MXPA96005240A

MXPA96005240A - Apparatus and method for downloading and charging a multip battery disposal

Info

Publication number: MXPA96005240A
Application number: MXPA/A/1996/005240A
Authority: MX
Inventors: D Mottier Matthew; H Barkat Shakil; Ng Richard
Original assignee: Motorola Inc
Priority date: 1995-10-31
Filing date: 1996-10-30
Publication date: 1997-06-01

Abstract

The present invention relates to an electronic device that is powered in a state of operation by a battery arrangement, the battery arrangement comprises a first battery and a second battery, the electronic device comprising: a detector for monitoring a voltage level of the first battery and the second battery, a first switch for coupling to another of the first battery and the second battery and the detector, the first switch operable to connect another of the first battery and the second battery to power the electronic device without interruption in the operating state when the voltage level of the first battery and the second battery from the power supply of the electronic device without interruption in the operating state when the voltage level of the first battery and the second battery is above the voltage level default, and a second switch to connect to one of the prim It was battery and second battery and to connect the first of the first battery and the second battery to power the electronic device even though the voltage level of the first battery and the second battery is above a certain voltage level.

Description

APPARATUS AND METHOD FOR DOWNLOADING AND CHARGING A DISPOSAL OF MULTIPLE BATTERIES Background of the Invention 1. Field of the Invention This invention relates generally to batteries and more specifically to a multiple battery arrangement that powers a device. 2. Description of Related Art Portable electronic devices powered by batteries have become increasingly popular due to their low weight and compactness. These devices, for example cellular radiotelephones and laptops, are generally equipped with a single main battery and, therefore, their operating time is short. Also, the operation of devices must be interrupted to replace the only main battery. These interruptions can occur at unwanted times - during a call on a cellular radiotelephone or while processing data by computer - and produce unwanted results - call cutoff or data loss.

In response to these disadvantages, portable electronic devices have been equipped with an auxiliary battery. These portable electronic devices automatically switch between the main and auxiliary batteries to avoid interruption in operation. For example, when the main battery runs out, the device switches to the auxiliary battery.

The main battery can then be replaced. Once replaced, the device switches back to the main battery when the auxiliary battery runs out, and so on. You can imagine the perpetual operation of the portable electronic device if the replacement of the battery packs is maintained. Unfortunately, these devices do not allow the user to replace the current battery without interrupting the operation of the device. Replacement is limited to the exhausted battery after switching occurs.

Likewise, an additional hardware is necessary to carry out the switching of a multiple battery arrangement. For example, a prior art device requires an additional voltage detector, a scale circuit, and numerous additional switches to accommodate the auxiliary battery. This increases the cost, complexity and size of the device.

What is needed then is a more economical apparatus and method for downloading a multiple battery arrangement in a form that allows continuous uninterrupted operation of a device.

Brief Description of the Figures Fig. 1 is an illustration of a front, top and right side perspective view of a portable electronic device in the open position with a main battery and an auxiliary battery mounted thereon. Fig. 2 is an illustration of a rear, top and left side perspective view of a portable electronic device in closed position with the main battery and the auxiliary battery disassembled from it. Fig. 3 is a block diagram illustration of a radio frequency communication system employing the portable electronic device of Fig. 1, the portable electronic device has a discharge and charge circuit.

Fig.4 is an illustration in block diagram form of the discharge and charge circuit of Fig.3. Fig.5 is a partial schematic illustration of the discharge and charge circuit of Fig.3. Fig.6 is an illustration in the form of a flow diagram of a method for discharging the main battery and the auxiliary battery. Fig.7 is an illustration in diagrammatic form of a method for charging the main battery and the auxiliary battery. Fig.8 is an illustration in diagrammatic form of a method for determining which of the main battery and the auxiliary battery is to be changed.

Detailed Description of the Preferred Embodiments A discharge circuit placed inside a portable electronic device feeds the device by selecting between removable main and auxiliary batteries mounted on the device. The circuit includes a detector that monitors the voltage level of the auxiliary battery. The discharge circuit includes a discharge switch connected between the main battery and the device. When both batteries are mounted, the energy is supplied by the auxiliary battery until it is discharged to a predetermined voltage. Once the predetermined voltage has been reached, the discharge switch connects the main battery to power the device. The main battery is connected without interrupting the operation of the device. If the main battery is removed while the device is being powered, the auxiliary battery powers the device without interruption and without taking into account the fact that it is discharged up to the predetermined voltage. If the auxiliary battery is replaced while the main battery is powering the device, the discharge switch disconnects the main battery and connects the auxiliary battery to power the device (assuming that the voltage level of the auxiliary battery is above the predetermined voltage ). By using this discharge priority, ie by first discharging the auxiliary battery, circuits can be minimized and the uninterrupted operation of the device can be maintained.

The discharge circuit is associated with a charging circuit located in the device that charges the removable main and auxiliary batteries mounted to the device. The charging circuit includes detector circuits, a circuit switch and current generation circuits for generating a load current. The detector circuits detect whether the main and auxiliary batteries are mounted in the device. The load switch is connected to the detector circuits, the current generation circuits and the main and auxiliary batteries. When both batteries are mounted, the load switch initially connects the current generating circuits to fully charge the main battery and then connects the current generating circuits to charge the auxiliary battery. If the main battery is replaced while the auxiliary battery is being charged, the charge switch immediately reconnects the current generating circuits to fully charge the main battery.

