CN213693473U

CN213693473U - Voltage-stabilized power supply with soft start and ultralow turn-off current

Info

Publication number: CN213693473U
Application number: CN202021015402.6U
Authority: CN
Inventors: 王道金
Original assignee: Jiaxing Xingan Internet Of Vehicles Information Technology Co ltd
Current assignee: Jiaxing Xingan Internet Of Vehicles Information Technology Co ltd
Priority date: 2020-06-05
Filing date: 2020-06-05
Publication date: 2021-07-13
Anticipated expiration: 2030-06-05

Abstract

The utility model discloses a constant voltage power supply with soft start and ultralow turn-OFF current, including input Vin, output Vout and switch circuit, switch circuit respectively with input Vin with output Vout electric connection, switch circuit includes resistance R4, triode Q2, resistance R3 and triode Q3, resistance R4's a termination CTL _ ON/OFF and resistance R4's the other end with triode Q2's base electric connection. The utility model discloses a constant voltage power supply with soft start and ultralow turn-off current, its circuit structure is simple, and is with low costs to make whole circuit system current consumption fall to below 33nA when can close load power according to whole car consumption demand, the circuit still has start soft start protect function, level and smooth output simultaneously.

Description

Voltage-stabilized power supply with soft start and ultralow turn-off current

Technical Field

The utility model belongs to the technical field of constant voltage power supply, concretely relates to constant voltage power supply with soft start and ultralow turn-off current.

Background

An external camera is usually required in an automatic driving monitoring system or backing image assistance of a commercial automobile, the types of the cameras are digital two-way communication or CVBS analog output based on FPD-LinkIII and GMSL, and the system is required to supply power to the external camera no matter which camera is used. The automobile has strict quiescent current control requirements on each electronic component system to prevent the battery of the automobile from being short of power during the stop period, and the current is usually controlled within 1 milliampere or 100 microamperes, which has extremely high requirements on the whole 24V power supply commercial automobile. The following two power supply modes are mostly adopted in the current power supply system on the market:

1. the wide power LDO power supply mode shown in the attached figure 2 of the specification:

the wide power LDO with the enabling and turning-off control functions can achieve about 15uA at present, and when the required quantity is large, the total current is not small, especially under the requirement of 100 uA.

2. The general triode voltage-stabilized power supply is supplied by combining a switching circuit and a general triode voltage-stabilized power supply as shown in figures 3A and 3B of the attached drawings of the specification:

FIG. 3A is a fixed voltage regulator circuit. The resistor is used for providing bias current for the triode to conduct the triode and providing working current for the voltage stabilizing tube, and the voltage stabilizing tube is connected to the base. The voltage of the base electrode is stabilized by the voltage regulator tube, and the voltage of two ends is stable 0.7V (calculated by silicon tube) when the diode is conducted because the diode is arranged between the base electrode and the emitter electrode of the triode, so that the output voltage of the circuit is equal to the stabilized value of the voltage regulator tube minus 0.7V. The function of the capacitor is irrelevant to voltage stabilization, but the capacitor is often used in the voltage stabilizing circuit in a 'passing way', the function of the capacitor is to form an 'electronic filtering' circuit with the triode, and the filtering effect of expanding hFE (triode amplification factor) times is obtained at the output end by utilizing the amplification function of the triode, which is incomparable to the filtering capacitor connected at the output end;

FIG. 3B is a diagram of an output adjustable series regulated voltage regulator circuit. The triode V1 is a regulating tube and plays a role in regulating output voltage, and the V2 is a comparison amplifying tube and plays a role in controlling the regulating tube after comparing and amplifying a sampling signal and reference voltage. Resistor 1 is operative to provide bias current to transistor V1 to turn the transistor on, and resistor 1 is further operative to provide power to V2. The resistor 2 supplies working current to the voltage regulator tube, and the resistors 3, 4 and W form a sampling circuit. The voltage regulator tube provides a reference voltage for the V2, and the working principle of the circuit is as follows: if the output voltage is increased due to load variation, input voltage fluctuation or other reasons, after the sampling circuit samples the V2 base voltage, the V2 base current is increased, and after the V2 collector current is increased, the V2 collector voltage, i.e., the V1 base voltage, is decreased, the V1 emitter, i.e., the output voltage, is decreased, and as a result, the output voltage is not actually increased. Similarly, the output voltage will not drop, and only a stable value is obtained, and the output voltage can be adjusted to be high or low by adjusting W. The LDO with relatively wide cost and voltage is low, the LDO can stabilize the voltage, but the external load camera cannot be turned off along with the dormancy of the whole vehicle system, the power consumption is reduced, the cost is increased when the switching circuit is connected in series outside, and meanwhile, the base current of a lower control tube in the switching circuit is large, so that the power consumption of the load is not controlled.

