(a) Field of the Invention
The present invention relates to an MCU integration battery charger/discharger, and more particularly to a charger designed for charging, discharging and supplying electric power to an AA or AAA rechargeable battery, and an MCU and a charging/discharging switch set are provided to integrate a circuit structure with “a separate detection charging circuit and a series-connected and combined discharging circuit.”
(b) Description of the Related Art
As portable 3C electronic products become increasingly more popular, the demand for batteries becomes increasingly higher as well. A disposable battery (or a primary battery) is discarded after use, not only increasing the cost, but also causing environmental pollutions. Therefore, a rechargeable battery (or a secondary battery) has a higher consumption than that of the primary battery since the rechargeable battery can save costs and reduce contaminations of waste batteries.
At present, the rechargeable battery includes lithium-ion (Li-ion) battery, nickel metal hydride (Ni-MH) battery, nickel cadmium (Ni—Cd) battery and the rechargeable alkaline battery, and these batteries are also known as secondary batteries. Recently, a lithium battery with an organic electrolytic unit is used extensively in portable electronic devices due to its features of high-capacity density, low temperature, and stable storage.
However, the lithium battery still has the following drawbacks in its use:
1. The lithium battery usually comes with a different specification for each of the electronic products. Even for the electronic products of the same brand, such as the Nokia mobile phones, there are tens of models of the lithium batteries, and thus causing tremendous inconvenience and trouble to users.
2. The lithium battery contains an electrolytic unit, and there is a safety concern such as possible explosion occurred when a current is passed.
3. Most of the present portable powers use a built-in lithium battery as an energy storage unit, but it generally does not come with a standard size for general electronic consumer products. As a result, the fully charged battery cannot be used alone when it is removed. Even though it can be removed, there are so many specifications of the lithium batteries, and such application is impractical.
Compared with the lithium battery, although the secondary battery such as the nickel metal hydride (Ni-MH), nickel cadmium (Ni—Cd) or alkaline rechargeable secondary battery has an energy storage density less than that of the lithium battery, yet its widely used AA or AAA battery sets an industrial specification, which is the main reason of its popularity up to now. However, its use still has the following insufficiencies:
1. As shown in
2. As shown in
3. In order to improve the above-mentioned charging circuit, the applicant of the invention disclosed a solution of U.S. Pat. No. 6,784,638 “Series Charger with Separate Detection of Batteries” with which a plurality of batteries connected in series can be charged. In addition, a control IC and a separate detection circuit are employed to conduct the detection control of each battery. In this way, the problems of the series charger and the parallel charger may be eliminated. By use of this series charger with separate detection of batteries, the batteries each can be charged and detected if they are fully charged. However, it is not possible as well to discharge the batteries in a series mode for the 3C electronic products. This requires further improvements.
It is a primary object of the present invention to provide an MCU battery integration charger/discharger, and more particularly a series circuit for detecting the battery charging process and for conducting a series-connected and combined discharging process on the same battery charger. Whereby, the stored electric energy can be released for use by the series-connected separate detection charging circuits. Moreover, the charger can deliver DC power via the interface to the 3C electronic products for the charging purpose. Meanwhile, the problems of conventional AA or AAA battery chargers and lithium batteries designed as a portable power are overcome, thereby enhancing the effect and safety of the charger.
Another object of the present invention is to provide an MCU integration battery charger/discharger, serving as a charger when a battery is charged in an independent separate charging mode and removed from the charger for the use by an electronic product, or serving as a discharger when a charging/discharging switch set is switched to a series-connected and combined discharging mode, and a stabilized DC power is outputted for charging a portable electronic product, or serving as an adaptor by supplying a DC charging power when there is no battery placed in the charger or the power of an electronic device is low. In addition, the battery charger becomes a portable power when is carried Out, such that when the power of an electronic device is low, the charger can serve as a backup secondary battery. Even one alkaline primary battery can be placed in the battery charger for the discharging, and thus the battery charger also serves as an emergency power supply.