Fig. 1 illustrates a portable electronic device 100 having a main battery 101 and an auxiliary battery 102. The device 100, which is preferably a radiotelephone, includes a cabinet 104 having a lower cabinet portion 106 and an upper cabinet portion. 108 rotatably connected by means of an articulation 110. The lower cabinet portion 106 includes a retaining slot 123 for mounting the auxiliary battery 102, a screen 128, a keyboard 130 and a microphone hole 131. The screen 128 provides information visual to the user including, for example, the amount of charge current remaining in the main battery 101 or the auxiliary battery 102. The keypad 130 allows the user to turn the device 100 on and off and initiate calls by entering and sending numbers. A microphone (not shown) is concealed behind the microphone hole 131. The cabinet portion 108 includes a speaker bezel 142 having holes with a speaker (not shown) positioned behind it. In addition to providing voice to the user, the speaker can provide one. audible alarm when the main and auxiliary batteries 101 and 102 are close to being depleted. The lower and upper cabinet portions 106, 108 include the auxiliary and main batteries 101,102 mounted thereon. The main and auxiliary batteries 101,102 can be removed from the device 100 as exemplified in Fig.2.

Fig.2 illustrates the device 100 in closed position with the main and auxiliary batteries 101,102 removed from it. The main battery 101 includes a latch member 202 located at a midpoint of a flange 204 that forms a first end of the main battery 101. A ridge 206 is longitudinally located at a second end of the main battery 101 opposite the bolt member 202. The device 100 includes a first cavity 210 formed in the upper cabinet portion 108. The first cavity 210 is formed by a front wall 211, a right wall 212, a left wall 214 and a back wall 216. A flash 218 extends outwardly from the rear wall 216 and above the first cavity 210. A contact bolt member 222 includes bras 226.228 and comprises a cutting area 224 of the front wall 211. A second cavity 230 of the upper cabinet portion 108 extends forward and above the front wall 211. The main battery 101 is mounted on the device by inserting the flange 206 of the main battery 1 01 below the burr 218 as shown with the dotted line 231 and rotating the main battery 101 downwardly in the first cavity 210. The main battery 101 is rotated until the bolt member 202 is engaged with the brassieres 226.228 contact bolt member 222 and flange 204 rests on second cavity 230. Main battery 101 is removed by pressing bolt member 202 out of holders 226.228 and rotating main battery 101 up and out of the first and second cavities 210,230.

The auxiliary battery 102 includes a flexible latch bolt and fixed supports 234,236 with fasteners 238,240, respectively. The device 100 includes a retention slot 123 of Fig. 1 and receptacles 242, 244 placed on an end 246 of the lower cabinet portion 106 for mounting the auxiliary battery 102. The device 100 includes an elongated hole 248 located at a lower end 246 of the lower cabinet portion 106 between the receptacles 242,244. The elongated hole 248 gives access to a connector 314 (see Fig.3) located therein. The auxiliary battery 102 is assembled by inserting the flexible latch bolt 232 into the retaining groove 123; extending the auxiliary battery 102 at an angle downwardly until the fixed supports 234,236 release the lower end 246; rotating auxiliary battery 102 to overlap with lower cabinet portion 106; and releasing the auxiliary battery 102 thus allowing the fixed supports 234,236 to move towards the lower end 246 allowing the fixings 238,240 to be inserted into the receptacles 242,244 as telegraphed by the lines 250. The space of the fixed supports 234,236 prevents the obstruction of the orifice elongate 248 and maintains access to connector 314 when auxiliary battery 102 is mounted. The auxiliary battery 102 is removed from the device 100 by substantially maintaining the aforementioned mounting steps.

Although the device 100 is illustrated and described as a radiotelephone, it will be recognized that any of the numerous electronic devices, for example, laptops, smoking cameras, pagers, bi-directional radios, personal digital calendars and the like could use the apparatus and method for downloading and charging a multiple battery arrangement as described from here.

Fig. 3 is an illustration in block diagram form of a radio frequency communication system 300 in which a base station 301 and the device 100 communicate by radio frequency (RF) signals 302. The device 100 includes an antenna 303. , a receiver 304, a transmitter 305, a controller 306 and a user interface 308 that includes the speaker (not shown) and the screen 130 of FIG. Controller 306 could be, for example, a 68HC11 microprocessor available from Motorola Inc. Device 100 is powered by removable main and auxiliary batteries 101, 102 and operates as follows. The antenna 303 transduces the radiofrequency signals 302 to electric radio frequency reception signals and connects the electric radio frequency reception signals to the receiver 304. The receiver 304 transforms the electric radio frequency reception signals into data reception signals which are then connected through the controller 306 and the output with the user as voice sound by means of the speaker and as operational information by means of the screen 128. The voice and data input by the user by the microphone and the keyboard 130, respectively, are connected to the transmitter 305 as data transmission signals. The transmitter 305 converts the data transmission signals into electrical radio frequency transmission signals that are transduced by the antenna 303 and transmitted as radio frequency signals 302.

The device 100 includes a discharge and charge circuit 310, a memory 312 and a connector 314. The discharge and charge circuit 310 selectively discharges the main and auxiliary batteries 101,102 to supply uninterrupted power to the device 100. The discharge and charge circuit 310 it also selectively charges the main and auxiliary batteries 101, 102 under the control of a program executed by the controller 306. The program is stored in the memory 312. The memory 312 is preferably a read-only memory (ROM), but it could be a read-only memory. programmable erasable (EPROM), a random access memory (RAM), or another suitable memory device. Although the memory 312 is shown separate from the controller 306, it will be recognized that the memory 312 could be inside the controller 306 and / or that the controller 306 may contain other memory in addition to the memory 312. The connector 314 allows a user to mount a source of external power 430 (see Fig.4) to supply power to operate the device 100 (and save battery charge) or charge the main and auxiliary batteries 101,102.