Therefore, the above problems are further improved.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a main aim at provides a constant voltage power supply with soft start and ultralow turn-off current, its circuit structure is simple, and is with low costs to make whole circuit system current consumption fall to 33nA below when can close load power according to whole car consumption demand, the circuit still has start soft start protect function, smooth output simultaneously.

To achieve the above object, the present invention provides a regulated power supply with soft start and ultra-low turn-off current, including an input terminal Vin, an output terminal Vout and a switch circuit, the switch circuit respectively with the input terminal Vin with the output terminal Vout electric connection, wherein:

the switch circuit comprises a resistor R4, a triode Q2, a resistor R3 and a triode Q3, wherein one end of the resistor R4 is connected with an external connection end CTL _ ON/OFF, the other end of the resistor R4 is electrically connected with the base of the triode Q2, the emitter of the triode Q2 is grounded, one path of the collector of the triode Q2 is electrically connected with one end of the resistor R3, the other path of the collector of the triode Q2 is electrically connected with the base of the triode Q3, one end of the resistor R3 far away from the triode Q2 is electrically connected with the emitter of the triode Q3, and the common connection end between the resistor R3 and the emitter of the triode Q3 is electrically connected with the input end Vin.

As a further preferable technical solution of the above technical solution, the input terminal Vin is electrically connected to the output terminal Vout through a transistor Q1, a collector of the transistor Q3 is electrically connected to one end of a resistor R1, and one end of the resistor R1, which is far away from the transistor Q3, is electrically connected to a base of the transistor Q1.

As a further preferable mode of the above-mentioned technical solution, the input terminal Vin is electrically connected to a collector of the transistor Q1, and the output terminal Vout is electrically connected to an emitter of the transistor Q1.

As a further preferable technical solution of the above technical solution, the base of the transistor Q1 is electrically connected to the cathode of the diode D3, and the anode of the diode D3 is grounded.

Drawings

Fig. 1 is a circuit diagram of a regulated power supply with soft start and ultra-low off current according to the present invention.

Fig. 2 is a circuit diagram of a conventional wide power LDO power supply method.

Fig. 3A is a diagram of a conventional fixed voltage regulator circuit that is powered by a combination of a general triode regulator and a switching circuit.

FIG. 3B is a diagram of a conventional output-adjustable series regulated voltage regulator circuit powered by a combination of a general triode regulator and a switching circuit.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents and other technical solutions without departing from the spirit and scope of the invention.

The utility model discloses a constant voltage power supply with soft start and ultralow turn-off current, combine preferred embodiment below, make further description to utility model's embodiment.

Referring to fig. 1 of the drawings, fig. 1 is a circuit diagram of a regulated power supply with soft start and ultra-low off current according to the present invention, fig. 2 is a circuit diagram of a conventional wide power LDO power supply mode, fig. 3A is a diagram of a conventional fixed voltage stabilizing circuit powered by a combination of a general triode regulated power supply and a switching circuit, and fig. 3B is a diagram of a conventional series regulated voltage stabilizing circuit with adjustable output powered by a combination of a general triode regulated power supply and a switching circuit.

In the embodiments of the present invention, those skilled in the art will note that the resistors, capacitors, and the like according to the present invention can be regarded as the prior art.

Preferred embodiments.

The utility model discloses a constant voltage power supply with soft start and ultralow turn-off current, including input Vin, output Vout and switch circuit, switch circuit respectively with input Vin with output Vout electric connection, wherein:

Specifically, the input terminal Vin is electrically connected to the output terminal Vout through a transistor Q1, a collector of the transistor Q3 is electrically connected to one end of a resistor R1, and an end of the resistor R1 away from the transistor Q3 is electrically connected to a base of the transistor Q1.

