CN209860651U

CN209860651U - Lithium battery charger circuit

Info

Publication number: CN209860651U
Application number: CN201920648071.0U
Authority: CN
Inventors: 罗年生
Original assignee: Shenzhen Senhaiwei Electronics Co Ltd
Current assignee: Shenzhen Senhaiwei Electronics Co Ltd
Priority date: 2019-05-08
Filing date: 2019-05-08
Publication date: 2019-12-27
Anticipated expiration: 2029-05-08

Abstract

The utility model discloses a lithium battery charger circuit, which comprises a self-excited switch power supply circuit allowing AC110-220V voltage input range and a charging management circuit taking HT3582DM type universal charger control chip as core; the alternating current power supply is connected with the input end of the self-excitation type switch power supply circuit; the output end of the self-excited switch power supply circuit is connected with the input end of the charging management circuit; the output end of the charging management circuit is connected with the lithium battery; the utility model discloses a charging management circuit uses HT3582DM type universal charger control chip as the core, and it adopts the constant voltage charging mode, and charging current is the continuation linearity, and battery voltage basically can not become sluggish after the charging, and the battery can be filled very fully, and the battery is more durable, and does not have the problem of short time during charging and recharging; the circuit topology structure is simplified, the manufacturing cost is low, and the application value is good.

Description

Lithium battery charger circuit

Technical Field

The utility model relates to charging circuit technical field especially involves a lithium battery charger circuit.

Background

Lithium battery chargers are chargers that are used exclusively to charge lithium ion batteries. The lithium ion battery has higher requirement on the charger and needs a protection circuit, so the lithium ion battery charger generally has higher control precision and can charge the lithium ion battery at constant current and constant voltage.

The charging voltage is switched off in a pulse mode, the charging current fluctuates in a pulse mode (the service life of the battery is greatly related to the charging and discharging times, the battery is easily charged in the charging mode, the service life of the battery is shortened), the voltage of the battery is generally reduced by about 100mV after the charging is finished, and the problem of quick recharging is easily caused.

Accordingly, the prior art is deficient and needs improvement.

SUMMERY OF THE UTILITY MODEL

The utility model provides a lithium battery charger circuit, the above-mentioned problem of solution.

In order to solve the above problem, the utility model provides a technical scheme as follows:

a lithium battery charger circuit comprises a self-excited switching power supply circuit allowing an AC110-220V voltage input range and a charging management circuit taking an HT3582DM type universal charger control chip as a core; the alternating current power supply is connected with the input end of the self-excitation type switch power supply circuit; the output end of the self-excited switch power supply circuit is connected with the input end of the charging management circuit; the output end of the charging management circuit is connected with the lithium battery.

Compared with the prior art, the beneficial effects are that, adopt above-mentioned scheme, the utility model discloses a charge management circuit uses HT3582DM type universal charger control chip as the core, and it adopts the constant voltage charging mode, and charging current is the continuation linearity, and battery voltage basically can not stagnate after the charging, and the battery can be filled very fully, and the battery is more durable, and does not have the problem that the short time recharges during charging; the circuit topology structure is simplified, the manufacturing cost is low, and the application value is good.

Drawings

For a clearer explanation of the embodiments or technical solutions in the prior art, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic circuit diagram of a lithium battery charger circuit according to the present invention.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described in more detail with reference to the accompanying drawings and specific embodiments. Preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The use of the terms "fixed," "integrally formed," "left," "right," and the like in this specification is for illustrative purposes only, and elements having similar structures are designated by the same reference numerals in the figures.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

As shown in fig. 1, an embodiment of the present invention is:

The self-excited switching power supply circuit comprises resistors R1-R3, capacitors C1-C4, diodes D1-D4, a triode Q1 and a transformer T1.

The N end of the alternating current power supply is connected with the anode of the diode D1; the cathode of the diode D1 is respectively connected with the first end of the capacitor C1, the 1 st tap of the transformer T1 and the first end of the resistor R1; a second end of the resistor R1 is respectively connected with a second end of the resistor R2, a base electrode of the triode Q1 and a negative electrode of the diode D2; a first end of the resistor R2 is connected with a second end of the capacitor C2; a first end of the capacitor C2 is respectively connected with the cathode of the diode D3 and the 3 rd tap of the transformer T1; the anode of the diode D3 is connected to the anode of the diode D2 and the second end of the capacitor C3; the emitter of the transistor Q1 is connected with the second end of the resistor R3; the collector of the triode Q1 is connected with the 2 nd tap of the transformer T1; the L end of the alternating current power supply is respectively connected with the second end of the capacitor C1, the first end of the capacitor C3, the first end of the resistor R3 and the 4 th tap of the transformer T1; a 6 th tap of the transformer T1 is connected with a first end of the capacitor C4; the 5 th tap of the transformer T1 is connected with the anode of the diode D4; the cathode of the diode D4 is connected to the second terminal of the capacitor C4.