Fig. 4 also illustrates, in the form of a block diagram, the main and auxiliary memories 101, 102, the discharge and charge circuit 310, the connector 314 and the controller 306. The main and auxiliary batteries 101, 102 are detachably connected in the discharge and charging circuit 310. Main battery 101 includes a main electrochemical cell 404, a main memory 402 and a main thermistor 406. It will be recognized that the main electrochemical cell 404, as illustrated, represents one or more electrochemical cells. The electrochemical cell 404 includes a main positive terminal 405 and a major negative terminal 407. The main electrochemical cell 404 is preferably rechargeable. The electrochemical cell 404 is preferably one of the following types: Nickel-Cadmium (NiCd), Nickel-Metal Hydride (NiMH), Alkaline or Lithium Ion. The main memory 402 is preferably 1 an EPROM. The main memory 402 characterizes the main battery 101 as an "intelligent battery" since the main memory 402 stores data that can be used to optimize the discharge and charge. These data include battery type data, discharge / load hysteresis data and history data. The main thermistor 406 is connected to the main negative terminal 407 and indicates the temperature of the main electrochemical cell 404 by means of voltage drop across it. The main negative terminal 407 is also connected to an electrical ground 409.

The auxiliary battery 102 is similar to the main battery 101 and includes an auxiliary memory 410, an auxiliary electrochemical cell 412 having an auxiliary positive terminal 413 and an auxiliary negative terminal 415 and an auxiliary thermistor 414. The negative axillary terminal 415 is also connected to the electrical ground 409. In the preferred embodiment, however, the auxiliary battery 102 has greater capacity than the main battery 101 and is capable of supplying power for longer periods of time.

A discharge portion of the discharge and charge circuit 310 switchably connects the main and auxiliary batteries 101,102 to a supply line 408 (indicated as B +). The main and auxiliary batteries 101,102 supply the power line 408 with a voltage between 2.8 V and 5.5 V. The supply line 408 of the device supplies the controller 306, the receiver 304 of FIG. 3, the transmitter 305 of FIG. 3, the user interface of FIG. 3 and other components of the device 100 by means of electrical connections (not shown). The discharge portion mainly includes an auxiliary battery switch 420, a detector 422 and a main battery switch 424. The auxiliary battery switch 420 is exclusively associated with the auxiliary battery 102 and operates to connect the auxiliary battery 102 to power the device. 100. An auxiliary battery switch input 420 is connected to the auxiliary positive terminal 413 via line 416. An output of the auxiliary battery switch 420 is connected to the supply line 408 of the device.

The detector 422 is connected between the main and auxiliary batteries 101,102 and detects when the auxiliary battery 102 has discharged below a threshold level and when an external supply 430 has been mounted to the device 100. In the preferred embodiment, the threshold voltage is 3.3 V. The auxiliary positive terminal 413 is connected to the input of the detector 422 on the line 421. The main positive terminal 405 is connected to the second detector input 422 on the line 423. The connector 314 is connected to a third input of detector 422 on line 425. An output of detector 422 is connected to main battery switch 424 and controller 306 on line 426.

The main battery switch 424, in response to the detector 422, connects or disconnects the main battery 101 as a power source from which the device 100 can operate. A first input of the main battery switch 424 is connected to the output of the detector 422 on the line 426. A second input of the main battery switch 424 is connected to the main positive terminal 405 on the line 427. An output of the main battery switch 424 is connected to the power line 408 of the device.

The controller 306 also connects the output of the detector 422 to the user interface 308 of Fig.3. The user interface 308 interprets the output of the detector 422 and informs the user which of the main or auxiliary batteries 101,102 is feeding the device 100 at a particular time. 1 The discharge portion of the discharge and charge circuit 310 discharges the main and auxiliary batteries 101,102 according to a predetermined priority - when both batteries are mounted, the auxiliary battery 102 is first discharged. The auxiliary battery switch 420 initially connects the positive terminal auxiliary 413 to the power line 408 of the device, thereby feeding the device 100 via an auxiliary battery 102. The detector 422 monitors the electrochemical cell 412 while discharging. When a voltage of the auxiliary positive terminal 413 falls below the threshold voltage, the detector 422 closes the main battery switch 424. This connects the main positive terminal 405 to the supply line 408 of the device, thus feeding the device 100 by means of of the main battery 101.

While one battery is in use, supplying power, the other battery that is not in use can be replaced (disassembled and reassembled) without interrupting the operation of the device 100. While the auxiliary battery 102 is in use, the main battery 101 can be replaced. While the main battery 101 is in use, the auxiliary battery 102 can be replaced. the auxiliary battery 102, the detector 422 opens the main battery switch 424 (and disconnects the main battery 101) if the auxiliary positive terminal voltage 413 is above the threshold voltage.