More specifically, the input terminal Vin is electrically connected to the collector of the transistor Q1 and the output terminal Vout is electrically connected to the emitter of the transistor Q1.

Further, the base of the transistor Q1 is electrically connected to the cathode of the diode D3 and the anode of the diode D3 is grounded.

Furthermore, the base of the transistor Q1 is electrically connected to one end of a capacitor C1, and one end of the capacitor C1 away from the transistor Q1 is grounded.

The utility model discloses a theory of operation does:

preferably, the circuit of the utility model is a brand-new triode linear voltage stabilizing circuit, which can turn off the output before the system sleeps, and reduce the power consumption. The resistor R4, the triode Q2, the resistor R3 and the triode Q3 are a switch circuit, when CTL _ ON/OFF is high level, the triode Q2 is conducted, the base electrode of the triode Q3 is pulled down to about 0.3V, the triode Q3 is conducted, the voltage of the input end Vin passes through the triode Q3, the resistor R1 provides a stabilized current for the voltage stabilizing diode D3, when the input voltage exceeds 13V, the base electrode voltage of the triode Q1 is maintained to be 13V, the triode Q1 is conducted, and as the voltage between the base electrode of the triode Q1 and the emitter is fixed to be 0.7V, the output voltage of the circuit is equal to the stabilized value of the voltage stabilizing tube minus 0.7V, and 12.3V is output. The capacitor C1 is used to form an electronic filter circuit with the triode, and the amplifying function of the triode is used to obtain the filtering effect of hFE (triode amplifying factor) times at the output end, which is incomparable with the filter capacitor connected at the output end, and simultaneously, the capacitor C1, the resistor R1 and the capacitor C1 can form a soft start circuit with the triode Q1, so that the output is smoother in the power-on process.

Preferably, when CTL _ ON/OFF is low, transistor Q2 is turned OFF, the base of transistor Q3 is pulled to the Vin power supply voltage by resistor R3, transistor Q3 is turned OFF, there is no bias current at the base of transistor Q1 due to the turn-OFF of transistor Q3, transistor Q1 is turned OFF, the power supply to the load is stopped, and when CTL _ ON/OFF is high, the output voltage is 12.3V,120mA, and when CTL _ ON/OFF is low, the output voltage is 0V, the whole circuit has only 33nA of OFF current, which is much lower than the two circuits in the prior art.

It is worth mentioning that the technical features such as the resistor and the capacitor related to the present invention should be regarded as the prior art, and the specific structure, the operation principle of these technical features and the control mode and the space arrangement mode that may be related to adopt the conventional selection in the field, and should not be regarded as the invention point of the present invention, and the present invention does not further specifically expand the detailed description.

It will be apparent to those skilled in the art that modifications and variations can be made in the above-described embodiments, or some features of the invention may be substituted or omitted, and any modification, substitution, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.

Claims

1. A regulated power supply with soft start and ultra-low off current comprises an input end Vin, an output end Vout and a switch circuit, wherein the switch circuit is respectively electrically connected with the input end Vin and the output end Vout, and the switch circuit comprises:

2. A regulated power supply having a soft start and an ultra low off current as claimed in claim 1, wherein said input Vin is electrically connected to said output Vout through a transistor Q1, the collector of said transistor Q3 is electrically connected to one end of a resistor R1, and the end of said resistor R1 remote from said transistor Q3 is electrically connected to the base of said transistor Q1.

3. A regulated power supply having soft-start and ultra-low off-current as claimed in claim 2 wherein said input Vin is electrically connected to the collector of said transistor Q1 and said output Vout is electrically connected to the emitter of said transistor Q1.

4. A regulated power supply having soft-start and ultra-low off current as defined in claim 3 wherein the base of said transistor Q1 is electrically connected to the cathode of diode D3 and the anode of said diode D3 is grounded.

5. The regulated power supply of claim 4 wherein said transistor Q1 has its base further electrically connected to one terminal of a capacitor C1 and said capacitor C1 has its terminal remote from said transistor Q1 grounded.