In order to achieve the above-mentioned objects, the invention includes:
a casing, containing a charging component, and having a charging base disposed on a surface of the casing, a plurality of charging compartments formed in the charging base for placing a plurality of AA or AAA batteries respectively, and an end of the charging compartment being a positive terminal, and the other end of the charging compartment being a negative terminal, thereby creating a charging circuit, and the casing having a plug connectible to an external power source;
a charging circuit, including an exchange power source for converting an AC or DC power to a DC power and supplying a reference voltage source to a charging control unit, and a current control unit and a voltage control unit being interposed between the charging control unit and the exchange power source, thereby creating a charging circuit for charging the batteries in the charging base;
each charging circuit of the batteries within the charging base being connected in parallel with a switch element, and an anti-adverse-current element being interposed between the switch element and the positive terminal of the battery;
a charging/discharging switch set provided for switching the charging circuits into the charging mode or the discharging mode, and the charging/discharging switch set having a number n−1 of switching units (SW1˜SWn-1) corresponding to the charging circuits n in the charging base such that a switching unit is respectively interposed between two charging circuits, and wherein the last switching unit (SWn) of the charging/discharging switch set is an independent charging/discharging control switch, and wherein each of the switching units (SW1˜SWn) has three contacts a, b, c, and wherein the contact a of the switching units (SW1˜SWn-1) is electrically connected to the switch element of the corresponding charging circuits and to the front end of the anti-adverse-current element of the next charging circuits, and wherein the contact b is electrically connected to the positive terminal of the battery of the next charging circuit, and wherein the contact c is electrically connected to the negative terminal of the battery of the corresponding charging circuit, and wherein the contact a of the switching unit (SWn) serving as the charging/discharging control switch is not only a ground connection but a charging control terminal, and the contact b is a discharging control terminal connecting to a power control terminal (VDD), and the contact c is connected to the charging control unit by a first connecting wire;
a voltage regulator circuit, being coupled to a positive terminal of the first charging circuit/compartment in the charging base for boosting or stepping down the series-connected and combined discharging current of each battery to a predetermined DC voltage;
an output port, coupled to an output terminal of the voltage regulator circuit;
a feedback current, being fed back discharging current of a part of the battery from the output terminal of the charging base to the reference voltage source and the charging control unit by a second connecting wire while the battery is discharging; and
a discharging button, exposed from a surface of the casing, and electrically connected to the charging control unit while the charging control unit is connected to the voltage regulator circuit by a third connecting wire for controlling the discharging current outputting the voltage regulator circuit to the output port;
whereby, when the battery is set in the charging base, the charging/discharging control switch is in a LOW voltage level, and the charging control unit controls n sets of switching units (SW1˜SWn) to synchronously turn each contact c and each contact a ON, such that each battery of the charging circuit is in a separate detection charging mode, and when the each battery is fully charged, the charging/discharging control switch is in a HIGH voltage level, and the charging control unit controls n sets of switching units (SW1˜SWn) to synchronously turn each contact c and each contact b ON, such that each battery of the charging circuit is in a series-connected and combined synchronous discharging mode, and the discharging button is provided for controlling the ON/OFF of the discharging current from the voltage regulator circuit.
According to the above-mentioned technical features, the charging base has n sets of charging circuits, and n is equal to 2, 4 or 8, and the n−1 sets of the switching units (SW1˜SWn-1) corresponding to the charging/discharging switch set is equal to 1 set, 3 sets or 7 sets, and the 1 set, 3 sets or 7 sets plus the last nth set of independent switching unit (SWn) form the charging/discharging control switch.
According to the above-mentioned technical features, the charging/discharging switch set is constructed as an electronic type switch which is comprised of a MOSFET or a logic circuit.
According to the above-mentioned technical features, the exchange power source is externally coupled to a DC To DC power supply for supplying the power to the output port.
According to the above-mentioned technical features, a current detector circuit is composed between the current detection component and the current control unit, and the current detector circuit is electrically connected to the current control unit.
According to the above-mentioned technical features, a discharging (enable) switch is built in the voltage regulator switch.