Also, the battery in use can be disassembled without interrupting the operation of the device 100. If the auxiliary battery 102 is removed while in use, the detector in response to the rapidly descending voltage on line 421 closes the main battery switch 424 quickly enough to prevent interruption. The interruption is also prevented when the main battery 101 is dismantled while in use, even after the auxiliary battery 102 has already been discharged up to the threshold voltage. This is achieved by adjusting the threshold voltage (eg 3.3V) above a minimum voltage which is necessary to power the device 100. In the preferred embodiment, the minimum voltage is 2.8V. Also, the auxiliary battery switch 420 should be designed to remain closed even after the auxiliary battery 102 has been discharged to the threshold voltage. Therefore, after disassembling the main battery 101 while in use, the auxiliary battery 102 can still supply sufficient power to operate the device 100 (at least for a short time). Also, the detector opens the battery control switch 424 when the presence of the main positive terminal 405 is no longer detected at the second input thereof.

This dismantling of the battery in use is an advantageous feature for users who wish to replace the battery in use during a telephone call without interrupting the telephone call. In the preferred embodiment, the main battery 101 is smaller than the auxiliary battery 102 (see Figs. 1 and 2) and, therefore, more portable. It is then foreseen that users will carry more main batteries than auxiliary batteries. The ability to replace the main battery 101 while in use is therefore advantageous.

When an external power 430 (designated B + EXTERNAL) is mounted on the connector 314, the discharge of the main battery 101 or the auxiliary battery 102 is stopped and the device 100 is powered by the external power 430. The external power 430 supplies the device with a power line 408 with a voltage that is approximately 1.4V higher than the voltage supplied by the main or auxiliary batteries 101, 102. After dismantling, the diode 432, which is connected between the connector 314 and the power line 408 of the device, is tilted forward and connects the voltage supplied by the external power 430 to the supply line 408 of the device. (When the external power supply 430 is not mounted, the diode 432 prevents the main and auxiliary batteries 101, 102 from draining current to the connector 314.) In response to the highest voltage level in the power line 408 of the device, the power switch auxiliary battery 420 opens and unloads auxiliary battery stops 102. Detector 422, after sensing the presence of external power source 430 (via the third input) opens main battery switch 424 and discharges main battery stops 101 .

A load portion of the discharge and charge circuit 310 selectively charges the main and auxiliary batteries 101,102. The load portion of the discharge and charge circuit 310 includes a memory switch 440, a charge switch 442, an internal charger 444 and a thermistor switch 446. The charging portion of the charge and discharge circuit 310 operates under control of the 306 controller.

The controller 306 selectively reads the contents of the main and auxiliary memories 402,410 via the memory switch 440. The main memory 402 is connected to a first input of the memory switch 440 on the line 448. The auxiliary memory 410 is connected to a second memory. input of memory switch 440 on line 450. Controller 306 is connected to a third input of memory switch 440 on line 452. Memory switch 440 includes an output that is connected to controller 306 on line 454. controller 306 instructs memory switch 440 via line 452 to connect main memory 402 or auxiliary memory 410 to controller 306 via the output of memory switch 440 and line 454. Once the connection is established, controller 306 Read the battery data.

The controller selects the main battery 101 or the auxiliary battery 102 to charge it by the charge switch 442. The load switch 442 includes a first output which is connected to the electrochemical cell 404 by the line 456. The load switch 442 includes a second inlet which is connected to the electrochemical cell 412 by the line 458. The internal charger 444 is connected to the first input of the charge switch 442 by the line 460. The controller 306 is connected by the second input of the charge switch 442 by line 452. Controller 306 instructs charging switch 442 on line 452 to connect internal charger 444 through the first input of the charge switch and line 460 to the main electrochemical cell 404 or to the auxiliary electrochemical cell 412. Once concted, a charge current supplied by the internal charger 444 charges the main electrochemical cell 404 or the elect auxiliary rochetry 412.

The controller 306 determines the presence of the main and auxiliary batteries 101, 102 by the thermistor switch 446. The main thermistor 406 is connected to the thermistor switch 446 by the line 462. The auxiliary thermistor 414 is connected to a second input of the thermistor switch via line 464. Controller 306 is connected to a third output of thermistor switch 446 on line 465. Thermistor switch 446 includes an output that is connected to controller 306 via line 466. Controller 306 indicates the thermistor 446 via line 464 which coheses the main thermistor 406 or the auxiliary thermistor 414 to the controller 306 through the output of the thermistor switch and line 466. Once connected the controller 306 determines the presence of the main battery 101 or the auxiliary battery 102 due to the voltage drop in the respective thermistor.

The internal charger 444 includes a charge controller 470, a current regulator 472 and a feedback switch 474. The charge controller 470 is connected to the connector 314 via line 478, to controller 306 via line 480 and to the charging current on line 481. The charge controller 470 in response to the connector 314, the controller 306 and the charging current, emits a current signal to the current regulator 472. In addition to having inputs to receive the current from the charge controller 470 , the current regulator 472 includes an input which is connected to the connector 314 by the line 482. The current regulator 472, in response to the current, produces the charging current at a first or second speed of the load switch 422 by the line 460. After producing the charging current, the current regulator 472 closes the feedback switch 474 on the line 484. The feedback switch 4 74, once closed, connects the load voltage on line 460 to connector 314 on line 486. The load voltage is used for tracking by external power 430.

