CN2501243Y

CN2501243Y - DC-DC mini boosted circuit

Info

Publication number: CN2501243Y
Application number: CN 01255952
Authority: CN
Inventors: 符术林
Original assignee: LIANG ZUNQIANG
Current assignee: LIANG ZUNQIANG
Priority date: 2001-09-24
Filing date: 2001-09-24
Publication date: 2002-07-17
Anticipated expiration: 2011-09-24

Abstract

A DC-DC mini-boost circuit comprises a main working circuit (1), a drive circuit of high frequency oscillation and output thereof (2), a comparative circuit (3), a soft staring circuit (4) and a detecting circuit (5). The output end of the soft staring circuit (4) is connected with the input end of the drive circuit of high frequency oscillation and output thereof (2), the other output end of the soft staring circuit (4) is connected with the controlling end of the detecting circuit (5). The output end of the detecting circuit (5) is connected with the input end of the comparative circuit (3). The other input end of the comparative circuit (3) is connected with the controlling end of the reference voltage (6). The output end of the comparative circuit (3) is connected with the input end of the drive circuit of high frequency oscillation and output thereof (2). The volume of the circuit is small, and the output voltage of the circuit is stable.

Description

The miniature booster circuit of DC-DC

1, technical field:

The utility model relates to a kind of higher-order of oscillation voltage boosting and stabilizing circuit.

2, background technology:

At present, the DC-DC booster circuit all is to adopt independent switching tube oscillation boosting, and output voltage stability is good inadequately, is easy to be subjected to the influence of the variation of input voltage, and adopts discrete component, and required volumetric spaces is big.

3, summary of the invention:

The purpose of this utility model provides the miniature booster circuit of a kind of DC-DC, it all highly integrates the higher-order of oscillation, reference voltage comparison circuit, soft starting circuit etc., make the voltage of the output of boosting stable, the influence that not changed by input voltage, the entire product volume is little.

The utility model is achieved by the following technical solution: it comprises main operating circuit and the higher-order of oscillation and output driving circuit thereof, the output of the higher-order of oscillation and output driving circuit thereof is connected with the control end of main operating circuit, it also comprises comparison circuit in addition, soft starting circuit and testing circuit, the output of main operating circuit is connected with the input of testing circuit and soft starting circuit, an output of soft starting circuit is connected with the input of the higher-order of oscillation and output driving circuit thereof, another output of soft starting circuit is connected with the control end of testing circuit, the output of testing circuit is connected with the input of comparison circuit, another input of comparison circuit is connected with reference voltage, and the output of comparison circuit links to each other with the input of the higher-order of oscillation and output driving circuit thereof.

The above-mentioned described higher-order of oscillation and output driving circuit, comparison circuit, soft starting circuit, testing circuit and reference voltage are integrated into an IC chip.

The utility model compared with prior art has following advantage: because the utility model circuit carries out Highgrade integration to soft start, reference voltage comparison circuit, the higher-order of oscillation and output driving circuit thereof, be integrated into an IC, thereby its volume can be done very for a short time, owing to adopt the reference voltage comparison circuit, thereby its output voltage is not subjected to the influence of input voltage variation, output voltage stabilization.

4, description of drawings:

Below in conjunction with accompanying drawing the utility model is done detailed explanation:

Fig. 1 is a circuit block diagram of the present utility model;

Fig. 2 is the circuit diagram of Fig. 1 correspondence.