The allowable voltage input range of the alternating current power supply is AC 110-220V; the allowable frequency input range of the alternating current power supply is 47-63 Hz.

Diode D2 is a zener diode; the transistor Q1 is an NPN transistor of 13001 type.

The transformer T1 is a high frequency transformer.

The charge management circuit comprises capacitors C5-C6, a light emitting diode LED and an integrated circuit U1.

The first end of the capacitor C4 is respectively connected with the first ends of the capacitors C5-C6, the anode of the light-emitting diode LED and the 5 th-6 th pins of the integrated circuit U1; the second end of the capacitor C5 is respectively connected with the positive electrode of the lithium battery and the 7 th pin of the integrated circuit U1; the second end of the capacitor C4 is connected with the 8 th pin of the integrated circuit U1; the second end of the capacitor C6 is connected with the 1 st pin of the integrated circuit U1 and the negative electrode of the lithium battery; the 3 rd-2 nd pin of the integrated circuit U1 is sequentially connected with the first and second cathodes of the light emitting diode LED respectively.

The lithium battery is a 3.7V single-section lithium ion battery; the light emitting diode LED is a bicolor light emitting diode.

The integrated circuit U1 is a HT3582DM type universal charger control chip.

Battery detection

When the battery is accessed in the case of power supply disconnection, HT3582DM controls the battery accordingly through an automatic 'polarity identification' system. The charger status indicated by the light emitting diode LED at this time is as follows:

state description Power State Battery State L2L 3

Normal on-off of battery detection disconnection

Battery no-load connection disconnection dimming

Trickle charge access normal access flash-off

Normal charging access normal access flash-off

Saturation detection access normal access de-illumination

A pre-charge function;

when the power supply is connected and connected to the battery, if the voltage difference between the two ends of the battery BTP and BTN is less than 2.3V (typical value), the power supply pre-charges the battery with a small current (25 mA typical value) through HT3582D, and normal charging is started when the voltage of the battery rises to 2.3V.

Normal charging and saturation detection:

the power supply is connected and is connected with a less full battery (the battery voltage is less than 4.13V (typical value)), the power supply starts to charge the battery under the control of HT3582D, the charging current is about 300mA (typical value), the voltage at two ends of the battery is gradually increased, when the battery voltage is increased to 4.23V (typical value), the battery is close to saturation, and then the constant-voltage small-current supplementary charging mode is switched in. The battery is only recharged when the battery voltage is <4.13V (typical value).

Short-circuit protection:

if a battery short occurs after power is turned on, the HT3582DM internal "short protection" system will automatically reduce the charging current to 25mA (typical value). At this time, if the battery is accessed again with the correct polarity, the battery can still be charged normally.

And (3) over-temperature protection:

if the junction temperature of the chip exceeds TO (150 ℃ typical value) during charging, the internal over-temperature protection system can automatically reduce the charging current until the junction temperature is reduced TO TR (120 ℃ typical value), and the IC recovers the normal charging state.

The utility model discloses a theory of operation:

when the power supply is switched on, starting current is provided for the switching tube Q1 at R1, so that Q1 is conducted, the collector current Ic of the Q3526 linearly increases in a coil between taps 1-2 of the transformer, positive feedback voltage which enables the base of the Q1 to be positive and the emitter to be negative is induced in the coil between taps 3-4 of the transformer, and the Q1 is quickly saturated. At the same time, the induced voltage charges C2, and as the charging voltage of C2 increases, the base potential of Q1 gradually becomes lower, so that Q1 exits the saturation region, Ic begins to decrease, a voltage which enables the base of Q1 to be negative and the emitter to be positive is induced in the coil between the taps of 3-4 of the transformer, so that Q1 is cut off rapidly, at the moment, the diode D4 is conducted, and the stored energy in the primary winding of the high-frequency transformer T1 is released to the load. When the Q1 is cut off, no induced voltage exists in a coil between taps of the transformer 3-4, the DC power supply and human power transmission voltage reversely charges the C2 through the R1, the base potential of the Q1 is gradually increased to be conducted again, the circuit is turned over again to reach a saturation state, and the circuit repeatedly oscillates. Here, as in the case of the single-ended flyback switching power supply, the required voltage is output to the load from the secondary winding of the transformer T1.