The load portion of the unload and charge circuit 3190 charges the main and auxiliary batteries 101,102 according to a predetermined priority - when both batteries are mounted, the main battery 101 is discharged first. Charging begins after mounting an external power source able to charge batteries, eg. external power 430, to connector 314. Controller 306, which picks up the external power supply 430 via line 488, switches between the main and auxiliary thermistors 406.414 via thermistor switch 446 to determine which battery is present. If the two main and auxiliary batteries 101,102 are mounted, the controller 306 switches the memory switch 440 and reads the data from the main memory 402 via the line 454. The external power 430 feeds the charge controller 470 along the line 478. The controller 306 configures charge controller 470 via line 480 such that charge controller 470 supplies a current signal in accordance with the data read from main battery 101. Feedback is provided on line 481 in such a way that the 470 charge controller can adjust the current signal, if necessary. The current controller 472, in response to the current signal of the charge controller 470, generates the load current using the external power 430 provided by the line 482. The current controller 470 emits load current to the load switch 442 on line 460. Controller 306 switches charge switch 442 to connect load current to main electrochemical cell 404 on line 456. The. Main battery 101 is charged for a period according to the data read in main memory 402. After charging during this period, main battery 101 is considered full.

Once the main battery 101 is fully charged, charging of the auxiliary battery 102 starts. The controller 306 switches the memory switch 440 and reads the data from the auxiliary memory 410. The controller 306 configures the interphone charger 444 to emit the charging current according to the data read in the auxiliary memory 102. The controller 306 switches the charging switch 442 to connect the charging current to the electromechanical cell 412 via the line 416. The auxiliary battery 102 is charged for a period of time. according to the optimal charging time data read in the auxiliary memory 410 and then it is considered full. If the main battery 101 is replaced while the main battery 102 is being charged, the controller 306 (which continuously manipulates the thermistor switch 446 between the main and auxiliary thermistors 406.414 to determine the presence of battery during charging) interrupts the charging of the battery. auxiliary battery 102 and begins to charge the main battery 101 in the manner mentioned. Once the two main and auxiliary batteries 101, 102 are full, the internal charger 444 repeatedly applies a maintenance charge to each of the main and auxiliary batteries 101, 102 for a period of about 1800 seconds. The maintenance charge comprises slow or finished charging to delay the depletion of the battery. Charging ends after mounting external power 430.

Although the device 100 includes an internal charger 444 for charging the multi-battery arrangement, it will be recognized that the charging means of the main and auxiliary batteries 101, 102 could be external to the device 100. For example, without the internal charger 444, the charge of the main and auxiliary batteries 101,102 could be made with an external charger mounted on the connector 314. In addition to being connected to the controller 306, the connector 314 would also be directly connected to the thermistor switch 446, the memory switch 440 and the charge switch 442 After mounting the external charger, the presence of the battery is determined with the thermistor switch 446, the battery data is read from the main memory 402 or the auxiliary memory 410 and the charging current based on the battery data is supplies the main battery 101 or the auxiliary battery 102 via the charge switch 442.

Fig. 5 is a partial schematic illustration of the discharge and charge circuit 310. As noted, the discharge of the main and auxiliary batteries 101,102 is performed with the auxiliary battery switch 420, the detector 422 and the main battery switch 424. The auxiliary battery switch 420 comprises the diode 500, which is preferably a Schottky rectifier. The input of the diode 500 is connected to the auxiliary positive terminal 413 by the line 416. The output of the diode 500 is connected to the power line 408 of the device.

The detector 422 mainly includes a comparator 502, transistor 504, diode 510 and a logic gate OR 506. The comparator 502 has a reference voltage 508 (designated VREF) set to the threshold voltage of the auxiliary battery 102 and connected to a positive terminal (+) of that one. The auxiliary positive terminal 413 is connected to a negative terminal (-) of the comparator 502 on the line 421. The output of the comparator 502 is connected to a first input of the logic gate OR 506. A logic gate of the transistor 504 is preferably a MOSFET of channel n, connected to the main positive terminal 405 by line 423. A drain of transistor 504 is connected to auxiliary battery terminal 413 and to a second input of logic gate OR 506. Diode 510 is connected between drain of transistor 504 and logic gate O 506. The second input of logic gate O 506 is also connected to connector 314. The output of logic gate O 506 is also connected to main battery switch 424 on line 426.

The main battery switch 424 includes the transistor 512, which is preferably a MOSFET of the spreading type of channel p, and the diode 514. A logic gate of the transistor 512 is connected to the output of the logic gate O 506 by the line 426 A drain of transistor 512 is connected to the main positive terminal on line 427. A source of transistor 512 is connected to power line 408 of the device. The diode 514 is connected between the source and the drain of the transistor.

When the main and auxiliary batteries 101,102 are mounted (and the external power 430 is not mounted), the diode is tilted forward and connects the auxiliary positive terminal to the supply line 408 of the device. If the voltage level of the auxiliary positive terminal 413 is greater than or approximately equal to the reference voltage 508, the comparator 502 outputs a logic high signal. This causes the logic gate O 506 to emit a logic high signal on the line 426. This, in turn, causes the transistor 512 to turn off, thus preventing the positive terminal 405 from feeding the power supply line 408 of the device. The diode 514 prevents the current from the supply line 408 of the device from draining backward and charging the main battery 101.

If the voltage level of the auxiliary positive terminal 413 falls below the reference voltage 508, the comparator 502 emits a logic low signal to the logic gate O 506. This causes the O 506 gate to emit a logic low signal in the line 426. If the two main and auxiliary batteries 101,102 are still present, the transistor 504 also emits a logic low signal to the logic gate O 506. This causes the logic gate O 506 to emit a logic low signal on the line 426. And, in turn, it causes the transistor 512 to turn on and connect the main positive terminal 405 to the power line 408 of the device.