According to the forgoing techniques, the present invention is provided and integrated with the MCU and the charging/discharging switch set for constituting a circuit structure featuring an “separate detection charging and series-connected and combined discharging mode” without increasing the volume of the charger so as to overcome the problems of conventional chargers for nickel metal hydride batteries and nickel cadmium batteries and the problems of lithium batteries designed as a portable power, and to enhance the effect and safety of the charger.
With reference to
The charging base 12 as shown in
With reference to
A charging circuit 14 includes an exchange power source 20 for converting an AC or DC power to a DC power and supplying a reference voltage source 21 to a charging control unit 22, thereby creating the charging circuit 14 for charging the batteries B1˜B4 in the charging base 12. The charging control unit 22 is an MCU of a microcomputer, and each component of the charging circuit 14 is operated by executing a predetermined sequence of procedures.
A current control unit 23 and a voltage control unit 24 are interposed between the input terminal of the charging control unit 22 and the exchange input power source 20, and a switch 29 is installed between them. The charging circuit 14 composed of the foregoing components is a prior art, and thus will not be described here.
A current detection component 28 is coupled to a negative terminal 12b of the charging base 12, and the current detection component 28 can be a resistor R and coupled to the current and voltage control units 23, 24 for detecting current by the charging of the charging base 12 and using it as a voltage feedback current control to make adjustments.
As shown in
The charging control unit 22 separately applies a terminal voltage to the positive terminals of the batteries of the charging circuits 121˜124 for the purpose of detection. As shown in
The series charging circuit in accordance with the invention differs from the prior art in that the batteries each can be separately detected if they are fully charged when they are charged in a series-connected state and that they are changed into the discharge mode when they are fully charged. In order to achieve these effects, a circuit arrangement specially designed is required. According to the present invention, an MCU and a charging/discharging switch set 30 are employed to achieve the expected effect of series combination discharge. In other words, the negative terminal of the battery B1 of the first charging circuit 121 in accordance with the present invention is not directly connected to the positive terminal of the battery B2 of the second charging circuit 122. This also applies to the third and fourth charging circuits 123, 124. According to the invention, the charging/discharging switch set 30 has to be interposed between the charging circuits 121˜124 for conducting different switching functions.
The charging/discharging switch set 30 in accordance with the present invention is constructed as an electronic type switch which can be a MOSFET or logic circuit while the charging control unit 22 is used to control the ON/OFF state of the charging/discharging switch set 30. The contacts a, b, c of the switching units SW1˜SW4 of the charging/discharging switch set 30 have the same connection way and the same synchronous switching control way. That is, the last switching unit SW4 is used as a charging/discharging control switch 31.
The charging/discharging switch set 30 is internally provided with a number n−1 of switching units SW1˜SWn-1 corresponding to the charging circuits 121˜12n, n=4 such that a switching unit is respectively interposed between two adjacent charging circuits, for example between the first and second charging circuits 121˜122 while the last switching unit SWn of the charging/discharging switch set 30 is an independent charging/discharging control switch 31. Moreover, each of the switching units SW1˜SWn has three contacts a, b, c. The contact a of the switching units SW1˜SWn-1 is electrically connected to the switch elements Q1˜Q3 of the charging circuits 121˜123 and the front end of the anti-adverse-current element D2˜D4 of the next charging circuits. The contact b of the switching units SW1˜SWn-1 is connected to the positive terminal of the battery of the next charging circuit. For example, the switching unit SW1 is connected to the positive terminal of the battery B2, and the switching unit SW3 is connected to the positive terminal of the battery B4. In addition, the contact c of the switching units SW1˜SWn-1 is electrically connected to the negative terminal of the battery of the corresponding charging circuit 121˜123. The negative terminal of the last charging circuit 124 is grounded. A preferred embodiment of the present invention may have n sets of charging circuits in the charging base, wherein n is equal to 2, 4 or 8, and n−1 sets of switching units SW1˜SWn-1 corresponding to the charging/discharging switch set 30 include 1 set, 3 sets or 7 sets, and the last nth set of independent switching unit SWn may be added to the 1 set, 3 sets or 7 sets to serve as the charging/discharging control switch 31.