5, embodiment:

As Fig. 1, shown in Figure 2, the miniature booster circuit of DC-DC, comprise the main operating circuit (1) and the higher-order of oscillation and output driving circuit (2) thereof, the output of the higher-order of oscillation and output driving circuit thereof (2) is connected with the control end of main operating circuit (1), it also comprises comparison circuit (3) in addition, soft starting circuit (4) and testing circuit (5), the output of main operating circuit (1) is connected with the input of testing circuit (5) with soft starting circuit (4), an output of soft starting circuit (4) is connected with the input of the higher-order of oscillation and output driving circuit (2) thereof, another output of soft starting circuit (4) is connected with the control end of testing circuit (5), the output of testing circuit (5) is connected with the input of comparison circuit (3), another input of comparison circuit (3) is connected with reference voltage (6), and the output of comparison circuit (3) links to each other with the input of the higher-order of oscillation and output driving circuit (2) thereof.The higher-order of oscillation and output driving circuit thereof (2), comparison circuit (3), soft starting circuit (4), testing circuit (5) and reference voltage (6) are integrated into an IC chip in addition, make the entire product volume very little.

As shown in Figure 2, principle of the present utility model is: main operating circuit (1) comprises inductance L 1, diode D1, capacitor C 1; Testing circuit (5) mainly comprises resistance R 3, R4; Soft starting circuit (4) mainly comprises field effect transistor Q1, switching tube Q3, resistance R 3, R4.When input voltage Vi, provide oscillating voltage and oscillating condition by soft starting circuit (4), its working method is as follows, when input voltage Vi gives switching tube Q3 power supply through diode D1, simultaneously through resistance R 3, R4 provides bias current to cause the Q3 energising for switching tube Q3, switching tube Q3 conducting, grid voltage is provided for field effect transistor Q1, field effect transistor Q1 is conducting also, cause A point current potential to descend, be lower than reference data voltage, comparator output high level, operating voltage is provided for the higher-order of oscillation and output driving circuit (2) thereof, simultaneously, switching tube Q3 collector electrode output high level provides oscillating condition for oscillating circuit, thereby make the higher-order of oscillation and output driving circuit thereof start working, produce the square wave of 100KHZ, carry out the waveform adjustment through inverter, the Kai Heguan of control field effect transistor Q2, inductance L 1, capacitor C 1, diode D1 constitutes booster circuit together, when field effect pipe Q1 conducting, Vi is through inductance L 1, field effect transistor Q2 forms the loop to ground, and according to the characteristic of inductance, it will hinder the increase of electric current, produce induced voltage, produce the positive right negative electromotive force in a left side at inductance L 1 two ends, at this moment, inductance is in the storage power state, when field effect pipe Q2 ends, inductance L 1 produces the negative inverse electromotive force in a positive left side, the right side, and this voltage charges to capacitor C 1 through diode D1, when field effect pipe Q2 conducting, the time of the voltage discharge at cycle of oscillation and capacitor C 1 two ends, the voltage at C1 two ends will be in a stable state when being in balance.When the voltage on the capacitor C 1 is higher than 3V, promptly when the A point voltage is higher than reference voltage, comparison circuit (3) output low level, the higher-order of oscillation failure of oscillations causes output voltage to descend, and is that circuit recovers normal operating conditions again when voltage is reduced to 3V.

Claims

1, the miniature booster circuit of DC-DC, comprise the main operating circuit (1) and the higher-order of oscillation and output driving circuit (2) thereof, the output of the higher-order of oscillation and output driving circuit thereof (2) is connected with the control end of main operating circuit (1), it is characterized in that it also comprises comparison circuit (3), soft starting circuit (4) and testing circuit (5), the output of main operating circuit (1) is connected with the input of testing circuit (5) with soft starting circuit (4), an output of soft starting circuit (4) is connected with the input of the higher-order of oscillation and output driving circuit (2) thereof, another output of soft starting circuit (4) is connected with the control end of testing circuit (5), the output of testing circuit (5) is connected with the input of comparison circuit (3), another input of comparison circuit (3) is connected with reference voltage (6), and the output of comparison circuit (3) links to each other with the input of the higher-order of oscillation and output driving circuit (2) thereof.

2, the miniature booster circuit of DC-DC according to claim 1 is characterized in that the higher-order of oscillation and output driving circuit thereof (2), comparison circuit (3), soft starting circuit (4), testing circuit (5) and reference voltage (6) are integrated into an IC chip.