If the main battery 101 is removed (and the auxiliary battery 102 is mounted), the logic gate of the transistor 504 no longer sees, i.e., it is not powered by the main positive terminal 405. This causes the drain of the transistor 504 to be pulled high by the auxiliary positive terminal 413. This, in turn, causes the logic gate O 506 to emit a logic high signal on line 426 and the transistor to remain off.

When the external power 430 is mounted on the connector 314, the main and auxiliary batteries 101,102 stop the discharge. Once mounted, the presence of the external power 430 on line 425 causes logic gate 0 to emit the logic high signal on line 426. This causes the transistor to turn off. The diode 510 prevents the external supply current 430 from draining backward and charging the main battery 101. The higher voltage supplied to the supply line 408 of the device by the external supply 430 prevents the forward inclination of the diode 500.

As has been said, for charging the main and auxiliary batteries 101,102 the discharge and charge circuit 310 includes the memory switch 440; the load switch 442; the charge controller 470; the current controller 472 and the feedback switch 474 of the internal charger 444; and the thermistor switch 446. The memory and thermistor switches 440.446 are preferably two multiplexers / demultiplexers that are driven by a power 520 of 2.75V. Each of the memory and thermistor switches 440.446 mainly includes first and second channel gates 552.524 connected to lines 448, 464 and lines 450.462, respectively; a communication gate 526 connected to lines 454,466; and a selection gate 528 connected to lines 452.465. A logic low signal connected to the selection gate 528 from the controller 306 connects the first channel gate 522 (connected to the main battery 101) with the communication gate 526 and then with the controller 306. A high logic signal connected to the selection gate 528 from the controller 306 connects the second channel gate 524 (connected to the auxiliary battery 101) to the communication gate 526 and then to the controller 306.

The load switch 442 includes transistors 530,532,534,536. The transistors 530,532,534,536 are preferably MOSFETs of the p-channel spreading mode. The logic gates of the transistors 530,532 are connected to the line 452. The logic gates of the transistors 534,536 are connected to the line 452 by an inverter logic gate 538. The sources of the transistors 530,534 are connected to the line 460. The sources of the transistors 532,536 are connected to the main and auxiliary positive terminals 405,413 by the lines 456,458, respectively. The drains of the transistors 530,532 are connected. The drains of transistors 534,536 are joined. The diodes 540,542,544,546 are connected to the transistors 530,532,534,536, respectively, from the drain to the source. A logic low signal on line 452 switches on transistors 534,536 so that the current load on line 460 can flow to main battery 101. A high logic signal on line 452 switches on transistors 530,532 in such a way that the current load on line 460 can flow towards auxiliary battery 102. Diodes 540,542,544,546 prevent the current load from flowing to the battery not selected for charging.

The charge controller 470, which is preferably an integrated circuit, mainly comprises a controlled current source 550, for example a pulse duration modulator (PM), which generates an output current signal at a level determined by the controller. load 470. Current source 550 is supplied by connector 314 via line 478 in the first input gate, configured by controller 306 via line 480 in the second input gate and set with line 481 in the third gate of entry. The charge controller 470 connects a current signal generated by the current source 550, in response to the controller 306 and the settings based on the feedback received by 481, to the current controller 472 via an output gate 551 and a sensor gate 552 .

The current controller 472 mainly includes a transistor 553, diode 554 and diode 556. The transistor 553 is preferably a MOSFET of the p-channel spreading mode. A logic gate of the transistor 553 is connected to the output gate 551 of the cage controller 470. A source of the transistor 553 is connected to the sensor gate 552 of the charge controller 470 and the connector 314 (and the external power 430) by the line 482. A drain of transistor 553 is output to feedback switch 474 via line 484 and goes to line 460 via diode 556. Transistor 552, in response to the load signal received from output gate 551 of the charge controller 470, turn on and turn on the current generated by the external power 430 and the current source 550 (the charge signal supplied through the sensor gate 552 of the charge controller 470) to the line 460 through the diode 556 The diode 556 is preferably a Schottky rectifier. The diode 554 is connected to the transistor 553 from the drain to the source and prevents the charging current from flowing to the line 460 when the transistor 553 is turned off.

The feedback switch 474 mainly includes transistors 560,562. The transistors 560,562 are preferably bipolar junction transistors. The transistor 560 is an npn transistor. A base of the transistor 560 is connected to the current regulator 472 via the line 484. A collector of the transistor 560 is connected to a base of the transistor 562. The transistor 560 is turned on in response to the charge current generated by the regulator of the transistor. current 472. Transistor 562 is a pnp transistor. An emitter of transistor 562 is connected to line 460. A collector of transistor 562 is connected to connector 314 via line 486. Transistor 562 connects the charge voltage output by means of current regulator 472 to connector 314 when the transistor 560 is on. This allows the external power 430 to track the charging voltage.

Fig. 6 is a flowchart illustration of a main and auxiliary discharge method 101,102 of Figs. 1-5. In the preferred embodiment, this method or process is implemented exclusively by the auxiliary battery switch 420, the detector 422 and the main battery switch 424 of the discharge and charge circuit 310 of Figs. 4 and 5. It will be recognized, however , that this method can also be implemented by a software program executed by the microprocessor or controller.

The process is started in block 600. In decision block 602, it is determined whether the external power 430 of Figs. 4 and 5 is mounted to device 100 of Figs. 1-3, or not. If the external power 430 is mounted, the device 100 is driven by the external power 430 in the block 604 and the process returns to the decision block 602. If the external power 430 is not mounted, the process passes to the decision block 606 .