A feedback current Ib is a discharging current Id of a part of the batteries for feeding back from the output terminal of the charging base 12 to the reference voltage source 21 and the charging control unit 22 by a second connecting wire 41 while the battery is discharging.
A discharging button 40 is exposed from a surface of the casing 11 and electrically connected to the charging control unit 22 while the charging control unit 22 is connected to a voltage regulator circuit 50 by a third connecting wire 42 for controlling the discharging current Id outputting from the voltage regulator circuit 50 to the output port 60. In this preferred embodiment, the voltage regulator circuit 50 is a synchronous buck/boost DC/DC converter, and the buck/boost IC technology of this sort has been used extensively, and can provide a stable and accurate voltage output, and its internal circuit is a prior art and thus will not be described in details here.
Since four pieces of nickel metal hydride/cadmium secondary batteries B1˜B4 connected in series can only provide a voltage of 1.2Vx4=4.8V which is still below the standard USB power output of DC 5.0V, therefore, it is necessary to step up the voltage. Since the voltage of the alkaline primary battery is 1.5V, and four of them provide a total voltage of 6V, therefore the discharging current is different from the secondary battery and requires stepping down the voltage from 6V to 5V. On the other hand, the present invention adopts the foregoing voltage regulator circuit 50 that can discharge, step up, step down or regulate the voltage for different batteries, so as to assure that the electric power supply from the USB output port 60 has a stable and accurate voltage.
When the batteries B1˜Bn are set in the charging base 12, the charging/discharging control switch 31 is in a LOW voltage level, and the charging control unit 22 controls n sets of switching units SW1˜SWn to synchronously turn each of the contacts c and each of the contacts a ON, such that the battery B1˜Bn on each charging circuit 121˜124 is in an independent separate charging mode. When the batteries B1˜Bn are fully charged, the charging/discharging control switch 31 is in a HIGH voltage level, and the charging control unit 22 controls n sets of switching units SW1˜SWn to synchronously turn each of the contacts C and each of the discharging contacts b ON, such that the battery B1˜Bn on each charging circuit 121˜124 is in a series-connected and combined discharging mode. The discharging button 40 controls the ON/OFF state of the discharging current Id by voltage regulator circuit 50,
Based on the technical features disclosed, when the batteries B1˜B4 are set in the charging base 12, the charging/discharging control switch 31 is in a LOW voltage level, and the charging control unit 22 turns each of the contacts a ON. At the same time, the charging/discharging switch set 30 switches to a charging mode, such that each of the batteries B1˜B4 is synchronously charged. When the batteries B1˜B4 are fully charged, the charging/discharging control switch 31 is in a HIGH voltage level, and the charging control unit 22 turns each of the contacts b ON. At the same time, the charging/discharging switch set 30 switches to a discharging mode, such that each of the batteries B1˜B4 is in a series-connected and combined discharging mode as shown in
To charge the electronic devices, then press the discharging button 40. At this time, the discharging control unit 22 controls a discharging (enable) switch 51 built in the voltage regulator circuit 50 to be in the ON state, such that the discharging current Id is output to the output port 60 for the use of the external electronic devices.
The MCU integrated series-connected charger/discharger in accordance with the aforesaid preferred embodiment is not a limitation. That is, the structure of the MCU integration charger/discharger in accordance with the present invention can be a parallel-connected charger as shown in the
With the foregoing structures as shown in
With reference to
With reference to
With reference to
With reference to
With reference to
In summation, the present invention uses an MCU and a charging/discharging switch set to integrate the features of an “independent separate charging circuit” and a “series-connected and combined discharging circuit” to synchronously, control the ON/OFF of the charging and discharging circuits in the same charging base. The invention not only provides a convenient operation, but also overcomes the shortcomings of the conventional charger and achieves the effects of enhancing the charging and discharging performance, and integrating several functions into the same charger to improve its practicability.
Many changes and modifications in the above-described embodiments of the invention can, of course, be carried out without departing from the scope thereof. Accordingly, to promote the progress in science and the useful arts, the invention is disclosed and is intended to be limited only by the scope of the appended claims.