・・・・・・・・・・
・Rise time Figure 3 Figure 4 Figure 5 71

Claims (1)

[Claims] A switching transistor that is connected to the primary winding side of the transformer and performs a switching operation by intermittent base current, is operated independently of the base current supply means only when the base current by the base current supply means rises. A power supply device characterized in that the transistor drive circuit is provided with means for supplying current to the base.