In the decision block 606, it is determined whether the auxiliary battery 102 of Figs. 1-5 is mounted or not in the device 100. If the auxiliary battery 102 is not mounted, the process passes to the decision block 608. If the The auxiliary battery 102 is mounted, it is deterninated if the voltage of the auxiliary battery 102 is or not greater than the reference voltage 508 of Fig.5 in the decision block 610. If the voltage of the auxiliary battery 102 is higher, the device 100 is driven by auxiliary battery 102 in block 612 and the process returns to decision block 602. If the voltage of auxiliary battery 102 is not higher, the process passes to decision block 608.

In decision block 608, it is determined whether main battery 101 of Figs. 1-5 is mounted, or not. if the main battery 101 is mounted, the device 100 is driven by the main battery 101 in the block 614 and then the process returns to the decision block 602. If the main battery 101 is not mounted, the process stops in block 615 since there are no feeder sources mounted on the device 100.

Fig.7 is an illustration in diagram form of a state of a method for charging the main and auxiliary batteries 101, 102 of Figs. 1-5. In the preferred embodiment, this method or process is implemented using a software program executed by controller 306 of Figs. 3-5. According to the program, the controller 306 operates the memory switch 440, the charge switch 442, the internal charger 444 and the thermistor switch 446 of the discharge and charge circuit 310 of FIGS. 4 and 5 for charging the main and auxiliary batteries 101 and 102. It will be recognized, however, that this method can be implemented using only discrete hardware components. Each state is represented by a block. The number in the upper left corner of each block indicates the number of batteries mounted in device 100 of Figs. 1-3 during that state.

Block 700 indicates a state in which there is no battery mounted. If the main battery 101 is mounted in the device 100 in the block 700, the process advances to the block 702. If the auxiliary battery 102 is mounted in the block 700, the process advances to the block 704.

Block 702 indicates a state in which only main battery 101 is mounted and is being charged. If the main battery 101 is removed in block 702, the process advances to block 700. If auxiliary battery 102 is mounted in block 702, the process advances to block 706. If main battery 101 is fully charged in block 702 , the process advances to block 708.

Block 704 indicates a state in which only the auxiliary battery 102 is mounted and is being charged. If auxiliary battery 102 is removed in block 702, the process advances to block 700. If main battery 101 is mounted in block 704, the process advances to block 706. If auxiliary battery 102 is fully charged in block 706 , the process advances to block 710.

The block 706 indicates a state in which the two main and auxiliary batteries 101, 102 are mounted and the main battery 101 is charging. If the main battery 101 is removed in the block 706, the process advances to the block 704. If the auxiliary battery 102 is removed in the block 706, the process advances to the block 702. If the main battery 101 is fully charged in the block 706 , the process advances to block 712.

The block 708 initiates a state in which only the main battery 101 is mounted and in maintenance charge. If the main battery 101 is removed in the block 708, the process advances to the block 700. If the auxiliary battery 102 is mounted in the block 708, the process advances to block 712. Block 710 indicates a state in which only the battery Auxiliary 102 is mounted and under maintenance load. If auxiliary battery 102 is removed in block 710, the process passes to block 700. If main battery 101 is mounted in block 710, the process goes to block 714.

Block 712 indicates a state in which the two main and auxiliary batteries 101,102 are mounted and the auxiliary battery 102 is charging. If the main battery 101 is removed in block 712, the process goes to block 704. If auxiliary battery 102 is removed in block 712, the process advances to block 708. If auxiliary battery 102 is fully charged in block 712 , the process advances to block 716.

Block 714 indicates a state in which the two main and auxiliary batteries 101,102 are mounted, main battery 101 is charging and auxiliary battery 102 is fully charged. If the main battery 101 is removed in block 714, the process advances to block 710. If auxiliary battery 102 is removed in block 714, the process advances to block 702. If main battery 101 is fully charged in block 714 , the process advances to block 716.

Block 716 indicates a state in which the two main and auxiliary 101,102 batteries are assembled and in maintenance charge. If the main battery 101 is removed in block 716, the process proceeds to block 710. If auxiliary battery 102 is removed in block 716, the process passes to block 708.

Fig. 8 is a diagrammatic illustration of a method for determining which of the main or auxiliary batteries 101,102 of Figs. 1-5 should be charged. This method is similar to that of Fig.7 because it is implemented using a software program executed by the controller 306 of Figs.4 and 5. According to this program, the controller 306 operates the memory switch 440, the load 442, the internal charger 444 and the thermistor switch 446 of the discharge and charge circuit 310 of FIGS. 4 and 5 to charge the main and auxiliary batteries 101 and 102. This method, however, can be implemented using discrete hardware components. Each state is represented by a block.

The block 800 indicates a state in which neither the main battery 101 nor the auxiliary battery 102 are charging. If the main battery 101 is' mounted in block 800, the process advances to block 802. If the auxiliary battery 102 is mounted in block 800, the process goes to 804.

Block 802 indicates a state in which only main battery 101 is charging. If the main and auxiliary batteries 101,102 are removed in block 802, the process passes to block 800. If auxiliary battery 102 is mounted, main battery 101 is fully charged and auxiliary battery 102 is not fully charged in block 802, the process advances to block 804. If auxiliary battery 102 is mounted and main battery 101 is removed in block 802, the process also passes to block 804.