After the charging management circuit is powered by the power supply, the lithium ion battery is precharged and normally charged, and the charging is automatically stopped until the terminal voltage of the lithium ion battery reaches 4.2V.

It should be noted that the above technical features are continuously combined with each other to form various embodiments which are not listed above, and all the embodiments are regarded as the scope of the present invention described in the specification; moreover, modifications and variations will occur to those skilled in the art in light of the foregoing description, and it is intended to cover all such modifications and variations as fall within the true spirit and scope of the invention as defined by the appended claims.

Claims

1. A lithium battery charger circuit is characterized by comprising a self-excited switching power supply circuit allowing an AC110-220V voltage input range and a charging management circuit taking an HT3582DM type universal charger control chip as a core; the alternating current power supply is connected with the input end of the self-excitation type switch power supply circuit; the output end of the self-excited switch power supply circuit is connected with the input end of the charging management circuit; the output end of the charging management circuit is connected with the lithium battery; the self-excited switching power supply circuit comprises resistors R1-R3, capacitors C1-C4, diodes D1-D4, a triode Q1 and a transformer T1.

2. The lithium battery charger circuit as claimed in claim 1, wherein the N terminal of the ac power source is connected to the anode of a diode D1; the cathode of the diode D1 is respectively connected with the first end of the capacitor C1, the 1 st tap of the transformer T1 and the first end of the resistor R1; a second end of the resistor R1 is respectively connected with a second end of the resistor R2, a base electrode of the triode Q1 and a negative electrode of the diode D2; a first end of the resistor R2 is connected with a second end of the capacitor C2; a first end of the capacitor C2 is respectively connected with the cathode of the diode D3 and the 3 rd tap of the transformer T1; the anode of the diode D3 is connected to the anode of the diode D2 and the second end of the capacitor C3; the emitter of the transistor Q1 is connected with the second end of the resistor R3; the collector of the triode Q1 is connected with the 2 nd tap of the transformer T1; the L end of the alternating current power supply is respectively connected with the second end of the capacitor C1, the first end of the capacitor C3, the first end of the resistor R3 and the 4 th tap of the transformer T1; a 6 th tap of the transformer T1 is connected with a first end of the capacitor C4; the 5 th tap of the transformer T1 is connected with the anode of the diode D4; the cathode of the diode D4 is connected to the second terminal of the capacitor C4.

3. The lithium battery charger circuit as claimed in claim 2, wherein the allowable voltage input range of the AC power supply is AC 110-220V; the allowable frequency input range of the alternating current power supply is 47-63 Hz.

4. A lithium battery charger circuit as claimed in claim 1 or 2, characterized in that the diode D2 is a zener diode; the transistor Q1 is an NPN transistor of 13001 type.

5. The lithium battery charger circuit as claimed in claim 4, wherein the transformer T1 is a high frequency transformer.

6. The lithium battery charger circuit as claimed in claim 1, wherein the charge management circuit comprises capacitors C5-C6, light emitting diodes LED and an integrated circuit U1.

7. The circuit of claim 6, wherein the first terminal of the capacitor C4 is connected to the first terminals of the capacitors C5-C6, the anode of the light emitting diode LED, and the 5 th-6 th pins of the integrated circuit U1, respectively; the second end of the capacitor C5 is respectively connected with the positive electrode of the lithium battery and the 7 th pin of the integrated circuit U1; the second end of the capacitor C4 is connected with the 8 th pin of the integrated circuit U1; the second end of the capacitor C6 is connected with the 1 st pin of the integrated circuit U1 and the negative electrode of the lithium battery; the 3 rd-2 nd pin of the integrated circuit U1 is sequentially connected with the first and second cathodes of the light emitting diode LED respectively.

8. The lithium battery charger circuit of claim 7, wherein the lithium battery is a 3.7V single-cell lithium ion battery; the light emitting diode LED is a bicolor light emitting diode.

9. The lithium battery charger circuit as claimed in claim 6 or 7, wherein the integrated circuit U1 is a HT3582DM universal charger control chip.