Block 804 indicates a state in which only auxiliary battery 102 is being charged. If the main and auxiliary batteries 101,102 are removed in the block 804, the process advances to the block 800. If the main battery 101 is mounted and is not fully charged in the block 804, the process goes to block 802.

In summary, a portable electronic device is disclosed which has removable main and auxiliary batteries and a discharge and charge circuit to discharge and charge the batteries. The discharge and charge circuit discharges the batteries according to a predetermined priority - when both batteries are mounted, the auxiliary battery is always discharged first. The predetermined priority minimizes the complexity of the circuits that are required to discharge multiple batteries since only one voltage detector is needed to monitor the auxiliary battery voltage. When the auxiliary battery is discharged to a predetermined level, the detector switches a main battery switch that connects the main battery to power the device. Unlike the known art, the predetermined level is set above the minimum voltage necessary to power the device so that the auxiliary battery can power the device, without interruption, if the main battery should be replaced while in use. The discharge and charge circuit also charges the batteries according to a predetermined priority - when both batteries are mounted, the main battery always charges first. Charging is performed by a series of switches and an internal charger connected between the main and auxiliary batteries and a controller. Charging is initiated by mounting an external power supply to the device. The controller, run by a program executed by him, first selects the main battery to be charged and connects the charge current generated by the internal charger to the main battery. After fully charging the main battery, the controller switches to charge the auxiliary battery, if the main battery is replaced while the auxiliary battery is being charged, the controller switches to charge the main replacement battery.

Claims

1. An electronic device (100) including an apparatus (310) for discharging a battery arrangement for feeding the electronic device (100) in an operating state, the battery arrangement includes a main battery (101) and an auxiliary battery (102). ), the apparatus characterized by: a detector (422) connected to the main and auxiliary batteries for monitoring a voltage level of the auxiliary battery; and a main switch (424) connected to the main battery and the detector, the main switch operable to connect the main battery to power the electronic device without interruption in the operating state when the voltage level of the auxiliary battery is below a predetermined level and for disconnecting the main battery from the power of the device without interruption in the operating state when the voltage level of the auxiliary battery is above the predetermined level.

2. An electronic device according to claim 1 characterized by: an auxiliary switch (420) connected to the axular battery and operable to connect the auxiliary battery to power the electronic device regardless of the voltage level of the auxiliary battery.

3. An electronic device according to claim 2 further characterized by a connector (314) for releasably connecting an external power source (430) to provide external power to operate the electronic device in the operating state; and characterized in that the auxiliary switch, in response to the mounting of the external power supply, prevents the auxiliary battery from feeding the electronic device.

4. An electronic device according to claim 1 characterized in that the main and auxiliary batteries are removable.

5. An electronic device according to claim 1 characterized in that the main battery includes a first capacity and the auxiliary battery includes a second capacity, the second capacity is greater than the first capacity.

6. An electronic device (100) having a state of operation requiring a minimum voltage level, the electronic device characterized by: a first removable battery (102) mounted on the electronic device for feeding the electronic device in the operating state; a detector (422) for detecting the voltage level of the first removable battery; a switch (424) connected to the detector; and a second removable battery (101) mounted on the electronic device and connected to the switch, the switch, in response to the detector, for connecting the second removable battery to power the electronic device without interruption in the operating state when the first removable battery is Discharge at a predetermined voltage level, the predetermined voltage level is higher than the minimum voltage level to allow powering by the first removable battery of the electronic device without interruption in the operating state when the second removable battery is dismantled.

7. An electronic device (100) having an operating state, the electronic device characterized by: a first removable battery (102) mounted on the electronic device for feeding the electronic device in the operating state; a second removable battery (101) mounted on the electronic device for alternately feeding the electronic device in the operating state; a detector (422) for detecting a voltage level of the first removable battery; and a switch (424) connected to the second removable battery, the detector, and the electronic device, the switch connects the second removable battery to power the electronic device without interruption in the operating state when the first removable battery is removed.

8. An electronic device (100) including an apparatus (310) for charging a battery arrangement that feeds the electronic device, the battery arrangement includes a first battery (102) and a second battery (101), the apparatus characterized by: detectors (306,446) for detecting the presence of the first and second batteries; current generation circuits (444), in response to the detector circuits, to generate a load current; and switching circuits (442) connected to the first battery, the second battery and the current generating circuits, the switching circuits, when both the first battery and the second battery are present, it first connects the charging current to the second one. battery to charge the second battery, and then connect the charging current to charge the first battery, the switching circuits, after replacing the second battery during the charging of the first battery, immediately reconnect the charging current to charge the second battery.

9. A method for downloading a battery arrangement for powering a device (100) in an operating state, the method characterized by the following steps: detecting (610) a voltage level of a first battery (102) of the battery arrangement; connecting (612) the first battery to power the device as long as the voltage level exceeds a predetermined voltage level; and connecting (614), without interrupting the operating state, a second battery (101) of the battery arrangement to power the device when the voltage level is less than or equal to the predetermined voltage level.

10. A method for charging a battery arrangement by means of a charger (444) located inside a device (100), the arrangement of batteries to power the device to operate in a state of operation, the method characterized by the following steps: determining the presence of a first battery (101) and a second battery (102) of the battery arrangement; fully charge (802), while present, the first battery; fully charge (804), while present, the second battery; and interrupting the charging of the second battery after the replacement of the first battery and fully charging, while present, the first battery.